Unify naming of type lookups in c_type_map dict

[ldk-java] / genbindings.py

diff --git a/genbindings.py b/genbindings.py
index 87ada732e6ddc0fd66dcc69ca4a5f525f1620f6e..f47cce3699d823ab2f972ba47e161f2d69791fef 100755 (executable)
--- a/genbindings.py
+++ b/genbindings.py
@@ -1,202 +1,41 @@
 #!/usr/bin/env python3
 import sys, re
 
 #!/usr/bin/env python3
 import sys, re
 

-if len(sys.argv) != 6:
-    print("USAGE: /path/to/lightning.h /path/to/bindings/output.java /path/to/bindings/ /path/to/bindings/output.c debug")
+if len(sys.argv) < 7:
+    print("USAGE: /path/to/lightning.h /path/to/bindings/output /path/to/bindings/ /path/to/bindings/output.c debug lang")
+    sys.exit(1)
+
+if sys.argv[5] == "false":
+    DEBUG = False
+elif sys.argv[5] == "true":
+    DEBUG = True
+else:

     print("debug should be true or false and indicates whether to track allocations and ensure we don't leak")
     sys.exit(1)
 
     print("debug should be true or false and indicates whether to track allocations and ensure we don't leak")
     sys.exit(1)
 

-hu_struct_file_prefix = """package org.ldk.structs;
+target = None
+if sys.argv[6] == "java":
+    from java_strings import Consts
+elif sys.argv[6] == "typescript":
+    import typescript_strings
+    from typescript_strings import Consts
+    target = typescript_strings.Target.NODEJS
+    if len(sys.argv) == 8 and sys.argv[7] == 'browser':
+        target = typescript_strings.Target.BROWSER
+else:
+    print("Only java or typescript can be set for lang")
+    sys.exit(1)

 
 

-import org.ldk.impl.bindings;
-import org.ldk.enums.*;
-import org.ldk.util.*;
-import java.util.Arrays;

 
 

-@SuppressWarnings("unchecked") // We correctly assign various generic arrays
-"""
+consts = Consts(DEBUG, target=target)

 
 

-c_file_pfx = """#include \"org_ldk_impl_bindings.h\"
-#include <rust_types.h>
-#include <lightning.h>
-#include <string.h>
-#include <stdatomic.h>
-"""
-
-if sys.argv[5] == "false":
-    c_file_pfx = c_file_pfx + """#define MALLOC(a, _) malloc(a)
-#define FREE(p) if ((long)(p) > 1024) { free(p); }
-#define DO_ASSERT(a) (void)(a)
-#define CHECK(a)
-"""
-else:
-    c_file_pfx = c_file_pfx + """#include <assert.h>
-// Always run a, then assert it is true:
-#define DO_ASSERT(a) do { bool _assert_val = (a); assert(_assert_val); } while(0)
-// Assert a is true or do nothing
-#define CHECK(a) DO_ASSERT(a)
-
-// Running a leak check across all the allocations and frees of the JDK is a mess,
-// so instead we implement our own naive leak checker here, relying on the -wrap
-// linker option to wrap malloc/calloc/realloc/free, tracking everyhing allocated
-// and free'd in Rust or C across the generated bindings shared library.
-#include <threads.h>
-#include <execinfo.h>
-#include <unistd.h>
-static mtx_t allocation_mtx;
-
-void __attribute__((constructor)) init_mtx() {
-       DO_ASSERT(mtx_init(&allocation_mtx, mtx_plain) == thrd_success);
-}
-
-#define BT_MAX 128
-typedef struct allocation {
-       struct allocation* next;
-       void* ptr;
-       const char* struct_name;
-       void* bt[BT_MAX];
-       int bt_len;
-} allocation;
-static allocation* allocation_ll = NULL;
-
-void* __real_malloc(size_t len);
-void* __real_calloc(size_t nmemb, size_t len);
-static void new_allocation(void* res, const char* struct_name) {
-       allocation* new_alloc = __real_malloc(sizeof(allocation));
-       new_alloc->ptr = res;
-       new_alloc->struct_name = struct_name;
-       new_alloc->bt_len = backtrace(new_alloc->bt, BT_MAX);
-       DO_ASSERT(mtx_lock(&allocation_mtx) == thrd_success);
-       new_alloc->next = allocation_ll;
-       allocation_ll = new_alloc;
-       DO_ASSERT(mtx_unlock(&allocation_mtx) == thrd_success);
-}
-static void* MALLOC(size_t len, const char* struct_name) {
-       void* res = __real_malloc(len);
-       new_allocation(res, struct_name);
-       return res;
-}
-void __real_free(void* ptr);
-static void alloc_freed(void* ptr) {
-       allocation* p = NULL;
-       DO_ASSERT(mtx_lock(&allocation_mtx) == thrd_success);
-       allocation* it = allocation_ll;
-       while (it->ptr != ptr) {
-               p = it; it = it->next;
-               if (it == NULL) {
-                       fprintf(stderr, "Tried to free unknown pointer %p at:\\n", ptr);
-                       void* bt[BT_MAX];
-                       int bt_len = backtrace(bt, BT_MAX);
-                       backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
-                       fprintf(stderr, "\\n\\n");
-                       DO_ASSERT(mtx_unlock(&allocation_mtx) == thrd_success);
-                       return; // addrsan should catch malloc-unknown and print more info than we have
-               }
-       }
-       if (p) { p->next = it->next; } else { allocation_ll = it->next; }
-       DO_ASSERT(mtx_unlock(&allocation_mtx) == thrd_success);
-       DO_ASSERT(it->ptr == ptr);
-       __real_free(it);
-}
-static void FREE(void* ptr) {
-       if ((long)ptr < 1024) return; // Rust loves to create pointers to the NULL page for dummys
-       alloc_freed(ptr);
-       __real_free(ptr);
-}
-
-void* __wrap_malloc(size_t len) {
-       void* res = __real_malloc(len);
-       new_allocation(res, "malloc call");
-       return res;
-}
-void* __wrap_calloc(size_t nmemb, size_t len) {
-       void* res = __real_calloc(nmemb, len);
-       new_allocation(res, "calloc call");
-       return res;
-}
-void __wrap_free(void* ptr) {
-       if (ptr == NULL) return;
-       alloc_freed(ptr);
-       __real_free(ptr);
-}
-
-void* __real_realloc(void* ptr, size_t newlen);
-void* __wrap_realloc(void* ptr, size_t len) {
-       if (ptr != NULL) alloc_freed(ptr);
-       void* res = __real_realloc(ptr, len);
-       new_allocation(res, "realloc call");
-       return res;
-}
-void __wrap_reallocarray(void* ptr, size_t new_sz) {
-       // Rust doesn't seem to use reallocarray currently
-       assert(false);
-}
-
-void __attribute__((destructor)) check_leaks() {
-       for (allocation* a = allocation_ll; a != NULL; a = a->next) {
-               fprintf(stderr, "%s %p remains:\\n", a->struct_name, a->ptr);
-               backtrace_symbols_fd(a->bt, a->bt_len, STDERR_FILENO);
-               fprintf(stderr, "\\n\\n");
-       }
-       DO_ASSERT(allocation_ll == NULL);
-}
-"""
+from bindingstypes import *

 
 c_file = ""
 def write_c(s):
     global c_file
     c_file += s
 
 
 c_file = ""
 def write_c(s):
     global c_file
     c_file += s
 

-class TypeInfo:
-    def __init__(self, is_native_primitive, rust_obj, java_ty, java_fn_ty_arg, java_hu_ty, c_ty, passed_as_ptr, is_ptr, var_name, arr_len, arr_access, subty=None):
-        self.is_native_primitive = is_native_primitive
-        self.rust_obj = rust_obj
-        self.java_ty = java_ty
-        self.java_hu_ty = java_hu_ty
-        self.java_fn_ty_arg = java_fn_ty_arg
-        self.c_ty = c_ty
-        self.passed_as_ptr = passed_as_ptr
-        self.is_ptr = is_ptr
-        self.var_name = var_name
-        self.arr_len = arr_len
-        self.arr_access = arr_access
-        self.subty = subty
-        self.pass_by_ref = is_ptr
-        self.requires_clone = None
-
-class ConvInfo:
-    def __init__(self, ty_info, arg_name, arg_conv, arg_conv_name, arg_conv_cleanup, ret_conv, ret_conv_name, to_hu_conv, to_hu_conv_name, from_hu_conv):
-        assert(ty_info.c_ty is not None)
-        assert(ty_info.java_ty is not None)
-        assert(arg_name is not None)
-        self.passed_as_ptr = ty_info.passed_as_ptr
-        self.rust_obj = ty_info.rust_obj
-        self.c_ty = ty_info.c_ty
-        self.java_ty = ty_info.java_ty
-        self.java_hu_ty = ty_info.java_hu_ty
-        self.java_fn_ty_arg = ty_info.java_fn_ty_arg
-        self.arg_name = arg_name
-        self.arg_conv = arg_conv
-        self.arg_conv_name = arg_conv_name
-        self.arg_conv_cleanup = arg_conv_cleanup
-        self.ret_conv = ret_conv
-        self.ret_conv_name = ret_conv_name
-        self.to_hu_conv = to_hu_conv
-        self.to_hu_conv_name = to_hu_conv_name
-        self.from_hu_conv = from_hu_conv
-
-    def print_ty(self):
-        write_c(self.c_ty)
-        out_java.write(self.java_ty)
-
-    def print_name(self):
-        if self.arg_name != "":
-            out_java.write(" " + self.arg_name)
-            write_c(" " + self.arg_name)
-        else:
-            out_java.write(" arg")
-            write_c(" arg")
-

 def camel_to_snake(s):
     # Convert camel case to snake case, in a way that appears to match cbindgen
     con = "_"
 def camel_to_snake(s):
     # Convert camel case to snake case, in a way that appears to match cbindgen
     con = "_"


@@ -329,15 +168,17 @@ def java_c_types(fn_arg, ret_arr_len):
             res.pass_by_ref = True
         if res.is_native_primitive or res.passed_as_ptr:
             return TypeInfo(rust_obj=fn_arg.split(" ")[0], java_ty=res.java_ty + "[]", java_hu_ty=res.java_hu_ty + "[]",
             res.pass_by_ref = True
         if res.is_native_primitive or res.passed_as_ptr:
             return TypeInfo(rust_obj=fn_arg.split(" ")[0], java_ty=res.java_ty + "[]", java_hu_ty=res.java_hu_ty + "[]",

-                java_fn_ty_arg="[" + res.java_fn_ty_arg, c_ty=res.c_ty + "Array", passed_as_ptr=False, is_ptr=is_ptr,
+                java_fn_ty_arg="[" + res.java_fn_ty_arg, c_ty=res.c_ty + "Array", passed_as_ptr=False, is_ptr=is_ptr, is_const=is_const,

                 var_name=res.var_name, arr_len="datalen", arr_access="data", subty=res, is_native_primitive=False)
         else:
             return TypeInfo(rust_obj=fn_arg.split(" ")[0], java_ty=res.java_ty + "[]", java_hu_ty=res.java_hu_ty + "[]",
                 var_name=res.var_name, arr_len="datalen", arr_access="data", subty=res, is_native_primitive=False)
         else:
             return TypeInfo(rust_obj=fn_arg.split(" ")[0], java_ty=res.java_ty + "[]", java_hu_ty=res.java_hu_ty + "[]",

-                java_fn_ty_arg="[" + res.java_fn_ty_arg, c_ty="jobjectArray", passed_as_ptr=False, is_ptr=is_ptr,
+                java_fn_ty_arg="[" + res.java_fn_ty_arg, c_ty=consts.ptr_arr, passed_as_ptr=False, is_ptr=is_ptr, is_const=is_const,

                 var_name=res.var_name, arr_len="datalen", arr_access="data", subty=res, is_native_primitive=False)
 
     is_primitive = False
     arr_len = None
                 var_name=res.var_name, arr_len="datalen", arr_access="data", subty=res, is_native_primitive=False)
 
     is_primitive = False
     arr_len = None

+    mapped_type = []
+    java_type_plural = None

     if fn_arg.startswith("void"):
         java_ty = "void"
         c_ty = "void"
     if fn_arg.startswith("void"):
         java_ty = "void"
         c_ty = "void"


@@ -351,26 +192,31 @@ def java_c_types(fn_arg, ret_arr_len):
         fn_arg = fn_arg[4:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint8_t"):
         fn_arg = fn_arg[4:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint8_t"):

-        java_ty = "byte"
-        c_ty = "jbyte"
+        mapped_type = consts.c_type_map['uint8_t']
+        java_ty = mapped_type[0]
+        c_ty = "int8_t"

         fn_ty_arg = "B"
         fn_arg = fn_arg[7:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint16_t"):
         fn_ty_arg = "B"
         fn_arg = fn_arg[7:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint16_t"):

-        java_ty = "short"
-        c_ty = "jshort"
+        mapped_type = consts.c_type_map['uint16_t']
+        java_ty = mapped_type[0]
+        c_ty = "int16_t"

         fn_ty_arg = "S"
         fn_arg = fn_arg[8:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint32_t"):
         fn_ty_arg = "S"
         fn_arg = fn_arg[8:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint32_t"):

-        java_ty = "int"
-        c_ty = "jint"
+        mapped_type = consts.c_type_map['uint32_t']
+        java_ty = mapped_type[0]
+        c_ty = "int32_t"

         fn_ty_arg = "I"
         fn_arg = fn_arg[8:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint64_t") or fn_arg.startswith("uintptr_t"):
         fn_ty_arg = "I"
         fn_arg = fn_arg[8:].strip()
         is_primitive = True
     elif fn_arg.startswith("uint64_t") or fn_arg.startswith("uintptr_t"):

-        java_ty = "long"
-        c_ty = "jlong"
+        # TODO: uintptr_t is arch-dependent :(
+        mapped_type = consts.c_type_map['uint64_t']
+        java_ty = mapped_type[0]
+        c_ty = "int64_t"

         fn_ty_arg = "J"
         if fn_arg.startswith("uint64_t"):
             fn_arg = fn_arg[8:].strip()
         fn_ty_arg = "J"
         if fn_arg.startswith("uint64_t"):
             fn_arg = fn_arg[8:].strip()


@@ -393,13 +239,13 @@ def java_c_types(fn_arg, ret_arr_len):
         ma = var_ty_regex.match(fn_arg)
         if ma.group(1).strip() in unitary_enums:
             java_ty = ma.group(1).strip()
         ma = var_ty_regex.match(fn_arg)
         if ma.group(1).strip() in unitary_enums:
             java_ty = ma.group(1).strip()

-            c_ty = "jclass"
+            c_ty = consts.result_c_ty

             fn_ty_arg = "Lorg/ldk/enums/" + ma.group(1).strip() + ";"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()
             fn_ty_arg = "Lorg/ldk/enums/" + ma.group(1).strip() + ";"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()

-            take_by_ptr = True

         elif ma.group(1).strip().startswith("LDKC2Tuple"):
         elif ma.group(1).strip().startswith("LDKC2Tuple"):

-            java_ty = "long"
+            c_ty = consts.ptr_c_ty
+            java_ty = consts.ptr_native_ty

             java_hu_ty = "TwoTuple<"
             if not ma.group(1).strip() in tuple_types:
                 assert java_c_types_none_allowed
             java_hu_ty = "TwoTuple<"
             if not ma.group(1).strip() in tuple_types:
                 assert java_c_types_none_allowed


@@ -415,13 +261,13 @@ def java_c_types(fn_arg, ret_arr_len):
                 else:
                     java_hu_ty = java_hu_ty + ty_info.java_hu_ty
             java_hu_ty = java_hu_ty + ">"
                 else:
                     java_hu_ty = java_hu_ty + ty_info.java_hu_ty
             java_hu_ty = java_hu_ty + ">"

-            c_ty = "jlong"

             fn_ty_arg = "J"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()
             take_by_ptr = True
         elif ma.group(1).strip().startswith("LDKC3Tuple"):
             fn_ty_arg = "J"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()
             take_by_ptr = True
         elif ma.group(1).strip().startswith("LDKC3Tuple"):

-            java_ty = "long"
+            c_ty = consts.ptr_c_ty
+            java_ty = consts.ptr_native_ty

             java_hu_ty = "ThreeTuple<"
             if not ma.group(1).strip() in tuple_types:
                 assert java_c_types_none_allowed
             java_hu_ty = "ThreeTuple<"
             if not ma.group(1).strip() in tuple_types:
                 assert java_c_types_none_allowed


@@ -437,15 +283,14 @@ def java_c_types(fn_arg, ret_arr_len):
                 else:
                     java_hu_ty = java_hu_ty + ty_info.java_hu_ty
             java_hu_ty = java_hu_ty + ">"
                 else:
                     java_hu_ty = java_hu_ty + ty_info.java_hu_ty
             java_hu_ty = java_hu_ty + ">"

-            c_ty = "jlong"

             fn_ty_arg = "J"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()
             take_by_ptr = True
         else:
             fn_ty_arg = "J"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()
             take_by_ptr = True
         else:

-            java_ty = "long"
+            c_ty = consts.ptr_c_ty
+            java_ty = consts.ptr_native_ty

             java_hu_ty = ma.group(1).strip().replace("LDKCResult", "Result").replace("LDK", "")
             java_hu_ty = ma.group(1).strip().replace("LDKCResult", "Result").replace("LDK", "")

-            c_ty = "jlong"

             fn_ty_arg = "J"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()
             fn_ty_arg = "J"
             fn_arg = ma.group(2).strip()
             rust_obj = ma.group(1).strip()


@@ -454,8 +299,8 @@ def java_c_types(fn_arg, ret_arr_len):
     if fn_arg.startswith(" *") or fn_arg.startswith("*"):
         fn_arg = fn_arg.replace("*", "").strip()
         is_ptr = True
     if fn_arg.startswith(" *") or fn_arg.startswith("*"):
         fn_arg = fn_arg.replace("*", "").strip()
         is_ptr = True

-        c_ty = "jlong"
-        java_ty = "long"
+        c_ty = consts.ptr_c_ty
+        java_ty = consts.ptr_native_ty

         fn_ty_arg = "J"
         is_primitive = False
 
         fn_ty_arg = "J"
         is_primitive = False
 


@@ -463,19 +308,23 @@ def java_c_types(fn_arg, ret_arr_len):
     if var_is_arr is not None or ret_arr_len is not None:
         assert(not take_by_ptr)
         assert(not is_ptr)
     if var_is_arr is not None or ret_arr_len is not None:
         assert(not take_by_ptr)
         assert(not is_ptr)

-        java_ty = java_ty + "[]"
+        # is there a special case for plurals?
+        if len(mapped_type) == 2:
+            java_ty = mapped_type[1]
+        else:
+            java_ty = java_ty + "[]"

         c_ty = c_ty + "Array"
         if var_is_arr is not None:
             if var_is_arr.group(1) == "":
         c_ty = c_ty + "Array"
         if var_is_arr is not None:
             if var_is_arr.group(1) == "":

-                return TypeInfo(rust_obj=rust_obj, java_ty=java_ty, java_hu_ty=java_ty, java_fn_ty_arg="[" + fn_ty_arg, c_ty=c_ty,
+                return TypeInfo(rust_obj=rust_obj, java_ty=java_ty, java_hu_ty=java_ty, java_fn_ty_arg="[" + fn_ty_arg, c_ty=c_ty, is_const=is_const,

                     passed_as_ptr=False, is_ptr=False, var_name="arg", arr_len=var_is_arr.group(2), arr_access=arr_access, is_native_primitive=False)
                     passed_as_ptr=False, is_ptr=False, var_name="arg", arr_len=var_is_arr.group(2), arr_access=arr_access, is_native_primitive=False)

-            return TypeInfo(rust_obj=rust_obj, java_ty=java_ty, java_hu_ty=java_ty, java_fn_ty_arg="[" + fn_ty_arg, c_ty=c_ty,
+            return TypeInfo(rust_obj=rust_obj, java_ty=java_ty, java_hu_ty=java_ty, java_fn_ty_arg="[" + fn_ty_arg, c_ty=c_ty, is_const=is_const,

                 passed_as_ptr=False, is_ptr=False, var_name=var_is_arr.group(1), arr_len=var_is_arr.group(2), arr_access=arr_access, is_native_primitive=False)
 
     if java_hu_ty is None:
         java_hu_ty = java_ty
     return TypeInfo(rust_obj=rust_obj, java_ty=java_ty, java_hu_ty=java_hu_ty, java_fn_ty_arg=fn_ty_arg, c_ty=c_ty, passed_as_ptr=is_ptr or take_by_ptr,
                 passed_as_ptr=False, is_ptr=False, var_name=var_is_arr.group(1), arr_len=var_is_arr.group(2), arr_access=arr_access, is_native_primitive=False)
 
     if java_hu_ty is None:
         java_hu_ty = java_ty
     return TypeInfo(rust_obj=rust_obj, java_ty=java_ty, java_hu_ty=java_hu_ty, java_fn_ty_arg=fn_ty_arg, c_ty=c_ty, passed_as_ptr=is_ptr or take_by_ptr,

-        is_ptr=is_ptr, var_name=fn_arg, arr_len=arr_len, arr_access=arr_access, is_native_primitive=is_primitive)
+        is_const=is_const, is_ptr=is_ptr, var_name=fn_arg, arr_len=arr_len, arr_access=arr_access, is_native_primitive=is_primitive)

 
 fn_ptr_regex = re.compile("^extern const ([A-Za-z_0-9\* ]*) \(\*(.*)\)\((.*)\);$")
 fn_ret_arr_regex = re.compile("(.*) \(\*(.*)\((.*)\)\)\[([0-9]*)\];$")
 
 fn_ptr_regex = re.compile("^extern const ([A-Za-z_0-9\* ]*) \(\*(.*)\)\((.*)\);$")
 fn_ret_arr_regex = re.compile("(.*) \(\*(.*)\((.*)\)\)\[([0-9]*)\];$")


@@ -483,6 +332,13 @@ reg_fn_regex = re.compile("([A-Za-z_0-9\* ]* \*?)([a-zA-Z_0-9]*)\((.*)\);$")
 clone_fns = set()
 constructor_fns = {}
 c_array_class_caches = set()
 clone_fns = set()
 constructor_fns = {}
 c_array_class_caches = set()

+
+
+from gen_type_mapping import TypeMappingGenerator
+type_mapping_generator = TypeMappingGenerator(java_c_types, consts, c_array_class_caches, opaque_structs, clone_fns, unitary_enums, trait_structs, complex_enums, result_types, tuple_types)
+
+
+

 with open(sys.argv[1]) as in_h:
     for line in in_h:
         reg_fn = reg_fn_regex.match(line)
 with open(sys.argv[1]) as in_h:
     for line in in_h:
         reg_fn = reg_fn_regex.match(line)


@@ -500,392 +356,31 @@ with open(sys.argv[1]) as in_h:
                 clone_fns.add(arr_fn.group(2))
             # No object constructors return arrays, as then they wouldn't be an object constructor
             continue
                 clone_fns.add(arr_fn.group(2))
             # No object constructors return arrays, as then they wouldn't be an object constructor
             continue

-java_c_types_none_allowed = False # C structs created by cbindgen are declared in dependency order

 
 

-with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
-    def map_type(fn_arg, print_void, ret_arr_len, is_free, holds_ref):
-        ty_info = java_c_types(fn_arg, ret_arr_len)
-        return map_type_with_info(ty_info, print_void, ret_arr_len, is_free, holds_ref)
-
-    def map_type_with_info(ty_info, print_void, ret_arr_len, is_free, holds_ref):
-        if ty_info.c_ty == "void":
-            if not print_void:
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = None, arg_conv_name = None, arg_conv_cleanup = None,
-                    ret_conv = None, ret_conv_name = None, to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
-        if ty_info.c_ty.endswith("Array"):
-            arr_len = ty_info.arr_len
-            if arr_len is not None:
-                arr_name = ty_info.var_name
-            else:
-                arr_name = "ret"
-                arr_len = ret_arr_len
-            if ty_info.c_ty == "jbyteArray":
-                ret_conv = ("jbyteArray " + arr_name + "_arr = (*_env)->NewByteArray(_env, " + arr_len + ");\n" + "(*_env)->SetByteArrayRegion(_env, " + arr_name + "_arr, 0, " + arr_len + ", ", "")
-                arg_conv_cleanup = None
-                if not arr_len.isdigit():
-                    arg_conv = ty_info.rust_obj + " " + arr_name + "_ref;\n"
-                    arg_conv = arg_conv + arr_name + "_ref." + arr_len + " = (*_env)->GetArrayLength (_env, " + arr_name + ");\n"
-                    if (not ty_info.is_ptr or not holds_ref) and ty_info.rust_obj != "LDKu8slice":
-                        arg_conv = arg_conv + arr_name + "_ref." + ty_info.arr_access + " = MALLOC(" + arr_name + "_ref." + arr_len + ", \"" + ty_info.rust_obj + " Bytes\");\n"
-                        arg_conv = arg_conv + "(*_env)->GetByteArrayRegion(_env, " + arr_name + ", 0, " + arr_name + "_ref." + arr_len + ", " + arr_name + "_ref." + ty_info.arr_access + ");"
-                    else:
-                        arg_conv = arg_conv + arr_name + "_ref." + ty_info.arr_access + " = (*_env)->GetByteArrayElements (_env, " + arr_name + ", NULL);"
-                        arg_conv_cleanup = "(*_env)->ReleaseByteArrayElements(_env, " + arr_name + ", (int8_t*)" + arr_name + "_ref." + ty_info.arr_access + ", 0);"
-                    if ty_info.rust_obj == "LDKTransaction":
-                        arg_conv = arg_conv + "\n" + arr_name + "_ref.data_is_owned = " + str(holds_ref).lower() + ";"
-                    ret_conv = (ty_info.rust_obj + " " + arr_name + "_var = ", "")
-                    ret_conv = (ret_conv[0], ";\njbyteArray " + arr_name + "_arr = (*_env)->NewByteArray(_env, " + arr_name + "_var." + arr_len + ");\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + "(*_env)->SetByteArrayRegion(_env, " + arr_name + "_arr, 0, " + arr_name + "_var." + arr_len + ", " + arr_name + "_var." + ty_info.arr_access + ");")
-                    if not holds_ref and ty_info.rust_obj != "LDKu8slice":
-                        ret_conv = (ret_conv[0], ret_conv[1] + "\n" + ty_info.rust_obj.replace("LDK", "") + "_free(" + arr_name + "_var);")
-                elif ty_info.rust_obj is not None:
-                    arg_conv = ty_info.rust_obj + " " + arr_name + "_ref;\n"
-                    arg_conv = arg_conv + "CHECK((*_env)->GetArrayLength (_env, " + arr_name + ") == " + arr_len + ");\n"
-                    arg_conv = arg_conv + "(*_env)->GetByteArrayRegion (_env, " + arr_name + ", 0, " + arr_len + ", " + arr_name + "_ref." + ty_info.arr_access + ");"
-                    ret_conv = (ret_conv[0], "." + ty_info.arr_access + ");")
-                else:
-                    arg_conv = "unsigned char " + arr_name + "_arr[" + arr_len + "];\n"
-                    arg_conv = arg_conv + "CHECK((*_env)->GetArrayLength (_env, " + arr_name + ") == " + arr_len + ");\n"
-                    arg_conv = arg_conv + "(*_env)->GetByteArrayRegion (_env, " + arr_name + ", 0, " + arr_len + ", " + arr_name + "_arr);\n" + "unsigned char (*" + arr_name + "_ref)[" + arr_len + "] = &" + arr_name + "_arr;"
-                    ret_conv = (ret_conv[0] + "*", ");")
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = arg_conv, arg_conv_name = arr_name + "_ref", arg_conv_cleanup = arg_conv_cleanup,
-                    ret_conv = ret_conv, ret_conv_name = arr_name + "_arr", to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
-            else:
-                assert not arr_len.isdigit() # fixed length arrays not implemented
-                assert ty_info.java_ty[len(ty_info.java_ty) - 2:] == "[]"
-                conv_name = "arr_conv_" + str(len(ty_info.java_hu_ty))
-                idxc = chr(ord('a') + (len(ty_info.java_hu_ty) % 26))
-                ty_info.subty.var_name = conv_name
-                if ty_info.is_ptr or holds_ref:
-                    ty_info.subty.requires_clone = False
-                subty = map_type_with_info(ty_info.subty, False, None, is_free, holds_ref)
-                if arr_name == "":
-                    arr_name = "arg"
-                arg_conv = ty_info.rust_obj + " " + arr_name + "_constr;\n"
-                arg_conv = arg_conv + arr_name + "_constr." + arr_len + " = (*_env)->GetArrayLength (_env, " + arr_name + ");\n"
-                arg_conv = arg_conv + "if (" + arr_name + "_constr." + arr_len + " > 0)\n"
-                if subty.rust_obj is None:
-                    szof = subty.c_ty
-                else:
-                    szof = subty.rust_obj
-                arg_conv = arg_conv + "\t" + arr_name + "_constr." + ty_info.arr_access + " = MALLOC(" + arr_name + "_constr." + arr_len + " * sizeof(" + szof + "), \"" + ty_info.rust_obj + " Elements\");\n"
-                arg_conv = arg_conv + "else\n"
-                arg_conv = arg_conv + "\t" + arr_name + "_constr." + ty_info.arr_access + " = NULL;\n"
-                if not ty_info.java_ty[:len(ty_info.java_ty) - 2].endswith("[]"):
-                    arg_conv = arg_conv + ty_info.java_ty.strip("[]") + "* " + arr_name + "_vals = (*_env)->Get" + ty_info.subty.java_ty.title() + "ArrayElements (_env, " + arr_name + ", NULL);\n"
-                arg_conv = arg_conv + "for (size_t " + idxc + " = 0; " + idxc + " < " + arr_name + "_constr." + arr_len + "; " + idxc + "++) {\n"
-                if not ty_info.java_ty[:len(ty_info.java_ty) - 2].endswith("[]"):
-                    arg_conv = arg_conv + "\t" + ty_info.java_ty.strip("[]") + " " + conv_name + " = " + arr_name + "_vals[" + idxc + "];"
-                    if subty.arg_conv is not None:
-                        arg_conv = arg_conv + "\n\t" + subty.arg_conv.replace("\n", "\n\t")
-                else:
-                    arg_conv = arg_conv + "\tjobject " + conv_name + " = (*_env)->GetObjectArrayElement(_env, " + arr_name + ", " + idxc + ");\n"
-                    arg_conv = arg_conv + "\t" + subty.arg_conv.replace("\n", "\n\t")
-                arg_conv = arg_conv + "\n\t" + arr_name + "_constr." + ty_info.arr_access + "[" + idxc + "] = " + subty.arg_conv_name + ";\n}"
-                if not ty_info.java_ty[:len(ty_info.java_ty) - 2].endswith("[]"):
-                    arg_conv = arg_conv + "\n(*_env)->Release" + ty_info.java_ty.strip("[]").title() + "ArrayElements (_env, " + arr_name + ", " + arr_name + "_vals, 0);"
-                if ty_info.is_ptr:
-                    arg_conv_name = "&" + arr_name + "_constr"
-                else:
-                    arg_conv_name = arr_name + "_constr"
-                arg_conv_cleanup = None
-                if ty_info.is_ptr:
-                    arg_conv_cleanup = "FREE(" + arr_name + "_constr." + ty_info.arr_access + ");"
-
-                if arr_name == "arg":
-                    arr_name = "ret"
-                ret_conv = (ty_info.rust_obj + " " + arr_name + "_var = ", "")
-                if subty.ret_conv is None:
-                    ret_conv = ("DUMMY", "DUMMY")
-                elif not ty_info.java_ty[:len(ty_info.java_ty) - 2].endswith("[]"):
-                    ret_conv = (ret_conv[0], ";\n" + ty_info.c_ty + " " + arr_name + "_arr = (*_env)->New" + ty_info.java_ty.strip("[]").title() + "Array(_env, " + arr_name + "_var." + arr_len + ");\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + subty.c_ty + " *" + arr_name + "_arr_ptr = (*_env)->GetPrimitiveArrayCritical(_env, " + arr_name + "_arr, NULL);\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + "for (size_t " + idxc + " = 0; " + idxc + " < " + arr_name + "_var." + arr_len + "; " + idxc + "++) {\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + "\t" + subty.ret_conv[0].replace("\n", "\n\t"))
-                    ret_conv = (ret_conv[0], ret_conv[1] + arr_name + "_var." + ty_info.arr_access + "[" + idxc + "]" + subty.ret_conv[1].replace("\n", "\n\t"))
-                    ret_conv = (ret_conv[0], ret_conv[1] + "\n\t" + arr_name + "_arr_ptr[" + idxc + "] = " + subty.ret_conv_name + ";\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + "}\n(*_env)->ReleasePrimitiveArrayCritical(_env, " + arr_name + "_arr, " + arr_name + "_arr_ptr, 0);")
-                else:
-                    assert ty_info.java_fn_ty_arg.startswith("[")
-                    clz_var = ty_info.java_fn_ty_arg[1:].replace("[", "arr_of_")
-                    c_array_class_caches.add(clz_var)
-                    ret_conv = (ret_conv[0], ";\n" + ty_info.c_ty + " " + arr_name + "_arr = (*_env)->NewObjectArray(_env, " + arr_name + "_var." + arr_len + ", " + clz_var + "_clz, NULL);\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + "for (size_t " + idxc + " = 0; " + idxc + " < " + arr_name + "_var." + arr_len + "; " + idxc + "++) {\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + "\t" + subty.ret_conv[0].replace("\n", "\n\t"))
-                    ret_conv = (ret_conv[0], ret_conv[1] + arr_name + "_var." + ty_info.arr_access + "[" + idxc + "]" + subty.ret_conv[1].replace("\n", "\n\t"))
-                    ret_conv = (ret_conv[0], ret_conv[1] + "\n\t(*_env)->SetObjectArrayElement(_env, " + arr_name + "_arr, " + idxc + ", " + subty.ret_conv_name + ");\n")
-                    ret_conv = (ret_conv[0], ret_conv[1] + "}")
-                if not holds_ref:
-                    # Note that we don't drop the full vec here - we're passing ownership to java (or have cloned) or free'd by now!
-                    ret_conv = (ret_conv[0], ret_conv[1] + "\nFREE(" + arr_name + "_var." + ty_info.arr_access + ");")
-
-                to_hu_conv = None
-                to_hu_conv_name = None
-                if subty.to_hu_conv is not None:
-                    to_hu_conv = ty_info.java_hu_ty + " " + conv_name + "_arr = new " + ty_info.subty.java_hu_ty.split("<")[0] + "[" + arr_name + ".length];\n"
-                    to_hu_conv = to_hu_conv + "for (int " + idxc + " = 0; " + idxc + " < " + arr_name + ".length; " + idxc + "++) {\n"
-                    to_hu_conv = to_hu_conv + "\t" + subty.java_ty + " " + conv_name + " = " + arr_name + "[" + idxc + "];\n"
-                    to_hu_conv = to_hu_conv + "\t" + subty.to_hu_conv.replace("\n", "\n\t") + "\n"
-                    to_hu_conv = to_hu_conv + "\t" + conv_name + "_arr[" + idxc + "] = " + subty.to_hu_conv_name + ";\n}"
-                    to_hu_conv_name = conv_name + "_arr"
-                from_hu_conv = None
-                if subty.from_hu_conv is not None:
-                    if subty.java_ty == "long" and subty.java_hu_ty != "long":
-                        from_hu_conv = ("Arrays.stream(" + arr_name + ").mapToLong(" + conv_name + " -> " + subty.from_hu_conv[0] + ").toArray()", "/* TODO 2 " + subty.java_hu_ty + "  */")
-                    elif subty.java_ty == "long":
-                        from_hu_conv = ("Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + subty.from_hu_conv[0] + ").toArray()", "/* TODO 2 " + subty.java_hu_ty + "  */")
-                    else:
-                        from_hu_conv = ("(" + ty_info.java_ty + ")Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + subty.from_hu_conv[0] + ").toArray()", "/* TODO 2 " + subty.java_hu_ty + "  */")
-
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = arg_conv, arg_conv_name = arg_conv_name, arg_conv_cleanup = arg_conv_cleanup,
-                    ret_conv = ret_conv, ret_conv_name = arr_name + "_arr", to_hu_conv = to_hu_conv, to_hu_conv_name = to_hu_conv_name, from_hu_conv = from_hu_conv)
-        elif ty_info.java_ty == "String":
-            if ty_info.arr_access is None:
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = None, arg_conv_name = None, arg_conv_cleanup = None,
-                    ret_conv = ("jstring " + ty_info.var_name + "_conv = (*_env)->NewStringUTF(_env, ", ");"), ret_conv_name = ty_info.var_name + "_conv",
-                    to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
-            else:
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = None, arg_conv_name = None, arg_conv_cleanup = None,
-                    ret_conv = ("LDKStr " + ty_info.var_name + "_str = ",
-                        ";\nchar* " + ty_info.var_name + "_buf = MALLOC(" + ty_info.var_name + "_str." + ty_info.arr_len + " + 1, \"str conv buf\");\n" +
-                        "memcpy(" + ty_info.var_name + "_buf, " + ty_info.var_name + "_str." + ty_info.arr_access + ", " + ty_info.var_name + "_str." + ty_info.arr_len + ");\n" +
-                        ty_info.var_name + "_buf[" + ty_info.var_name + "_str." + ty_info.arr_len + "] = 0;\n" +
-                        "jstring " + ty_info.var_name + "_conv = (*_env)->NewStringUTF(_env, " + ty_info.var_name + "_str." + ty_info.arr_access + ");\n" +
-                        "FREE(" + ty_info.var_name + "_buf);"),
-                    ret_conv_name = ty_info.var_name + "_conv", to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
-        elif ty_info.var_name == "" and not print_void:
-            # We don't have a parameter name, and want one, just call it arg
-            if ty_info.rust_obj is not None:
-                assert(not is_free or ty_info.rust_obj not in opaque_structs)
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = ty_info.rust_obj + " arg_conv = *(" + ty_info.rust_obj + "*)arg;\nFREE((void*)arg);",
-                    arg_conv_name = "arg_conv", arg_conv_cleanup = None,
-                    ret_conv = None, ret_conv_name = None, to_hu_conv = "TODO 7", to_hu_conv_name = None, from_hu_conv = None)
-            else:
-                assert(not is_free)
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = None, arg_conv_name = "arg", arg_conv_cleanup = None,
-                    ret_conv = None, ret_conv_name = None, to_hu_conv = "TODO 8", to_hu_conv_name = None, from_hu_conv = None)
-        elif ty_info.rust_obj is None:
-            return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                arg_conv = None, arg_conv_name = ty_info.var_name, arg_conv_cleanup = None,
-                ret_conv = None, ret_conv_name = None, to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
-        else:
-            if ty_info.var_name == "":
-                ty_info.var_name = "ret"
-
-            if ty_info.rust_obj in opaque_structs:
-                opaque_arg_conv = ty_info.rust_obj + " " + ty_info.var_name + "_conv;\n"
-                opaque_arg_conv = opaque_arg_conv + ty_info.var_name + "_conv.inner = (void*)(" + ty_info.var_name + " & (~1));\n"
-                if ty_info.is_ptr and holds_ref:
-                    opaque_arg_conv = opaque_arg_conv + ty_info.var_name + "_conv.is_owned = false;"
-                else:
-                    opaque_arg_conv = opaque_arg_conv + ty_info.var_name + "_conv.is_owned = (" + ty_info.var_name + " & 1) || (" + ty_info.var_name + " == 0);"
-                if not is_free and (not ty_info.is_ptr or not holds_ref or ty_info.requires_clone == True) and ty_info.requires_clone != False:
-                    if (ty_info.java_hu_ty + "_clone") in clone_fns:
-                        # TODO: This is a bit too naive, even with the checks above, we really need to know if rust wants a ref or not, not just if its pass as a ptr.
-                        opaque_arg_conv = opaque_arg_conv + "\nif (" + ty_info.var_name + "_conv.inner != NULL)\n"
-                        opaque_arg_conv = opaque_arg_conv + "\t" + ty_info.var_name + "_conv = " + ty_info.java_hu_ty + "_clone(&" + ty_info.var_name + "_conv);"
-                    elif ty_info.passed_as_ptr:
-                        opaque_arg_conv = opaque_arg_conv + "\n// Warning: we may need a move here but can't clone!"
-
-                opaque_ret_conv_suf = ";\n"
-                if not holds_ref and ty_info.is_ptr and (ty_info.java_hu_ty + "_clone") in clone_fns: # is_ptr, not holds_ref implies passing a pointed-to value to java, which needs copied
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "if (" + ty_info.var_name + "->inner != NULL)\n"
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "\t" + ty_info.var_name + "_var = " + ty_info.java_hu_ty + "_clone(" + ty_info.var_name + ");\n"
-                elif not holds_ref and ty_info.is_ptr:
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "// Warning: we may need a move here but can't clone!\n"
-
-                opaque_ret_conv_suf = opaque_ret_conv_suf + "CHECK((((long)" + ty_info.var_name + "_var.inner) & 1) == 0); // We rely on a free low bit, malloc guarantees this.\n"
-                opaque_ret_conv_suf = opaque_ret_conv_suf + "CHECK((((long)&" + ty_info.var_name + "_var) & 1) == 0); // We rely on a free low bit, pointer alignment guarantees this.\n"
-                if holds_ref:
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "long " + ty_info.var_name + "_ref = (long)" + ty_info.var_name + "_var.inner & ~1;"
-                else:
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "long " + ty_info.var_name + "_ref = (long)" + ty_info.var_name + "_var.inner;\n"
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "if (" + ty_info.var_name + "_var.is_owned) {\n"
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "\t" + ty_info.var_name + "_ref |= 1;\n"
-                    opaque_ret_conv_suf = opaque_ret_conv_suf + "}"
-
-                if ty_info.is_ptr:
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = opaque_arg_conv, arg_conv_name = "&" + ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                        ret_conv = (ty_info.rust_obj + " " + ty_info.var_name + "_var = *", opaque_ret_conv_suf),
-                        ret_conv_name = ty_info.var_name + "_ref",
-                        to_hu_conv = ty_info.java_hu_ty + " " + ty_info.var_name + "_hu_conv = new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ");",
-                        to_hu_conv_name = ty_info.var_name + "_hu_conv",
-                        from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".ptr & ~1", "this.ptrs_to.add(" + ty_info.var_name + ")"))
-                else:
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = opaque_arg_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                        ret_conv = (ty_info.rust_obj + " " + ty_info.var_name + "_var = ", opaque_ret_conv_suf),
-                        ret_conv_name = ty_info.var_name + "_ref",
-                        to_hu_conv = ty_info.java_hu_ty + " " + ty_info.var_name + "_hu_conv = new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ");",
-                        to_hu_conv_name = ty_info.var_name + "_hu_conv",
-                        from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".ptr & ~1", "this.ptrs_to.add(" + ty_info.var_name + ")"))
-
-            if not ty_info.is_ptr:
-                if ty_info.rust_obj in unitary_enums:
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = ty_info.rust_obj + " " + ty_info.var_name + "_conv = " + ty_info.rust_obj + "_from_java(_env, " + ty_info.var_name + ");",
-                        arg_conv_name = ty_info.var_name + "_conv",
-                        arg_conv_cleanup = None,
-                        ret_conv = ("jclass " + ty_info.var_name + "_conv = " + ty_info.rust_obj + "_to_java(_env, ", ");"),
-                        ret_conv_name = ty_info.var_name + "_conv", to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
-                base_conv = ty_info.rust_obj + " " + ty_info.var_name + "_conv = *(" + ty_info.rust_obj + "*)" + ty_info.var_name + ";"
-                if ty_info.rust_obj in trait_structs:
-                    if not is_free:
-                        needs_full_clone = not is_free and (not ty_info.is_ptr and not holds_ref or ty_info.requires_clone == True) and ty_info.requires_clone != False
-                        if needs_full_clone and (ty_info.java_hu_ty + "_clone") in clone_fns:
-                            base_conv = base_conv + "\n" + ty_info.var_name + "_conv = " + ty_info.java_hu_ty + "_clone(" + ty_info.var_name + ");"
-                        else:
-                            base_conv = base_conv + "\nif (" + ty_info.var_name + "_conv.free == " + ty_info.rust_obj + "_JCalls_free) {\n"
-                            base_conv = base_conv + "\t// If this_arg is a JCalls struct, then we need to increment the refcnt in it.\n"
-                            base_conv = base_conv + "\t" + ty_info.rust_obj + "_JCalls_clone(" + ty_info.var_name + "_conv.this_arg);\n}"
-                            if needs_full_clone:
-                                base_conv = base_conv + "// Warning: we may need a move here but can't do a full clone!\n"
+# Define some manual clones...
+clone_fns.add("ThirtyTwoBytes_clone")
+write_c("static inline struct LDKThirtyTwoBytes ThirtyTwoBytes_clone(const struct LDKThirtyTwoBytes *orig) { struct LDKThirtyTwoBytes ret; memcpy(ret.data, orig->data, 32); return ret; }\n")

 
 

-                    else:
-                        base_conv = base_conv + "\n" + "FREE((void*)" + ty_info.var_name + ");"
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                        ret_conv = (ty_info.rust_obj + "* ret = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*ret = ", ";"),
-                        ret_conv_name = "(long)ret",
-                        to_hu_conv = ty_info.java_hu_ty + " ret_hu_conv = new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ");\nret_hu_conv.ptrs_to.add(this);",
-                        to_hu_conv_name = "ret_hu_conv",
-                        from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".ptr", "this.ptrs_to.add(" + ty_info.var_name + ")"))
-                if ty_info.rust_obj != "LDKu8slice":
-                    # Don't bother free'ing slices passed in - Rust doesn't auto-free the
-                    # underlying unlike Vecs, and it gives Java more freedom.
-                    base_conv = base_conv + "\nFREE((void*)" + ty_info.var_name + ");";
-                if ty_info.rust_obj in complex_enums:
-                    ret_conv = ("long " + ty_info.var_name + "_ref = (long)&", ";")
-                    if not holds_ref:
-                        ret_conv = (ty_info.rust_obj + " *" + ty_info.var_name + "_copy = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n", "")
-                        if ty_info.requires_clone == True: # Set in object array mapping
-                            if (ty_info.java_hu_ty + "_clone") in clone_fns:
-                                ret_conv = (ret_conv[0] + "*" + ty_info.var_name + "_copy = " + ty_info.java_hu_ty + "_clone(&", ");\n")
-                            else:
-                                ret_conv = (ret_conv[0] + "*" + ty_info.var_name + "_copy = ", "; // XXX: We likely need to clone here, but no _clone fn is available!\n")
-                        else:
-                            ret_conv = (ret_conv[0] + "*" + ty_info.var_name + "_copy = ", ";\n")
-                        ret_conv = (ret_conv[0], ret_conv[1] + "long " + ty_info.var_name + "_ref = (long)" + ty_info.var_name + "_copy;")
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                        ret_conv = ret_conv, ret_conv_name = ty_info.var_name + "_ref",
-                        to_hu_conv = ty_info.java_hu_ty + " " + ty_info.var_name + "_hu_conv = " + ty_info.java_hu_ty + ".constr_from_ptr(" + ty_info.var_name + ");\n" + ty_info.var_name + "_hu_conv.ptrs_to.add(this);",
-                        to_hu_conv_name = ty_info.var_name + "_hu_conv", from_hu_conv = (ty_info.var_name + ".ptr", ""))
-                if ty_info.rust_obj in result_types:
-                    #assert not ty_info.is_ptr and not holds_ref # Otherwise we shouldn't be MALLOC'ing
-                    # XXX ^
-                    ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_conv = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*" + ty_info.var_name + "_conv = ", ";")
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                        ret_conv = ret_conv, ret_conv_name = "(long)" + ty_info.var_name + "_conv",
-                        to_hu_conv = ty_info.java_hu_ty + " " + ty_info.var_name + "_hu_conv = " + ty_info.java_hu_ty + ".constr_from_ptr(" + ty_info.var_name + ");",
-                        to_hu_conv_name = ty_info.var_name + "_hu_conv", from_hu_conv = (ty_info.var_name + " != null ? " + ty_info.var_name + ".ptr : 0", ""))
-                if ty_info.rust_obj in tuple_types:
-                    from_hu_conv = "bindings." + tuple_types[ty_info.rust_obj][1].replace("LDK", "") + "_new("
-                    to_hu_conv_pfx = ""
-                    to_hu_conv_sfx = ty_info.java_hu_ty + " " + ty_info.var_name + "_conv = new " + ty_info.java_hu_ty + "("
-                    for idx, conv in enumerate(tuple_types[ty_info.rust_obj][0]):
-                        if idx != 0:
-                            to_hu_conv_sfx = to_hu_conv_sfx + ", "
-                            from_hu_conv = from_hu_conv + ", "
-                        conv.var_name = ty_info.var_name + "_" + chr(idx + ord("a"))
-                        conv_map = map_type_with_info(conv, False, None, is_free, holds_ref)
-                        to_hu_conv_pfx = to_hu_conv_pfx + conv.java_ty + " " + ty_info.var_name + "_" + chr(idx + ord("a")) + " = " + "bindings." + tuple_types[ty_info.rust_obj][1] + "_get_" + chr(idx + ord("a")) + "(" + ty_info.var_name + ");\n"
-                        if conv_map.to_hu_conv is not None:
-                            to_hu_conv_pfx = to_hu_conv_pfx + conv_map.to_hu_conv + ";\n"
-                            to_hu_conv_sfx = to_hu_conv_sfx + conv_map.to_hu_conv_name
-                        else:
-                            to_hu_conv_sfx = to_hu_conv_sfx + ty_info.var_name + "_" + chr(idx + ord("a"))
-                        if conv_map.from_hu_conv is not None:
-                            from_hu_conv = from_hu_conv + conv_map.from_hu_conv[0].replace(ty_info.var_name + "_" + chr(idx + ord("a")), ty_info.var_name + "." + chr(idx + ord("a")))
-                            if conv_map.from_hu_conv[1] != "":
-                                from_hu_conv = from_hu_conv + "/*XXX: " + conv_map.from_hu_conv[1] + "*/"
-                        else:
-                            from_hu_conv = from_hu_conv + ty_info.var_name + "." + chr(idx + ord("a"))
-
-                    if not ty_info.is_ptr and not holds_ref:
-                        return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                            arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-
-                            ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_ref = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*" + ty_info.var_name + "_ref = ", ";"),
-                            ret_conv_name = "(long)" + ty_info.var_name + "_ref",
-                            to_hu_conv = to_hu_conv_pfx + to_hu_conv_sfx + ");", to_hu_conv_name = ty_info.var_name + "_conv", from_hu_conv = (from_hu_conv + ")", ""))
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                        ret_conv = ("long " + ty_info.var_name + "_ref = (long)&", ";"), ret_conv_name = ty_info.var_name + "_ref",
-                        to_hu_conv = to_hu_conv_pfx + to_hu_conv_sfx + ");", to_hu_conv_name = ty_info.var_name + "_conv", from_hu_conv = (from_hu_conv + ")", ""))
-
-                # The manually-defined types - TxOut and Transaction
-                assert ty_info.rust_obj == "LDKTxOut"
-                if not ty_info.is_ptr and not holds_ref:
-                    ret_conv = ("LDKTxOut* " + ty_info.var_name + "_ref = MALLOC(sizeof(LDKTxOut), \"LDKTxOut\");\n*" + ty_info.var_name + "_ref = ", ";")
-                else:
-                    ret_conv = ("long " + ty_info.var_name + "_ref = (long)&", ";")
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                    ret_conv = ret_conv, ret_conv_name = "(long)" + ty_info.var_name + "_ref",
-                    to_hu_conv = ty_info.java_hu_ty + " " + ty_info.var_name + "_conv = new " +ty_info.java_hu_ty + "(null, " + ty_info.var_name + ");",
-                    to_hu_conv_name = ty_info.var_name + "_conv", from_hu_conv = (ty_info.var_name + ".ptr", ""))
-            elif ty_info.is_ptr:
-                assert(not is_free)
-                if ty_info.rust_obj in complex_enums:
-                    return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                        arg_conv = ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)" + ty_info.var_name + ";",
-                        arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                        ret_conv = ("long ret_" + ty_info.var_name + " = (long)", ";"), ret_conv_name = "ret_" + ty_info.var_name,
-                        to_hu_conv = ty_info.java_hu_ty + " " + ty_info.var_name + "_hu_conv = " + ty_info.java_hu_ty + ".constr_from_ptr(" + ty_info.var_name + ");",
-                        to_hu_conv_name = ty_info.var_name + "_hu_conv",
-                        from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".ptr & ~1", "this.ptrs_to.add(" + ty_info.var_name + ")"))
-                elif ty_info.rust_obj in trait_structs:
-                    if ty_info.java_hu_ty + "_clone" in clone_fns:
-                        return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                            arg_conv = ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)" + ty_info.var_name + ";",
-                            arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                            ret_conv = (ty_info.rust_obj + " *" + ty_info.var_name + "_clone = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n" +
-                                "*" + ty_info.var_name + "_clone = " + ty_info.java_hu_ty + "_clone(", ");"),
-                            ret_conv_name = "(long)" + ty_info.var_name + "_clone",
-                            to_hu_conv = ty_info.java_hu_ty + " ret_hu_conv = new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ");\nret_hu_conv.ptrs_to.add(this);",
-                            to_hu_conv_name = "ret_hu_conv",
-                            from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".ptr", "this.ptrs_to.add(" + ty_info.var_name + ")"))
-                    else:
-                        return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                            arg_conv = ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)" + ty_info.var_name + ";",
-                            arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                            ret_conv = ("long ret_" + ty_info.var_name + " = (long)", ";"), ret_conv_name = "ret_" + ty_info.var_name,
-                            to_hu_conv = ty_info.java_hu_ty + " ret_hu_conv = new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ");\nret_hu_conv.ptrs_to.add(this);",
-                            to_hu_conv_name = "ret_hu_conv",
-                            from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".ptr", "this.ptrs_to.add(" + ty_info.var_name + ")"))
-                return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
-                    arg_conv = ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)" + ty_info.var_name + ";",
-                    arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
-                    ret_conv = ("long ret_" + ty_info.var_name + " = (long)", ";"), ret_conv_name = "ret_" + ty_info.var_name,
-                    to_hu_conv = "TODO 3", to_hu_conv_name = None, from_hu_conv = None) # its a pointer, no conv needed
-            assert False # We should have handled every case by now.
+java_c_types_none_allowed = False # C structs created by cbindgen are declared in dependency order

 
 

+with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:

     def map_fn(line, re_match, ret_arr_len, c_call_string):
         out_java.write("\t// " + line)
         out_java.write("\tpublic static native ")
     def map_fn(line, re_match, ret_arr_len, c_call_string):
         out_java.write("\t// " + line)
         out_java.write("\tpublic static native ")

-        write_c("JNIEXPORT ")
+        write_c(consts.c_fn_ty_pfx)

 
         is_free = re_match.group(2).endswith("_free")
         struct_meth = re_match.group(2).split("_")[0]
 
 
         is_free = re_match.group(2).endswith("_free")
         struct_meth = re_match.group(2).split("_")[0]
 

-        ret_info = map_type(re_match.group(1), True, ret_arr_len, False, False)
-        ret_info.print_ty()
+        ret_info = type_mapping_generator.map_type(re_match.group(1), True, ret_arr_len, False, False)
+        write_c(ret_info.c_ty)
+        out_java.write(ret_info.java_ty)

 
         if ret_info.ret_conv is not None:
             ret_conv_pfx, ret_conv_sfx = ret_info.ret_conv
 
         out_java.write(" " + re_match.group(2) + "(")
 
         if ret_info.ret_conv is not None:
             ret_conv_pfx, ret_conv_sfx = ret_info.ret_conv
 
         out_java.write(" " + re_match.group(2) + "(")

-        write_c(" JNICALL Java_org_ldk_impl_bindings_" + re_match.group(2).replace('_', '_1') + "(JNIEnv * _env, jclass _b")
+        write_c(" " + consts.c_fn_name_pfx + re_match.group(2).replace('_', '_1') + "(" + consts.c_fn_args_pfx)

 
         arg_names = []
         default_constructor_args = {}
 
         arg_names = []
         default_constructor_args = {}


@@ -896,17 +391,17 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
                 out_java.write(", ")
             if arg != "void":
                 write_c(", ")
                 out_java.write(", ")
             if arg != "void":
                 write_c(", ")

-            arg_conv_info = map_type(arg, False, None, is_free, True)
+            arg_conv_info = type_mapping_generator.map_type(arg, False, None, is_free, True)

             if arg_conv_info.c_ty != "void":
             if arg_conv_info.c_ty != "void":

-                arg_conv_info.print_ty()
-                arg_conv_info.print_name()
+                write_c(arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
+                out_java.write(arg_conv_info.java_ty + " " + arg_conv_info.arg_name)

             if idx == 0 and arg_conv_info.java_hu_ty == struct_meth:
                 takes_self = True
             if arg_conv_info.arg_conv is not None and "Warning" in arg_conv_info.arg_conv:
                 if arg_conv_info.rust_obj in constructor_fns:
                     assert not is_free
                     for explode_arg in constructor_fns[arg_conv_info.rust_obj].split(','):
             if idx == 0 and arg_conv_info.java_hu_ty == struct_meth:
                 takes_self = True
             if arg_conv_info.arg_conv is not None and "Warning" in arg_conv_info.arg_conv:
                 if arg_conv_info.rust_obj in constructor_fns:
                     assert not is_free
                     for explode_arg in constructor_fns[arg_conv_info.rust_obj].split(','):

-                        explode_arg_conv = map_type(explode_arg, False, None, False, True)
+                        explode_arg_conv = type_mapping_generator.map_type(explode_arg, False, None, False, True)

                         if explode_arg_conv.c_ty == "void":
                             # We actually want to handle this case, but for now its only used in NetGraphMsgHandler::new()
                             # which ends up resulting in a redundant constructor - both without arguments for the NetworkGraph.
                         if explode_arg_conv.c_ty == "void":
                             # We actually want to handle this case, but for now its only used in NetGraphMsgHandler::new()
                             # which ends up resulting in a redundant constructor - both without arguments for the NetworkGraph.


@@ -919,7 +414,7 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
 
         out_java_struct = None
         if ("LDK" + struct_meth in opaque_structs or "LDK" + struct_meth in trait_structs) and not is_free:
 
         out_java_struct = None
         if ("LDK" + struct_meth in opaque_structs or "LDK" + struct_meth in trait_structs) and not is_free:

-            out_java_struct = open(sys.argv[3] + "/structs/" + struct_meth + ".java", "a")
+            out_java_struct = open(f"{sys.argv[3]}/structs/{struct_meth}{consts.file_ext}", "a")

             if not args_known:
                 out_java_struct.write("\t// Skipped " + re_match.group(2) + "\n")
                 out_java_struct.close()
             if not args_known:
                 out_java_struct.write("\t// Skipped " + re_match.group(2) + "\n")
                 out_java_struct.close()


@@ -1040,425 +535,87 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
             out_java_struct.close()
 
     def map_unitary_enum(struct_name, field_lines):
             out_java_struct.close()
 
     def map_unitary_enum(struct_name, field_lines):

-        with open(sys.argv[3] + "/enums/" + struct_name + ".java", "w") as out_java_enum:
-            out_java_enum.write("package org.ldk.enums;\n\n")
+        with open(f"{sys.argv[3]}/enums/{struct_name}{consts.file_ext}", "w") as out_java_enum:

             unitary_enums.add(struct_name)
             unitary_enums.add(struct_name)

-            write_c("static inline " + struct_name + " " + struct_name + "_from_java(JNIEnv *env, jclass val) {\n")
-            write_c("\tswitch ((*env)->CallIntMethod(env, val, ordinal_meth)) {\n")
-            ord_v = 0

             for idx, struct_line in enumerate(field_lines):
                 if idx == 0:
             for idx, struct_line in enumerate(field_lines):
                 if idx == 0:

-                    out_java_enum.write("public enum " + struct_name + " {\n")
+                    assert(struct_line == "typedef enum %s {" % struct_name)

                 elif idx == len(field_lines) - 3:
                     assert(struct_line.endswith("_Sentinel,"))
                 elif idx == len(field_lines) - 2:
                 elif idx == len(field_lines) - 3:
                     assert(struct_line.endswith("_Sentinel,"))
                 elif idx == len(field_lines) - 2:

-                    out_java_enum.write("\t; static native void init();\n")
-                    out_java_enum.write("\tstatic { init(); }\n")
-                    out_java_enum.write("}")
-                    out_java.write("\tstatic { " + struct_name + ".values(); /* Force enum statics to run */ }\n")
+                    assert(struct_line == "} %s;" % struct_name)

                 elif idx == len(field_lines) - 1:
                     assert(struct_line == "")
                 elif idx == len(field_lines) - 1:
                     assert(struct_line == "")

-                else:
-                    out_java_enum.write(struct_line + "\n")
-                    write_c("\t\tcase %d: return %s;\n" % (ord_v, struct_line.strip().strip(",")))
-                    ord_v = ord_v + 1
-            write_c("\t}\n")
-            write_c("\tabort();\n")
-            write_c("}\n")
-
-            ord_v = 0
-            write_c("static jclass " + struct_name + "_class = NULL;\n")
-            for idx, struct_line in enumerate(field_lines):
-                if idx > 0 and idx < len(field_lines) - 3:
-                    variant = struct_line.strip().strip(",")
-                    write_c("static jfieldID " + struct_name + "_" + variant + " = NULL;\n")
-            write_c("JNIEXPORT void JNICALL Java_org_ldk_enums_" + struct_name.replace("_", "_1") + "_init (JNIEnv * env, jclass clz) {\n")
-            write_c("\t" + struct_name + "_class = (*env)->NewGlobalRef(env, clz);\n")
-            write_c("\tCHECK(" + struct_name + "_class != NULL);\n")
-            for idx, struct_line in enumerate(field_lines):
-                if idx > 0 and idx < len(field_lines) - 3:
-                    variant = struct_line.strip().strip(",")
-                    write_c("\t" + struct_name + "_" + variant + " = (*env)->GetStaticFieldID(env, " + struct_name + "_class, \"" + variant + "\", \"Lorg/ldk/enums/" + struct_name + ";\");\n")
-                    write_c("\tCHECK(" + struct_name + "_" + variant + " != NULL);\n")
-            write_c("}\n")
-            write_c("static inline jclass " + struct_name + "_to_java(JNIEnv *env, " + struct_name + " val) {\n")
-            write_c("\tswitch (val) {\n")
-            for idx, struct_line in enumerate(field_lines):
-                if idx > 0 and idx < len(field_lines) - 3:
-                    variant = struct_line.strip().strip(",")
-                    write_c("\t\tcase " + variant + ":\n")
-                    write_c("\t\t\treturn (*env)->GetStaticObjectField(env, " + struct_name + "_class, " + struct_name + "_" + variant + ");\n")
-                    ord_v = ord_v + 1
-            write_c("\t\tdefault: abort();\n")
-            write_c("\t}\n")
-            write_c("}\n\n")
+            (c_out, native_file_out, native_out) = consts.native_c_unitary_enum_map(struct_name, [x.strip().strip(",") for x in field_lines[1:-3]])
+            write_c(c_out)
+            out_java_enum.write(native_file_out)
+            out_java.write(native_out)

 
     def map_complex_enum(struct_name, union_enum_items):
         java_hu_type = struct_name.replace("LDK", "")
         complex_enums.add(struct_name)
 
     def map_complex_enum(struct_name, union_enum_items):
         java_hu_type = struct_name.replace("LDK", "")
         complex_enums.add(struct_name)

-        with open(sys.argv[3] + "/structs/" + java_hu_type + ".java", "w") as out_java_enum:
-            out_java_enum.write(hu_struct_file_prefix)
-            out_java_enum.write("public class " + java_hu_type + " extends CommonBase {\n")
-            out_java_enum.write("\tprivate " + java_hu_type + "(Object _dummy, long ptr) { super(ptr); }\n")
-            out_java_enum.write("\t@Override @SuppressWarnings(\"deprecation\")\n")
-            out_java_enum.write("\tprotected void finalize() throws Throwable {\n")
-            out_java_enum.write("\t\tsuper.finalize();\n")
-            out_java_enum.write("\t\tif (ptr != 0) { bindings." + java_hu_type + "_free(ptr); }\n")
-            out_java_enum.write("\t}\n")
-            out_java_enum.write("\tstatic " + java_hu_type + " constr_from_ptr(long ptr) {\n")
-            out_java_enum.write("\t\tbindings." + struct_name + " raw_val = bindings." + struct_name + "_ref_from_ptr(ptr);\n")
-            java_hu_subclasses = ""
-
-            tag_field_lines = union_enum_items["field_lines"]
-            init_meth_jty_strs = {}
-            for idx, struct_line in enumerate(tag_field_lines):
-                if idx == 0:
-                    out_java.write("\tpublic static class " + struct_name + " {\n")
-                    out_java.write("\t\tprivate " + struct_name + "() {}\n")
-                elif idx == len(tag_field_lines) - 3:
-                    assert(struct_line.endswith("_Sentinel,"))
-                elif idx == len(tag_field_lines) - 2:
-                    out_java.write("\t\tstatic native void init();\n")
-                    out_java.write("\t}\n")
-                elif idx == len(tag_field_lines) - 1:
-                    assert(struct_line == "")
+
+        enum_variants = []
+        tag_field_lines = union_enum_items["field_lines"]
+        for idx, struct_line in enumerate(tag_field_lines):
+            if idx == 0:
+                assert(struct_line == "typedef enum %s_Tag {" % struct_name)
+            elif idx == len(tag_field_lines) - 3:
+                assert(struct_line.endswith("_Sentinel,"))
+            elif idx == len(tag_field_lines) - 2:
+                assert(struct_line == "} %s_Tag;" % struct_name)
+            elif idx == len(tag_field_lines) - 1:
+                assert(struct_line == "")
+            else:
+                variant_name = struct_line.strip(' ,')[len(struct_name) + 1:]
+                fields = []
+                if "LDK" + variant_name in union_enum_items:
+                    enum_var_lines = union_enum_items["LDK" + variant_name]
+                    for idx, field in enumerate(enum_var_lines):
+                        if idx != 0 and idx < len(enum_var_lines) - 2:
+                            fields.append(type_mapping_generator.map_type(field.strip(' ;'), False, None, False, True))
+                        else:
+                            # TODO: Assert line format
+                            pass

                 else:
                 else:

-                    var_name = struct_line.strip(' ,')[len(struct_name) + 1:]
-                    out_java.write("\t\tpublic final static class " + var_name + " extends " + struct_name + " {\n")
-                    java_hu_subclasses = java_hu_subclasses + "\tpublic final static class " + var_name + " extends " + java_hu_type + " {\n"
-                    out_java_enum.write("\t\tif (raw_val.getClass() == bindings." + struct_name + "." + var_name + ".class) {\n")
-                    out_java_enum.write("\t\t\treturn new " + var_name + "(ptr, (bindings." + struct_name + "." + var_name + ")raw_val);\n")
-                    write_c("static jclass " + struct_name + "_" + var_name + "_class = NULL;\n")
-                    write_c("static jmethodID " + struct_name + "_" + var_name + "_meth = NULL;\n")
-                    init_meth_jty_str = ""
-                    init_meth_params = ""
-                    init_meth_body = ""
-                    hu_conv_body = ""
-                    if "LDK" + var_name in union_enum_items:
-                        enum_var_lines = union_enum_items["LDK" + var_name]
-                        for idx, field in enumerate(enum_var_lines):
-                            if idx != 0 and idx < len(enum_var_lines) - 2:
-                                field_ty = map_type(field.strip(' ;'), False, None, False, True)
-                                out_java.write("\t\t\tpublic " + field_ty.java_ty + " " + field_ty.arg_name + ";\n")
-                                java_hu_subclasses = java_hu_subclasses + "\t\tpublic final " + field_ty.java_hu_ty + " " + field_ty.arg_name + ";\n"
-                                if field_ty.to_hu_conv is not None:
-                                    hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.java_ty + " " + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
-                                    hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.to_hu_conv.replace("\n", "\n\t\t\t") + "\n"
-                                    hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = " + field_ty.to_hu_conv_name + ";\n"
-                                else:
-                                    hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
-                                init_meth_jty_str = init_meth_jty_str + field_ty.java_fn_ty_arg
-                                if idx > 1:
-                                    init_meth_params = init_meth_params + ", "
-                                init_meth_params = init_meth_params + field_ty.java_ty + " " + field_ty.arg_name
-                                init_meth_body = init_meth_body + "this." + field_ty.arg_name + " = " + field_ty.arg_name + "; "
-                        out_java.write("\t\t\t" + var_name + "(" + init_meth_params + ") { ")
-                        out_java.write(init_meth_body)
-                        out_java.write("}\n")
-                    out_java.write("\t\t}\n")
-                    out_java_enum.write("\t\t}\n")
-                    java_hu_subclasses = java_hu_subclasses + "\t\tprivate " + var_name + "(long ptr, bindings." + struct_name + "." + var_name + " obj) {\n\t\t\tsuper(null, ptr);\n"
-                    java_hu_subclasses = java_hu_subclasses + hu_conv_body
-                    java_hu_subclasses = java_hu_subclasses + "\t\t}\n\t}\n"
-                    init_meth_jty_strs[var_name] = init_meth_jty_str
-            out_java_enum.write("\t\tassert false; return null; // Unreachable without extending the (internal) bindings interface\n\t}\n\n")
-            out_java_enum.write(java_hu_subclasses)
-            out_java.write("\tstatic { " + struct_name + ".init(); }\n")
-            out_java.write("\tpublic static native " + struct_name + " " + struct_name + "_ref_from_ptr(long ptr);\n");
-
-            write_c("JNIEXPORT void JNICALL Java_org_ldk_impl_bindings_00024" + struct_name.replace("_", "_1") + "_init (JNIEnv * env, jclass _a) {\n")
-            for idx, struct_line in enumerate(tag_field_lines):
-                if idx != 0 and idx < len(tag_field_lines) - 3:
-                    var_name = struct_line.strip(' ,')[len(struct_name) + 1:]
-                    write_c("\t" + struct_name + "_" + var_name + "_class =\n")
-                    write_c("\t\t(*env)->NewGlobalRef(env, (*env)->FindClass(env, \"Lorg/ldk/impl/bindings$" + struct_name + "$" + var_name + ";\"));\n")
-                    write_c("\tCHECK(" + struct_name + "_" + var_name + "_class != NULL);\n")
-                    write_c("\t" + struct_name + "_" + var_name + "_meth = (*env)->GetMethodID(env, " + struct_name + "_" + var_name + "_class, \"<init>\", \"(" + init_meth_jty_strs[var_name] + ")V\");\n")
-                    write_c("\tCHECK(" + struct_name + "_" + var_name + "_meth != NULL);\n")
-            write_c("}\n")
-            write_c("JNIEXPORT jobject JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1ref_1from_1ptr (JNIEnv * _env, jclass _c, jlong ptr) {\n")
-            write_c("\t" + struct_name + " *obj = (" + struct_name + "*)ptr;\n")
-            write_c("\tswitch(obj->tag) {\n")
-            for idx, struct_line in enumerate(tag_field_lines):
-                if idx != 0 and idx < len(tag_field_lines) - 3:
-                    var_name = struct_line.strip(' ,')[len(struct_name) + 1:]
-                    write_c("\t\tcase " + struct_name + "_" + var_name + ": {\n")
-                    c_params_text = ""
-                    if "LDK" + var_name in union_enum_items:
-                        enum_var_lines = union_enum_items["LDK" + var_name]
-                        for idx, field in enumerate(enum_var_lines):
-                            if idx != 0 and idx < len(enum_var_lines) - 2:
-                                field_map = map_type(field.strip(' ;'), False, None, False, True)
-                                if field_map.ret_conv is not None:
-                                    write_c("\t\t\t" + field_map.ret_conv[0].replace("\n", "\n\t\t\t"))
-                                    write_c("obj->" + camel_to_snake(var_name) + "." + field_map.arg_name)
-                                    write_c(field_map.ret_conv[1].replace("\n", "\n\t\t\t") + "\n")
-                                    c_params_text = c_params_text + ", " + field_map.ret_conv_name
-                                else:
-                                    c_params_text = c_params_text + ", obj->" + camel_to_snake(var_name) + "." + field_map.arg_name
-                    write_c("\t\t\treturn (*_env)->NewObject(_env, " + struct_name + "_" + var_name + "_class, " + struct_name + "_" + var_name + "_meth" + c_params_text + ");\n")
-                    write_c("\t\t}\n")
-            write_c("\t\tdefault: abort();\n")
-            write_c("\t}\n}\n")
-            out_java_enum.write("}\n")
+                    # TODO: Assert line format
+                    pass
+                enum_variants.append(ComplexEnumVariantInfo(variant_name, fields))
+
+        with open(f"{sys.argv[3]}/structs/{java_hu_type}{consts.file_ext}", "w") as out_java_enum:
+            (out_java_addendum, out_java_enum_addendum, out_c_addendum) = consts.map_complex_enum(struct_name, enum_variants, camel_to_snake)
+
+            out_java_enum.write(out_java_enum_addendum)
+            out_java.write(out_java_addendum)
+            write_c(out_c_addendum)

 
     def map_trait(struct_name, field_var_lines, trait_fn_lines):
 
     def map_trait(struct_name, field_var_lines, trait_fn_lines):

-        with open(sys.argv[3] + "/structs/" + struct_name.replace("LDK","") + ".java", "w") as out_java_trait:
-            write_c("typedef struct " + struct_name + "_JCalls {\n")
-            write_c("\tatomic_size_t refcnt;\n")
-            write_c("\tJavaVM *vm;\n")
-            write_c("\tjweak o;\n")
+        with open(f"{sys.argv[3]}/structs/{struct_name.replace('LDK', '')}{consts.file_ext}", "w") as out_java_trait:

             field_var_convs = []
             for var_line in field_var_lines:
                 if var_line.group(1) in trait_structs:
             field_var_convs = []
             for var_line in field_var_lines:
                 if var_line.group(1) in trait_structs:

-                    write_c("\t" + var_line.group(1) + "_JCalls* " + var_line.group(2) + ";\n")
-                    field_var_convs.append(None)
-                else:
-                    field_var_convs.append(map_type(var_line.group(1) + " " + var_line.group(2), False, None, False, False))
-            for fn_line in trait_fn_lines:
-                if fn_line.group(3) != "free" and fn_line.group(3) != "clone":
-                    write_c("\tjmethodID " + fn_line.group(3) + "_meth;\n")
-            write_c("} " + struct_name + "_JCalls;\n")
-
-            out_java_trait.write(hu_struct_file_prefix)
-            out_java_trait.write("public class " + struct_name.replace("LDK","") + " extends CommonBase {\n")
-            out_java_trait.write("\tfinal bindings." + struct_name + " bindings_instance;\n")
-            out_java_trait.write("\t" + struct_name.replace("LDK", "") + "(Object _dummy, long ptr) { super(ptr); bindings_instance = null; }\n")
-            out_java_trait.write("\tprivate " + struct_name.replace("LDK", "") + "(bindings." + struct_name + " arg")
-            for idx, var_line in enumerate(field_var_lines):
-                if var_line.group(1) in trait_structs:
-                    out_java_trait.write(", bindings." + var_line.group(1) + " " + var_line.group(2))
-                else:
-                    out_java_trait.write(", " + field_var_convs[idx].java_hu_ty + " " + var_line.group(2))
-            out_java_trait.write(") {\n")
-            out_java_trait.write("\t\tsuper(bindings." + struct_name + "_new(arg")
-            for idx, var_line in enumerate(field_var_lines):
-                if var_line.group(1) in trait_structs:
-                    out_java_trait.write(", " + var_line.group(2))
-                elif field_var_convs[idx].from_hu_conv is not None:
-                    out_java_trait.write(", " + field_var_convs[idx].from_hu_conv[0])
-                else:
-                    out_java_trait.write(", " + var_line.group(2))
-            out_java_trait.write("));\n")
-            out_java_trait.write("\t\tthis.ptrs_to.add(arg);\n")
-            for idx, var_line in enumerate(field_var_lines):
-                if var_line.group(1) in trait_structs:
-                    out_java_trait.write("\t\tthis.ptrs_to.add(" + var_line.group(2) + ");\n")
-                elif field_var_convs[idx].from_hu_conv is not None and field_var_convs[idx].from_hu_conv[1] != "":
-                    out_java_trait.write("\t\t" + field_var_convs[idx].from_hu_conv[1] + ";\n")
-            out_java_trait.write("\t\tthis.bindings_instance = arg;\n")
-            out_java_trait.write("\t}\n")
-            out_java_trait.write("\t@Override @SuppressWarnings(\"deprecation\")\n")
-            out_java_trait.write("\tprotected void finalize() throws Throwable {\n")
-            out_java_trait.write("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); } super.finalize();\n")
-            out_java_trait.write("\t}\n\n")
-
-            java_trait_constr = "\tprivate static class " + struct_name + "Holder { " + struct_name.replace("LDK", "") + " held; }\n"
-            java_trait_constr = java_trait_constr + "\tpublic static " + struct_name.replace("LDK", "") + " new_impl(" + struct_name.replace("LDK", "") + "Interface arg"
-            for idx, var_line in enumerate(field_var_lines):
-                if var_line.group(1) in trait_structs:
-                    # Ideally we'd be able to take any instance of the interface, but our C code can only represent
-                    # Java-implemented version, so we require users pass a Java implementation here :/
-                    java_trait_constr = java_trait_constr + ", " + var_line.group(1).replace("LDK", "") + "." + var_line.group(1).replace("LDK", "") + "Interface " + var_line.group(2) + "_impl"
+                    field_var_convs.append((var_line.group(1), var_line.group(2)))

                 else:
                 else:

-                    java_trait_constr = java_trait_constr + ", " + field_var_convs[idx].java_hu_ty + " " + var_line.group(2)
-            java_trait_constr = java_trait_constr + ") {\n\t\tfinal " + struct_name + "Holder impl_holder = new " + struct_name + "Holder();\n"
-            java_trait_constr = java_trait_constr + "\t\timpl_holder.held = new " + struct_name.replace("LDK", "") + "(new bindings." + struct_name + "() {\n"
-            out_java_trait.write("\tpublic static interface " + struct_name.replace("LDK", "") + "Interface {\n")
-            out_java.write("\tpublic interface " + struct_name + " {\n")
-            java_meths = []
-            for fn_line in trait_fn_lines:
-                java_meth_descr = "("
-                if fn_line.group(3) != "free" and fn_line.group(3) != "clone":
-                    ret_ty_info = map_type(fn_line.group(2), True, None, False, False)
-
-                    out_java.write("\t\t " + ret_ty_info.java_ty + " " + fn_line.group(3) + "(")
-                    java_trait_constr = java_trait_constr + "\t\t\t@Override public " + ret_ty_info.java_ty + " " + fn_line.group(3) + "("
-                    out_java_trait.write("\t\t" + ret_ty_info.java_hu_ty + " " + fn_line.group(3) + "(")
-                    is_const = fn_line.group(4) is not None
-                    write_c(fn_line.group(2) + fn_line.group(3) + "_jcall(")
-                    if is_const:
-                        write_c("const void* this_arg")
-                    else:
-                        write_c("void* this_arg")
-
-                    arg_names = []
-                    for idx, arg in enumerate(fn_line.group(5).split(',')):
-                        if arg == "":
-                            continue
-                        if idx >= 2:
-                            out_java.write(", ")
-                            java_trait_constr = java_trait_constr + ", "
-                            out_java_trait.write(", ")
-                        write_c(", ")
-                        arg_conv_info = map_type(arg, True, None, False, False)
-                        write_c(arg.strip())
-                        out_java.write(arg_conv_info.java_ty + " " + arg_conv_info.arg_name)
-                        out_java_trait.write(arg_conv_info.java_hu_ty + " " + arg_conv_info.arg_name)
-                        java_trait_constr = java_trait_constr + arg_conv_info.java_ty + " " + arg_conv_info.arg_name
-                        arg_names.append(arg_conv_info)
-                        java_meth_descr = java_meth_descr + arg_conv_info.java_fn_ty_arg
-                    java_meth_descr = java_meth_descr + ")" + ret_ty_info.java_fn_ty_arg
-                    java_meths.append((fn_line, java_meth_descr))
-
-                    out_java.write(");\n")
-                    out_java_trait.write(");\n")
-                    java_trait_constr = java_trait_constr + ") {\n"
-                    write_c(") {\n")
-                    write_c("\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n")
-                    write_c("\tJNIEnv *_env;\n")
-                    write_c("\tDO_ASSERT((*j_calls->vm)->GetEnv(j_calls->vm, (void**)&_env, JNI_VERSION_1_8) == JNI_OK);\n")
-
-                    for arg_info in arg_names:
-                        if arg_info.ret_conv is not None:
-                            write_c("\t" + arg_info.ret_conv[0].replace('\n', '\n\t'));
-                            write_c(arg_info.arg_name)
-                            write_c(arg_info.ret_conv[1].replace('\n', '\n\t') + "\n")
-                        if arg_info.to_hu_conv is not None:
-                            java_trait_constr = java_trait_constr + "\t\t\t\t" + arg_info.to_hu_conv.replace("\n", "\n\t\t\t\t") + "\n"
-
-                    write_c("\tjobject obj = (*_env)->NewLocalRef(_env, j_calls->o);\n\tCHECK(obj != NULL);\n")
-                    if ret_ty_info.c_ty.endswith("Array"):
-                        write_c("\t" + ret_ty_info.c_ty + " arg = (*_env)->CallObjectMethod(_env, obj, j_calls->" + fn_line.group(3) + "_meth")
-                    elif not ret_ty_info.passed_as_ptr:
-                        write_c("\treturn (*_env)->Call" + ret_ty_info.java_ty.title() + "Method(_env, obj, j_calls->" + fn_line.group(3) + "_meth")
-                    else:
-                        write_c("\t" + fn_line.group(2).strip() + "* ret = (" + fn_line.group(2).strip() + "*)(*_env)->CallLongMethod(_env, obj, j_calls->" + fn_line.group(3) + "_meth");
-                    if ret_ty_info.java_ty != "void":
-                        java_trait_constr = java_trait_constr + "\t\t\t\t" + ret_ty_info.java_hu_ty + " ret = arg." + fn_line.group(3) + "("
-                    else:
-                        java_trait_constr = java_trait_constr + "\t\t\t\targ." + fn_line.group(3) + "("
-
-                    for idx, arg_info in enumerate(arg_names):
-                        if arg_info.ret_conv is not None:
-                            write_c(", " + arg_info.ret_conv_name)
-                        else:
-                            write_c(", " + arg_info.arg_name)
-                        if idx != 0:
-                            java_trait_constr = java_trait_constr + ", "
-                        if arg_info.to_hu_conv_name is not None:
-                            java_trait_constr = java_trait_constr + arg_info.to_hu_conv_name
-                        else:
-                            java_trait_constr = java_trait_constr + arg_info.arg_name
-                    write_c(");\n");
-                    if ret_ty_info.arg_conv is not None:
-                        write_c("\t" + ret_ty_info.arg_conv.replace("\n", "\n\t") + "\n\treturn " + ret_ty_info.arg_conv_name + ";\n")
-
-                    write_c("}\n")
-                    java_trait_constr = java_trait_constr + ");\n"
-                    if ret_ty_info.java_ty != "void":
-                        if ret_ty_info.from_hu_conv is not None:
-                            java_trait_constr = java_trait_constr + "\t\t\t\t" + ret_ty_info.java_ty + " result = " + ret_ty_info.from_hu_conv[0] + ";\n"
-                            if ret_ty_info.from_hu_conv[1] != "":
-                                java_trait_constr = java_trait_constr + "\t\t\t\t" + ret_ty_info.from_hu_conv[1].replace("this", "impl_holder.held") + ";\n"
-                            if ret_ty_info.rust_obj in result_types:
-                                # Avoid double-free by breaking the result - we should learn to clone these and then we can be safe instead
-                                java_trait_constr = java_trait_constr + "\t\t\t\tret.ptr = 0;\n"
-                            java_trait_constr = java_trait_constr + "\t\t\t\treturn result;\n"
-                        else:
-                            java_trait_constr = java_trait_constr + "\t\t\t\treturn ret;\n"
-                    java_trait_constr = java_trait_constr + "\t\t\t}\n"
-                elif fn_line.group(3) == "free":
-                    write_c("static void " + struct_name + "_JCalls_free(void* this_arg) {\n")
-                    write_c("\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n")
-                    write_c("\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n")
-                    write_c("\t\tJNIEnv *env;\n")
-                    write_c("\t\tDO_ASSERT((*j_calls->vm)->GetEnv(j_calls->vm, (void**)&env, JNI_VERSION_1_8) == JNI_OK);\n")
-                    write_c("\t\t(*env)->DeleteWeakGlobalRef(env, j_calls->o);\n")
-                    write_c("\t\tFREE(j_calls);\n")
-                    write_c("\t}\n}\n")
-            java_trait_constr = java_trait_constr + "\t\t}"
-            for var_line in field_var_lines:
-                if var_line.group(1) in trait_structs:
-                    java_trait_constr = java_trait_constr + ", " + var_line.group(2) + ".new_impl(" + var_line.group(2) + "_impl).bindings_instance"
-                else:
-                    java_trait_constr = java_trait_constr + ", " + var_line.group(2)
-            out_java_trait.write("\t}\n")
-            out_java_trait.write(java_trait_constr + ");\n\t\treturn impl_holder.held;\n\t}\n")
-
-            # Write out a clone function whether we need one or not, as we use them in moving to rust
-            write_c("static void* " + struct_name + "_JCalls_clone(const void* this_arg) {\n")
-            write_c("\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n")
-            write_c("\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n")
-            for var_line in field_var_lines:
-                if var_line.group(1) in trait_structs:
-                    write_c("\tatomic_fetch_add_explicit(&j_calls->" + var_line.group(2) + "->refcnt, 1, memory_order_release);\n")
-            write_c("\treturn (void*) this_arg;\n")
-            write_c("}\n")
+                    field_var_convs.append(
+                        type_mapping_generator.map_type(var_line.group(1) + " " + var_line.group(2), False, None, False, False))

 
 

-            out_java.write("\t}\n")
-
-            out_java.write("\tpublic static native long " + struct_name + "_new(" + struct_name + " impl")
-            write_c("static inline " + struct_name + " " + struct_name + "_init (JNIEnv * env, jclass _a, jobject o")
-            for idx, var_line in enumerate(field_var_lines):
-                if var_line.group(1) in trait_structs:
-                    out_java.write(", " + var_line.group(1) + " " + var_line.group(2))
-                    write_c(", jobject " + var_line.group(2))
-                else:
-                    out_java.write(", " + field_var_convs[idx].java_ty + " " + var_line.group(2))
-                    write_c(", " + field_var_convs[idx].c_ty + " " + var_line.group(2))
-            out_java.write(");\n")
-            write_c(") {\n")
-
-            write_c("\tjclass c = (*env)->GetObjectClass(env, o);\n")
-            write_c("\tCHECK(c != NULL);\n")
-            write_c("\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n")
-            write_c("\tatomic_init(&calls->refcnt, 1);\n")
-            write_c("\tDO_ASSERT((*env)->GetJavaVM(env, &calls->vm) == 0);\n")
-            write_c("\tcalls->o = (*env)->NewWeakGlobalRef(env, o);\n")
-            for (fn_line, java_meth_descr) in java_meths:
-                if fn_line.group(3) != "free" and fn_line.group(3) != "clone":
-                    write_c("\tcalls->" + fn_line.group(3) + "_meth = (*env)->GetMethodID(env, c, \"" + fn_line.group(3) + "\", \"" + java_meth_descr + "\");\n")
-                    write_c("\tCHECK(calls->" + fn_line.group(3) + "_meth != NULL);\n")
-            for idx, var_line in enumerate(field_var_lines):
-                if field_var_convs[idx] is not None and field_var_convs[idx].arg_conv is not None:
-                    write_c("\n\t" + field_var_convs[idx].arg_conv.replace("\n", "\n\t") +"\n")
-            write_c("\n\t" + struct_name + " ret = {\n")
-            write_c("\t\t.this_arg = (void*) calls,\n")
+            field_fns = []

             for fn_line in trait_fn_lines:
             for fn_line in trait_fn_lines:

-                if fn_line.group(3) != "free" and fn_line.group(3) != "clone":
-                    write_c("\t\t." + fn_line.group(3) + " = " + fn_line.group(3) + "_jcall,\n")
-                elif fn_line.group(3) == "free":
-                    write_c("\t\t.free = " + struct_name + "_JCalls_free,\n")
-                else:
-                    write_c("\t\t.clone = " + struct_name + "_JCalls_clone,\n")
-            for idx, var_line in enumerate(field_var_lines):
-                if var_line.group(1) in trait_structs:
-                    write_c("\t\t." + var_line.group(2) + " = " + var_line.group(1) + "_init(env, _a, " + var_line.group(2) + "),\n")
-                elif field_var_convs[idx].arg_conv_name is not None:
-                    write_c("\t\t." + var_line.group(2) + " = " + field_var_convs[idx].arg_conv_name + ",\n")
-                    write_c("\t\t.set_" + var_line.group(2) + " = NULL,\n")
-                else:
-                    write_c("\t\t." + var_line.group(2) + " = " + var_line.group(2) + ",\n")
-                    write_c("\t\t.set_" + var_line.group(2) + " = NULL,\n")
-            write_c("\t};\n")
-            for var_line in field_var_lines:
-                if var_line.group(1) in trait_structs:
-                    write_c("\tcalls->" + var_line.group(2) + " = ret." + var_line.group(2) + ".this_arg;\n")
-            write_c("\treturn ret;\n")
-            write_c("}\n")
+                ret_ty_info = type_mapping_generator.map_type(fn_line.group(2), True, None, False, False)
+                is_const = fn_line.group(4) is not None

 
 

-            write_c("JNIEXPORT long JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1new (JNIEnv * env, jclass _a, jobject o")
-            for idx, var_line in enumerate(field_var_lines):
-                if var_line.group(1) in trait_structs:
-                    write_c(", jobject " + var_line.group(2))
-                else:
-                    write_c(", " + field_var_convs[idx].c_ty + " " + var_line.group(2))
-            write_c(") {\n")
-            write_c("\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n")
-            write_c("\t*res_ptr = " + struct_name + "_init(env, _a, o")
-            for var_line in field_var_lines:
-                write_c(", " + var_line.group(2))
-            write_c(");\n")
-            write_c("\treturn (long)res_ptr;\n")
-            write_c("}\n")
+                arg_tys = []
+                for idx, arg in enumerate(fn_line.group(5).split(',')):
+                    if arg == "":
+                        continue
+                    arg_conv_info = type_mapping_generator.map_type(arg, True, None, False, False)
+                    arg_tys.append(arg_conv_info)
+                field_fns.append(TraitMethInfo(fn_line.group(3), is_const, ret_ty_info, arg_tys))

 
 

-            out_java.write("\tpublic static native " + struct_name + " " + struct_name + "_get_obj_from_jcalls(long val);\n")
-            write_c("JNIEXPORT jobject JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1get_1obj_1from_1jcalls (JNIEnv * env, jclass _a, jlong val) {\n")
-            write_c("\tjobject ret = (*env)->NewLocalRef(env, ((" + struct_name + "_JCalls*)val)->o);\n")
-            write_c("\tCHECK(ret != NULL);\n")
-            write_c("\treturn ret;\n")
-            write_c("}\n")
+            (out_java_addendum, out_java_trait_addendum, out_c_addendum) = consts.native_c_map_trait(struct_name, field_var_convs, field_fns)
+            write_c(out_c_addendum)
+            out_java_trait.write(out_java_trait_addendum)
+            out_java.write(out_java_addendum)

 
         for fn_line in trait_fn_lines:
             # For now, just disable enabling the _call_log - we don't know how to inverse-map String
 
         for fn_line in trait_fn_lines:
             # For now, just disable enabling the _call_log - we don't know how to inverse-map String


@@ -1479,8 +636,8 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
     def map_result(struct_name, res_ty, err_ty):
         result_types.add(struct_name)
         human_ty = struct_name.replace("LDKCResult", "Result")
     def map_result(struct_name, res_ty, err_ty):
         result_types.add(struct_name)
         human_ty = struct_name.replace("LDKCResult", "Result")

-        with open(sys.argv[3] + "/structs/" + human_ty + ".java", "w") as out_java_struct:
-            out_java_struct.write(hu_struct_file_prefix)
+        with open(f"{sys.argv[3]}/structs/{human_ty}{consts.file_ext}", "w") as out_java_struct:
+            out_java_struct.write(consts.hu_struct_file_prefix)

             out_java_struct.write("public class " + human_ty + " extends CommonBase {\n")
             out_java_struct.write("\tprivate " + human_ty + "(Object _dummy, long ptr) { super(ptr); }\n")
             out_java_struct.write("\tprotected void finalize() throws Throwable {\n")
             out_java_struct.write("public class " + human_ty + " extends CommonBase {\n")
             out_java_struct.write("\tprivate " + human_ty + "(Object _dummy, long ptr) { super(ptr); }\n")
             out_java_struct.write("\tprotected void finalize() throws Throwable {\n")


@@ -1494,16 +651,21 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
             out_java_struct.write("\t\t}\n")
             out_java_struct.write("\t}\n")
 
             out_java_struct.write("\t\t}\n")
             out_java_struct.write("\t}\n")
 

-            res_map = map_type(res_ty + " res", True, None, False, True)
-            err_map = map_type(err_ty + " err", True, None, False, True)
+            res_map = type_mapping_generator.map_type(res_ty + " res", True, None, False, True)
+            err_map = type_mapping_generator.map_type(err_ty + " err", True, None, False, True)
+            can_clone = True
+            if not res_map.is_native_primitive and (res_map.rust_obj.replace("LDK", "") + "_clone" not in clone_fns):
+                can_clone = False
+            if not err_map.is_native_primitive and (err_map.rust_obj.replace("LDK", "") + "_clone" not in clone_fns):
+                can_clone = False

 
             out_java.write("\tpublic static native boolean " + struct_name + "_result_ok(long arg);\n")
 
             out_java.write("\tpublic static native boolean " + struct_name + "_result_ok(long arg);\n")

-            write_c("JNIEXPORT jboolean JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1result_1ok (JNIEnv * env, jclass _a, jlong arg) {\n")
+            write_c(consts.c_fn_ty_pfx + "jboolean " + consts.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1result_1ok (" + consts.c_fn_args_pfx + ", " + consts.ptr_c_ty + " arg) {\n")

             write_c("\treturn ((" + struct_name + "*)arg)->result_ok;\n")
             write_c("}\n")
 
             out_java.write("\tpublic static native " + res_map.java_ty + " " + struct_name + "_get_ok(long arg);\n")
             write_c("\treturn ((" + struct_name + "*)arg)->result_ok;\n")
             write_c("}\n")
 
             out_java.write("\tpublic static native " + res_map.java_ty + " " + struct_name + "_get_ok(long arg);\n")

-            write_c("JNIEXPORT " + res_map.c_ty + " JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1get_1ok (JNIEnv * _env, jclass _a, jlong arg) {\n")
+            write_c(consts.c_fn_ty_pfx + res_map.c_ty + " " + consts.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1get_1ok (" + consts.c_fn_args_pfx + ", " + consts.ptr_c_ty + " arg) {\n")

             write_c("\t" + struct_name + " *val = (" + struct_name + "*)arg;\n")
             write_c("\tCHECK(val->result_ok);\n\t")
             out_java_struct.write("\tpublic static final class " + human_ty + "_OK extends " + human_ty + " {\n")
             write_c("\t" + struct_name + " *val = (" + struct_name + "*)arg;\n")
             write_c("\tCHECK(val->result_ok);\n\t")
             out_java_struct.write("\tpublic static final class " + human_ty + "_OK extends " + human_ty + " {\n")


@@ -1540,7 +702,7 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
             out_java_struct.write("\t\t}\n\t}\n\n")
 
             out_java.write("\tpublic static native " + err_map.java_ty + " " + struct_name + "_get_err(long arg);\n")
             out_java_struct.write("\t\t}\n\t}\n\n")
 
             out_java.write("\tpublic static native " + err_map.java_ty + " " + struct_name + "_get_err(long arg);\n")

-            write_c("JNIEXPORT " + err_map.c_ty + " JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1get_1err (JNIEnv * _env, jclass _a, jlong arg) {\n")
+            write_c(consts.c_fn_ty_pfx + err_map.c_ty + " " + consts.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1get_1err (" + consts.c_fn_args_pfx + ", " + consts.ptr_c_ty + " arg) {\n")

             write_c("\t" + struct_name + " *val = (" + struct_name + "*)arg;\n")
             write_c("\tCHECK(!val->result_ok);\n\t")
             out_java_struct.write("\tpublic static final class " + human_ty + "_Err extends " + human_ty + " {\n")
             write_c("\t" + struct_name + " *val = (" + struct_name + "*)arg;\n")
             write_c("\tCHECK(!val->result_ok);\n\t")
             out_java_struct.write("\tpublic static final class " + human_ty + "_Err extends " + human_ty + " {\n")


@@ -1577,9 +739,37 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
                     out_java_struct.write("\t\t\tthis(null, bindings.C" + human_ty + "_err(err));\n")
             out_java_struct.write("\t\t}\n\t}\n}\n")
 
                     out_java_struct.write("\t\t\tthis(null, bindings.C" + human_ty + "_err(err));\n")
             out_java_struct.write("\t\t}\n\t}\n}\n")
 

+            if can_clone:
+                clone_fns.add(struct_name.replace("LDK", "") + "_clone")
+                write_c("static inline " + struct_name + " " + struct_name.replace("LDK", "") + "_clone(const " + struct_name + " *orig) {\n")
+                write_c("\t" + struct_name + " res = { .result_ok = orig->result_ok };\n")
+                write_c("\tif (orig->result_ok) {\n")
+                if res_map.c_ty == "void":
+                    write_c("\t\tres.contents.result = NULL;\n")
+                else:
+                    if res_map.is_native_primitive:
+                        write_c("\t\t" + res_map.c_ty + "* contents = MALLOC(sizeof(" + res_map.c_ty + "), \"" + res_map.c_ty + " result OK clone\");\n")
+                        write_c("\t\t*contents = *orig->contents.result;\n")
+                    else:
+                        write_c("\t\t" + res_map.rust_obj + "* contents = MALLOC(sizeof(" + res_map.rust_obj + "), \"" + res_map.rust_obj + " result OK clone\");\n")
+                        write_c("\t\t*contents = " + res_map.rust_obj.replace("LDK", "") + "_clone(orig->contents.result);\n")
+                    write_c("\t\tres.contents.result = contents;\n")
+                write_c("\t} else {\n")
+                if err_map.c_ty == "void":
+                    write_c("\t\tres.contents.err = NULL;\n")
+                else:
+                    if err_map.is_native_primitive:
+                        write_c("\t\t" + err_map.c_ty + "* contents = MALLOC(sizeof(" + err_map.c_ty + "), \"" + err_map.c_ty + " result Err clone\");\n")
+                        write_c("\t\t*contents = *orig->contents.err;\n")
+                    else:
+                        write_c("\t\t" + err_map.rust_obj + "* contents = MALLOC(sizeof(" + err_map.rust_obj + "), \"" + err_map.rust_obj + " result Err clone\");\n")
+                        write_c("\t\t*contents = " + err_map.rust_obj.replace("LDK", "") + "_clone(orig->contents.err);\n")
+                    write_c("\t\tres.contents.err = contents;\n")
+                write_c("\t}\n\treturn res;\n}\n")
+

     def map_tuple(struct_name, field_lines):
         out_java.write("\tpublic static native long " + struct_name + "_new(")
     def map_tuple(struct_name, field_lines):
         out_java.write("\tpublic static native long " + struct_name + "_new(")

-        write_c("JNIEXPORT jlong JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1new(JNIEnv *_env, jclass _b")
+        write_c(consts.c_fn_ty_pfx + consts.ptr_c_ty + " " + consts.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1new(" + consts.c_fn_args_pfx)

         ty_list = []
         for idx, line in enumerate(field_lines):
             if idx != 0 and idx < len(field_lines) - 2:
         ty_list = []
         for idx, line in enumerate(field_lines):
             if idx != 0 and idx < len(field_lines) - 2:


@@ -1594,9 +784,12 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
         out_java.write(");\n")
         write_c(") {\n")
         write_c("\t" + struct_name + "* ret = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n")
         out_java.write(");\n")
         write_c(") {\n")
         write_c("\t" + struct_name + "* ret = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n")

+        can_clone = True
+        clone_str = "static inline " + struct_name + " " + struct_name.replace("LDK", "") + "_clone(const " + struct_name + " *orig) {\n"
+        clone_str = clone_str + "\t" + struct_name + " ret = {\n"

         for idx, line in enumerate(field_lines):
             if idx != 0 and idx < len(field_lines) - 2:
         for idx, line in enumerate(field_lines):
             if idx != 0 and idx < len(field_lines) - 2:

-                ty_info = map_type(line.strip(';'), False, None, False, False)
+                ty_info = type_mapping_generator.map_type(line.strip(';'), False, None, False, False)

                 e = chr(ord('a') + idx - 1)
                 if ty_info.arg_conv is not None:
                     write_c("\t" + ty_info.arg_conv.replace("\n", "\n\t"))
                 e = chr(ord('a') + idx - 1)
                 if ty_info.arg_conv is not None:
                     write_c("\t" + ty_info.arg_conv.replace("\n", "\n\t"))


@@ -1605,15 +798,26 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
                     write_c("\tret->" + e + " = " + e + ";\n")
                 if ty_info.arg_conv_cleanup is not None:
                     write_c("\t//TODO: Really need to call " + ty_info.arg_conv_cleanup + " here\n")
                     write_c("\tret->" + e + " = " + e + ";\n")
                 if ty_info.arg_conv_cleanup is not None:
                     write_c("\t//TODO: Really need to call " + ty_info.arg_conv_cleanup + " here\n")

+                if not ty_info.is_native_primitive and (ty_info.rust_obj.replace("LDK", "") + "_clone") not in clone_fns:
+                    can_clone = False
+                elif can_clone and ty_info.is_native_primitive:
+                    clone_str = clone_str + "\t\t." + chr(ord('a') + idx - 1) + " = orig->" + chr(ord('a') + idx - 1) + ",\n"
+                elif can_clone:
+                    clone_str = clone_str + "\t\t." + chr(ord('a') + idx - 1) + " = " + ty_info.rust_obj.replace("LDK", "") + "_clone(&orig->" + chr(ord('a') + idx - 1) + "),\n"

         write_c("\treturn (long)ret;\n")
         write_c("}\n")
 
         write_c("\treturn (long)ret;\n")
         write_c("}\n")
 

+        if can_clone:
+            clone_fns.add(struct_name.replace("LDK", "") + "_clone")
+            write_c(clone_str)
+            write_c("\t};\n\treturn ret;\n}\n")
+

         for idx, ty_info in enumerate(ty_list):
             e = chr(ord('a') + idx)
             out_java.write("\tpublic static native " + ty_info.java_ty + " " + struct_name + "_get_" + e + "(long ptr);\n")
         for idx, ty_info in enumerate(ty_list):
             e = chr(ord('a') + idx)
             out_java.write("\tpublic static native " + ty_info.java_ty + " " + struct_name + "_get_" + e + "(long ptr);\n")

-            write_c("JNIEXPORT " + ty_info.c_ty + " JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1get_1" + e + "(JNIEnv *_env, jclass _b, jlong ptr) {\n")
+            write_c(consts.c_fn_ty_pfx + ty_info.c_ty + " " + consts.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1get_1" + e + "(" + consts.c_fn_args_pfx + ", " + consts.ptr_c_ty + " ptr) {\n")

             write_c("\t" + struct_name + " *tuple = (" + struct_name + "*)ptr;\n")
             write_c("\t" + struct_name + " *tuple = (" + struct_name + "*)ptr;\n")

-            conv_info = map_type_with_info(ty_info, False, None, False, True)
+            conv_info = type_mapping_generator.map_type_with_info(ty_info, False, None, False, True)

             if conv_info.ret_conv is not None:
                 write_c("\t" + conv_info.ret_conv[0].replace("\n", "\n\t") + "tuple->" + e + conv_info.ret_conv[1].replace("\n", "\n\t") + "\n")
                 write_c("\treturn " + conv_info.ret_conv_name + ";\n")
             if conv_info.ret_conv is not None:
                 write_c("\t" + conv_info.ret_conv[0].replace("\n", "\n\t") + "tuple->" + e + conv_info.ret_conv[1].replace("\n", "\n\t") + "\n")
                 write_c("\treturn " + conv_info.ret_conv_name + ";\n")


@@ -1621,138 +825,10 @@ with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java:
                 write_c("\treturn tuple->" + e + ";\n")
             write_c("}\n")
 
                 write_c("\treturn tuple->" + e + ";\n")
             write_c("}\n")
 

-    out_java.write("""package org.ldk.impl;
-import org.ldk.enums.*;
-
-public class bindings {
-       public static class VecOrSliceDef {
-               public long dataptr;
-               public long datalen;
-               public long stride;
-               public VecOrSliceDef(long dataptr, long datalen, long stride) {
-                       this.dataptr = dataptr; this.datalen = datalen; this.stride = stride;
-               }
-       }
-       static {
-               System.loadLibrary(\"lightningjni\");
-               init(java.lang.Enum.class, VecOrSliceDef.class);
-               init_class_cache();
-       }
-       static native void init(java.lang.Class c, java.lang.Class slicedef);
-       static native void init_class_cache();
-
-       public static native boolean deref_bool(long ptr);
-       public static native long deref_long(long ptr);
-       public static native void free_heap_ptr(long ptr);
-       public static native byte[] read_bytes(long ptr, long len);
-       public static native byte[] get_u8_slice_bytes(long slice_ptr);
-       public static native long bytes_to_u8_vec(byte[] bytes);
-       public static native long new_txpointer_copy_data(byte[] txdata);
-       public static native void txpointer_free(long ptr);
-       public static native byte[] txpointer_get_buffer(long ptr);
-       public static native long vec_slice_len(long vec);
-       public static native long new_empty_slice_vec();
-
-""")
-    write_c("""
-static jmethodID ordinal_meth = NULL;
-static jmethodID slicedef_meth = NULL;
-static jclass slicedef_cls = NULL;
-JNIEXPORT void Java_org_ldk_impl_bindings_init(JNIEnv * env, jclass _b, jclass enum_class, jclass slicedef_class) {
-       ordinal_meth = (*env)->GetMethodID(env, enum_class, "ordinal", "()I");
-       CHECK(ordinal_meth != NULL);
-       slicedef_meth = (*env)->GetMethodID(env, slicedef_class, "<init>", "(JJJ)V");
-       CHECK(slicedef_meth != NULL);
-       slicedef_cls = (*env)->NewGlobalRef(env, slicedef_class);
-       CHECK(slicedef_cls != NULL);
-}
-
-JNIEXPORT jboolean JNICALL Java_org_ldk_impl_bindings_deref_1bool (JNIEnv * env, jclass _a, jlong ptr) {
-       return *((bool*)ptr);
-}
-JNIEXPORT jlong JNICALL Java_org_ldk_impl_bindings_deref_1long (JNIEnv * env, jclass _a, jlong ptr) {
-       return *((long*)ptr);
-}
-JNIEXPORT void JNICALL Java_org_ldk_impl_bindings_free_1heap_1ptr (JNIEnv * env, jclass _a, jlong ptr) {
-       FREE((void*)ptr);
-}
-JNIEXPORT jbyteArray JNICALL Java_org_ldk_impl_bindings_read_1bytes (JNIEnv * _env, jclass _b, jlong ptr, jlong len) {
-       jbyteArray ret_arr = (*_env)->NewByteArray(_env, len);
-       (*_env)->SetByteArrayRegion(_env, ret_arr, 0, len, (unsigned char*)ptr);
-       return ret_arr;
-}
-JNIEXPORT jbyteArray JNICALL Java_org_ldk_impl_bindings_get_1u8_1slice_1bytes (JNIEnv * _env, jclass _b, jlong slice_ptr) {
-       LDKu8slice *slice = (LDKu8slice*)slice_ptr;
-       jbyteArray ret_arr = (*_env)->NewByteArray(_env, slice->datalen);
-       (*_env)->SetByteArrayRegion(_env, ret_arr, 0, slice->datalen, slice->data);
-       return ret_arr;
-}
-JNIEXPORT long JNICALL Java_org_ldk_impl_bindings_bytes_1to_1u8_1vec (JNIEnv * _env, jclass _b, jbyteArray bytes) {
-       LDKCVec_u8Z *vec = (LDKCVec_u8Z*)MALLOC(sizeof(LDKCVec_u8Z), "LDKCVec_u8");
-       vec->datalen = (*_env)->GetArrayLength(_env, bytes);
-       vec->data = (uint8_t*)MALLOC(vec->datalen, "LDKCVec_u8Z Bytes");
-       (*_env)->GetByteArrayRegion (_env, bytes, 0, vec->datalen, vec->data);
-       return (long)vec;
-}
-JNIEXPORT jbyteArray JNICALL Java_org_ldk_impl_bindings_txpointer_1get_1buffer (JNIEnv * env, jclass _b, jlong ptr) {
-       LDKTransaction *txdata = (LDKTransaction*)ptr;
-       LDKu8slice slice;
-       slice.data = txdata->data;
-       slice.datalen = txdata->datalen;
-       return Java_org_ldk_impl_bindings_get_1u8_1slice_1bytes(env, _b, (long)&slice);
-}
-JNIEXPORT long JNICALL Java_org_ldk_impl_bindings_new_1txpointer_1copy_1data (JNIEnv * env, jclass _b, jbyteArray bytes) {
-       LDKTransaction *txdata = (LDKTransaction*)MALLOC(sizeof(LDKTransaction), "LDKTransaction");
-       txdata->datalen = (*env)->GetArrayLength(env, bytes);
-       txdata->data = (uint8_t*)MALLOC(txdata->datalen, "Tx Data Bytes");
-       txdata->data_is_owned = false;
-       (*env)->GetByteArrayRegion (env, bytes, 0, txdata->datalen, txdata->data);
-       return (long)txdata;
-}
-JNIEXPORT void JNICALL Java_org_ldk_impl_bindings_txpointer_1free (JNIEnv * env, jclass _b, jlong ptr) {
-       LDKTransaction *tx = (LDKTransaction*)ptr;
-       tx->data_is_owned = true;
-       Transaction_free(*tx);
-       FREE((void*)ptr);
-}
-JNIEXPORT jlong JNICALL Java_org_ldk_impl_bindings_vec_1slice_1len (JNIEnv * env, jclass _a, jlong ptr) {
-       // Check offsets of a few Vec types are all consistent as we're meant to be generic across types
-       _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_SignatureZ, datalen), "Vec<*> needs to be mapped identically");
-       _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_MessageSendEventZ, datalen), "Vec<*> needs to be mapped identically");
-       _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_EventZ, datalen), "Vec<*> needs to be mapped identically");
-       _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_C2Tuple_usizeTransactionZZ, datalen), "Vec<*> needs to be mapped identically");
-       LDKCVec_u8Z *vec = (LDKCVec_u8Z*)ptr;
-       return (long)vec->datalen;
-}
-JNIEXPORT long JNICALL Java_org_ldk_impl_bindings_new_1empty_1slice_1vec (JNIEnv * _env, jclass _b) {
-       // Check sizes of a few Vec types are all consistent as we're meant to be generic across types
-       _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_SignatureZ), "Vec<*> needs to be mapped identically");
-       _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_MessageSendEventZ), "Vec<*> needs to be mapped identically");
-       _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_EventZ), "Vec<*> needs to be mapped identically");
-       _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_C2Tuple_usizeTransactionZZ), "Vec<*> needs to be mapped identically");
-       LDKCVec_u8Z *vec = (LDKCVec_u8Z*)MALLOC(sizeof(LDKCVec_u8Z), "Empty LDKCVec");
-       vec->data = NULL;
-       vec->datalen = 0;
-       return (long)vec;
-}
-
-// We assume that CVec_u8Z and u8slice are the same size and layout (and thus pointers to the two can be mixed)
-_Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKu8slice), "Vec<u8> and [u8] need to have been mapped identically");
-_Static_assert(offsetof(LDKCVec_u8Z, data) == offsetof(LDKu8slice, data), "Vec<u8> and [u8] need to have been mapped identically");
-_Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen), "Vec<u8> and [u8] need to have been mapped identically");
-
-""")
-
-    with open(sys.argv[3] + "/structs/CommonBase.java", "a") as out_java_struct:
-        out_java_struct.write("""package org.ldk.structs;
-import java.util.LinkedList;
-class CommonBase {
-       long ptr;
-       LinkedList<Object> ptrs_to = new LinkedList();
-       protected CommonBase(long ptr) { this.ptr = ptr; }
-       public long _test_only_get_ptr() { return this.ptr; }
-}
-""")
+    out_java.write(consts.bindings_header)
+
+    with open(f"{sys.argv[3]}/structs/CommonBase{consts.file_ext}", "w") as out_java_struct:
+        out_java_struct.write(consts.common_base)

 
     in_block_comment = False
     cur_block_obj = None
 
     in_block_comment = False
     cur_block_obj = None


@@ -1842,21 +918,9 @@ class CommonBase {
 
                 if is_opaque:
                     opaque_structs.add(struct_name)
 
                 if is_opaque:
                     opaque_structs.add(struct_name)

-                    with open(sys.argv[3] + "/structs/" + struct_name.replace("LDK","") + ".java", "w") as out_java_struct:
-                        out_java_struct.write(hu_struct_file_prefix)
-                        out_java_struct.write("public class " + struct_name.replace("LDK","") + " extends CommonBase")
-                        if struct_name.startswith("LDKLocked"):
-                            out_java_struct.write(" implements AutoCloseable")
-                        out_java_struct.write(" {\n")
-                        out_java_struct.write("\t" + struct_name.replace("LDK", "") + "(Object _dummy, long ptr) { super(ptr); }\n")
-                        if struct_name.startswith("LDKLocked"):
-                            out_java_struct.write("\t@Override public void close() {\n")
-                        else:
-                            out_java_struct.write("\t@Override @SuppressWarnings(\"deprecation\")\n")
-                            out_java_struct.write("\tprotected void finalize() throws Throwable {\n")
-                            out_java_struct.write("\t\tsuper.finalize();\n")
-                        out_java_struct.write("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n")
-                        out_java_struct.write("\t}\n\n")
+                    with open(f"{sys.argv[3]}/structs/{struct_name.replace('LDK', '')}{consts.file_ext}", "w") as out_java_struct:
+                        out_opaque_struct_human = consts.map_opaque_struct(struct_name)
+                        out_java_struct.write(out_opaque_struct_human)

                 elif result_contents is not None:
                     assert result_contents in result_ptr_struct_items
                     res_ty, err_ty = result_ptr_struct_items[result_contents]
                 elif result_contents is not None:
                     assert result_contents in result_ptr_struct_items
                     res_ty, err_ty = result_ptr_struct_items[result_contents]


@@ -1872,37 +936,17 @@ class CommonBase {
                 elif is_tuple:
                     map_tuple(struct_name, field_lines)
                 elif vec_ty is not None:
                 elif is_tuple:
                     map_tuple(struct_name, field_lines)
                 elif vec_ty is not None:

-                    if vec_ty in opaque_structs:
-                        out_java.write("\tpublic static native long[] " + struct_name + "_arr_info(long vec_ptr);\n")
-                        write_c("JNIEXPORT jlongArray JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1arr_1info(JNIEnv *env, jclass _b, jlong ptr) {\n")
-                    else:
-                        out_java.write("\tpublic static native VecOrSliceDef " + struct_name + "_arr_info(long vec_ptr);\n")
-                        write_c("JNIEXPORT jobject JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1arr_1info(JNIEnv *env, jclass _b, jlong ptr) {\n")
-                    write_c("\t" + struct_name + " *vec = (" + struct_name + "*)ptr;\n")
-                    if vec_ty in opaque_structs:
-                        write_c("\tjlongArray ret = (*env)->NewLongArray(env, vec->datalen);\n")
-                        write_c("\tjlong *ret_elems = (*env)->GetPrimitiveArrayCritical(env, ret, NULL);\n")
-                        write_c("\tfor (size_t i = 0; i < vec->datalen; i++) {\n")
-                        write_c("\t\tCHECK((((long)vec->data[i].inner) & 1) == 0);\n")
-                        write_c("\t\tret_elems[i] = (long)vec->data[i].inner | (vec->data[i].is_owned ? 1 : 0);\n")
-                        write_c("\t}\n")
-                        write_c("\t(*env)->ReleasePrimitiveArrayCritical(env, ret, ret_elems, 0);\n")
-                        write_c("\treturn ret;\n")
-                    else:
-                        write_c("\treturn (*env)->NewObject(env, slicedef_cls, slicedef_meth, (long)vec->data, (long)vec->datalen, sizeof(" + vec_ty + "));\n")
-                    write_c("}\n")
-
-                    ty_info = map_type(vec_ty + " arr_elem", False, None, False, False)
+                    ty_info = type_mapping_generator.map_type(vec_ty + " arr_elem", False, None, False, False)

                     if len(ty_info.java_fn_ty_arg) == 1: # ie we're a primitive of some form
                         out_java.write("\tpublic static native long " + struct_name + "_new(" + ty_info.java_ty + "[] elems);\n")
                     if len(ty_info.java_fn_ty_arg) == 1: # ie we're a primitive of some form
                         out_java.write("\tpublic static native long " + struct_name + "_new(" + ty_info.java_ty + "[] elems);\n")

-                        write_c("JNIEXPORT jlong JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1new(JNIEnv *env, jclass _b, j" + ty_info.java_ty + "Array elems){\n")
+                        write_c(consts.c_fn_ty_pfx + consts.ptr_c_ty + " " + consts.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1new(" + consts.c_fn_args_pfx + ", " + ty_info.c_ty + "Array elems) {\n")

                         write_c("\t" + struct_name + " *ret = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n")
                         write_c("\t" + struct_name + " *ret = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n")

-                        write_c("\tret->datalen = (*env)->GetArrayLength(env, elems);\n")
+                        write_c("\tret->datalen = " + consts.get_native_arr_len_call[0] + "elems" + consts.get_native_arr_len_call[1] + ";\n")

                         write_c("\tif (ret->datalen == 0) {\n")
                         write_c("\t\tret->data = NULL;\n")
                         write_c("\t} else {\n")
                         write_c("\t\tret->data = MALLOC(sizeof(" + vec_ty + ") * ret->datalen, \"" + struct_name + " Data\");\n")
                         write_c("\tif (ret->datalen == 0) {\n")
                         write_c("\t\tret->data = NULL;\n")
                         write_c("\t} else {\n")
                         write_c("\t\tret->data = MALLOC(sizeof(" + vec_ty + ") * ret->datalen, \"" + struct_name + " Data\");\n")

-                        write_c("\t\t" + ty_info.c_ty + " *java_elems = (*env)->GetPrimitiveArrayCritical(env, elems, NULL);\n")
+                        write_c("\t\t" + ty_info.c_ty + " *java_elems = " + consts.get_native_arr_ptr_call[0] + "elems" + consts.get_native_arr_ptr_call[1] + ";\n")

                         write_c("\t\tfor (size_t i = 0; i < ret->datalen; i++) {\n")
                         if ty_info.arg_conv is not None:
                             write_c("\t\t\t" + ty_info.c_ty + " arr_elem = java_elems[i];\n")
                         write_c("\t\tfor (size_t i = 0; i < ret->datalen; i++) {\n")
                         if ty_info.arg_conv is not None:
                             write_c("\t\t\t" + ty_info.c_ty + " arr_elem = java_elems[i];\n")


@@ -1912,10 +956,27 @@ class CommonBase {
                         else:
                             write_c("\t\t\tret->data[i] = java_elems[i];\n")
                         write_c("\t\t}\n")
                         else:
                             write_c("\t\t\tret->data[i] = java_elems[i];\n")
                         write_c("\t\t}\n")

-                        write_c("\t\t(*env)->ReleasePrimitiveArrayCritical(env, elems, java_elems, 0);\n")
+                        cleanup = consts.release_native_arr_ptr_call("elems", "java_elems")
+                        if cleanup is not None:
+                            write_c("\t\t" + cleanup + ";\n")

                         write_c("\t}\n")
                         write_c("\treturn (long)ret;\n")
                         write_c("}\n")
                         write_c("\t}\n")
                         write_c("\treturn (long)ret;\n")
                         write_c("}\n")

+
+                    if ty_info.is_native_primitive:
+                        clone_fns.add(struct_name.replace("LDK", "") + "_clone")
+                        write_c("static inline " + struct_name + " " + struct_name.replace("LDK", "") + "_clone(const " + struct_name + " *orig) {\n")
+                        write_c("\t" + struct_name + " ret = { .data = MALLOC(sizeof(" + ty_info.c_ty + ") * orig->datalen, \"" + struct_name + " clone bytes\"), .datalen = orig->datalen };\n")
+                        write_c("\tmemcpy(ret.data, orig->data, sizeof(" + ty_info.c_ty + ") * ret.datalen);\n")
+                        write_c("\treturn ret;\n}\n")
+                    elif (ty_info.rust_obj.replace("LDK", "") + "_clone") in clone_fns:
+                        ty_name = "CVec_" + ty_info.rust_obj.replace("LDK", "") + "Z";
+                        clone_fns.add(ty_name + "_clone")
+                        write_c("static inline " + struct_name + " " + ty_name + "_clone(const " + struct_name + " *orig) {\n")
+                        write_c("\t" + struct_name + " ret = { .data = MALLOC(sizeof(" + ty_info.rust_obj + ") * orig->datalen, \"" + struct_name + " clone bytes\"), .datalen = orig->datalen };\n")
+                        write_c("\tfor (size_t i = 0; i < ret.datalen; i++) {\n")
+                        write_c("\t\tret.data[i] = " + ty_info.rust_obj.replace("LDK", "") + "_clone(&orig->data[i]);\n")
+                        write_c("\t}\n\treturn ret;\n}\n")

                 elif is_union_enum:
                     assert(struct_name.endswith("_Tag"))
                     struct_name = struct_name[:-4]
                 elif is_union_enum:
                     assert(struct_name.endswith("_Tag"))
                     struct_name = struct_name[:-4]


@@ -1931,11 +992,16 @@ class CommonBase {
                     trait_structs.add(struct_name)
                     map_trait(struct_name, field_var_lines, trait_fn_lines)
                 elif struct_name == "LDKTxOut":
                     trait_structs.add(struct_name)
                     map_trait(struct_name, field_var_lines, trait_fn_lines)
                 elif struct_name == "LDKTxOut":

-                    with open(sys.argv[3] + "/structs/TxOut.java", "w") as out_java_struct:
-                        out_java_struct.write(hu_struct_file_prefix)
+                    with open(f"{sys.argv[3]}/structs/TxOut{consts.file_ext}", "w") as out_java_struct:
+                        out_java_struct.write(consts.hu_struct_file_prefix)

                         out_java_struct.write("public class TxOut extends CommonBase{\n")
                         out_java_struct.write("\tTxOut(java.lang.Object _dummy, long ptr) { super(ptr); }\n")
                         out_java_struct.write("\tlong to_c_ptr() { return 0; }\n")
                         out_java_struct.write("public class TxOut extends CommonBase{\n")
                         out_java_struct.write("\tTxOut(java.lang.Object _dummy, long ptr) { super(ptr); }\n")
                         out_java_struct.write("\tlong to_c_ptr() { return 0; }\n")

+                        out_java_struct.write("\t@Override @SuppressWarnings(\"deprecation\")\n")
+                        out_java_struct.write("\tprotected void finalize() throws Throwable {\n")
+                        out_java_struct.write("\t\tsuper.finalize();\n")
+                        out_java_struct.write("\t\tif (ptr != 0) { bindings.TxOut_free(ptr); }\n")
+                        out_java_struct.write("\t}\n")

                         # TODO: TxOut body
                         out_java_struct.write("}")
                 else:
                         # TODO: TxOut body
                         out_java_struct.write("}")
                 else:


@@ -1973,21 +1039,12 @@ class CommonBase {
 
     out_java.write("}\n")
     for struct_name in opaque_structs:
 
     out_java.write("}\n")
     for struct_name in opaque_structs:

-        with open(sys.argv[3] + "/structs/" + struct_name.replace("LDK","") + ".java", "a") as out_java_struct:
+        with open(f"{sys.argv[3]}/structs/{struct_name.replace('LDK', '')}{consts.file_ext}", "a") as out_java_struct:

             out_java_struct.write("}\n")
     for struct_name in trait_structs:
             out_java_struct.write("}\n")
     for struct_name in trait_structs:

-        with open(sys.argv[3] + "/structs/" + struct_name.replace("LDK","") + ".java", "a") as out_java_struct:
+        with open(f"{sys.argv[3]}/structs/{struct_name.replace('LDK', '')}{consts.file_ext}", "a") as out_java_struct:

             out_java_struct.write("}\n")
 with open(sys.argv[4], "w") as out_c:
             out_java_struct.write("}\n")
 with open(sys.argv[4], "w") as out_c:

-    out_c.write(c_file_pfx)
-    for ty in c_array_class_caches:
-        if ty + "_clz" in c_file:
-            out_c.write("static jclass " + ty + "_clz = NULL;\n")
-    out_c.write("JNIEXPORT void Java_org_ldk_impl_bindings_init_1class_1cache(JNIEnv * env, jclass _b) {\n")
-    for ty in c_array_class_caches:
-        if ty + "_clz" in c_file:
-            out_c.write("\t" + ty + "_clz = (*env)->FindClass(env, \"" + ty.replace("arr_of_", "[") + "\");\n")
-            out_c.write("\tCHECK(" + ty + "_clz != NULL);\n")
-            out_c.write("\t" + ty + "_clz = (*env)->NewGlobalRef(env, " + ty + "_clz);\n")
-    out_c.write("}\n")
+    out_c.write(consts.c_file_pfx)
+    out_c.write(consts.init_str(c_array_class_caches))

     out_c.write(c_file)
     out_c.write(c_file)