re-fix whitespace bugs
[ldk-java] / typescript_strings.py
index ad4da8409422f45cc998b287a4efb1a847e09890..a8e9acdc204a84c778eafa276892500f574ecf56 100644 (file)
@@ -20,6 +20,14 @@ class Consts:
             uint64_t = ['number'],
         )
 
+        self.wasm_decoding_map = dict(
+            int8_tArray = 'decodeArray'
+        )
+
+        self.wasm_encoding_map = dict(
+            int8_tArray = 'encodeArray',
+        )
+
         self.to_hu_conv_templates = dict(
             ptr = 'const {var_name}_hu_conv: {human_type} = new {human_type}(null, {var_name});',
             default = 'const {var_name}_hu_conv: {human_type} = new {human_type}(null, {var_name});',
@@ -63,6 +71,17 @@ public static native long new_empty_slice_vec();
 
 """
 
+        self.bindings_footer = """
+        export async function initializeWasm(allowDoubleInitialization: boolean = false): Promise<void> {
+            if(isWasmInitialized && !allowDoubleInitialization) {
+                return;
+            }
+            const wasmInstance = await WebAssembly.instantiate(wasmModule, imports)
+            wasm = wasmInstance.exports;
+            isWasmInitialized = true;
+        }
+        """
+
         self.common_base = """
             export default class CommonBase {
                 ptr: number;
@@ -76,6 +95,7 @@ public static native long new_empty_slice_vec();
 """
 
         self.c_file_pfx = """#include <rust_types.h>
+#include "js-wasm.h"
 #include <stdatomic.h>
 #include <lightning.h>
 
@@ -85,7 +105,7 @@ void *memcpy(void *dest, const void *src, size_t n);
 int memcmp(const void *s1, const void *s2, size_t n);
 
 void __attribute__((noreturn)) abort(void);
-void assert(scalar expression);
+void assert(bool expression);
 """
 
         if not DEBUG:
@@ -196,9 +216,13 @@ _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen),
 
 _Static_assert(sizeof(void*) == 4, "Pointers mut be 32 bits");
 
-typedef struct int64_tArray {uint32_t len;int64_t *ptr;} int64_tArray;
-typedef struct uint32_tArray {uint32_t len;int32_t *ptr;} uint32_tArray;
-typedef struct int8_tArray {uint32_t len;int8_t *ptr;} int8_tArray;
+typedef struct int64_tArray { uint32_t *len; /* len + 1 is data */ } int64_tArray;
+typedef struct uint32_tArray { uint32_t *len; /* len + 1 is data */ } uint32_tArray;
+typedef struct ptrArray { uint32_t *len; /* len + 1 is data */ } ptrArray;
+typedef struct int8_tArray { uint32_t *len; /* len + 1 is data */ } int8_tArray;
+typedef struct jstring {} jstring;
+
+jstring conv_owned_string(const char* _src) { jstring a; return a; }
 
 typedef bool jboolean;
 
@@ -214,64 +238,168 @@ import * as bindings from '../bindings' // TODO: figure out location
         self.c_fn_args_pfx = "void* ctx_TODO"
         self.file_ext = ".ts"
         self.ptr_c_ty = "uint32_t"
-        self.ptr_native_ty = "number" # "uint32_t"
+        self.ptr_native_ty = "number"
         self.result_c_ty = "uint32_t"
-        self.ptr_arr = "uint32_tArray"
-        self.get_native_arr_len_call = ("", ".len")
-        self.get_native_arr_ptr_call = ("", ".ptr")
+        self.owned_str_to_c_call = ("conv_owned_string(", ")")
+        self.ptr_arr = "ptrArray"
+        self.get_native_arr_len_call = ("*", ".len")
 
-    def release_native_arr_ptr_call(self, arr_var, arr_ptr_var):
+    def release_native_arr_ptr_call(self, ty_info, arr_var, arr_ptr_var):
         return None
     def create_native_arr_call(self, arr_len, ty_info):
         if ty_info.c_ty == "int8_tArray":
-            return "{ .len = " + arr_len + ", .ptr = MALLOC(" + arr_len + ", \"Native " + ty_info.c_ty + " Bytes\") }"
+            return "{ .len = MALLOC(" + arr_len + " + sizeof(uint32_t), \"Native " + ty_info.c_ty + " Bytes\") }"
         elif ty_info.c_ty == "int64_tArray":
-            return "{ .len = " + arr_len + ", .ptr = MALLOC(" + arr_len + " * sizeof(int64_t), \"Native " + ty_info.c_ty + " Bytes\") }"
+            return "{ .len = MALLOC(" + arr_len + " * sizeof(int64_t) + sizeof(uint32_t), \"Native " + ty_info.c_ty + " Bytes\") }"
         elif ty_info.c_ty == "uint32_tArray":
-            return "{ .len = " + arr_len + ", .ptr = MALLOC(" + arr_len + " * sizeof(int32_t), \"Native " + ty_info.c_ty + " Bytes\") }"
+            return "{ .len = MALLOC(" + arr_len + " * sizeof(int32_t) + sizeof(uint32_t), \"Native " + ty_info.c_ty + " Bytes\") }"
+        elif ty_info.c_ty == "ptrArray":
+            assert ty_info.subty is not None and ty_info.subty.c_ty.endswith("Array")
+            return "{ .len = MALLOC(" + arr_len + " * sizeof(int32_t) + sizeof(uint32_t), \"Native Object Bytes\") }"
         else:
             print("Need to create arr!", ty_info.c_ty)
             return ty_info.c_ty
     def set_native_arr_contents(self, arr_name, arr_len, ty_info):
         if ty_info.c_ty == "int8_tArray":
-            return ("memcpy(" + arr_name + ".ptr, ", ", " + arr_len + ")")
+            return ("memcpy(" + arr_name + ".len + 1, ", ", " + arr_len + ")")
         else:
             assert False
     def get_native_arr_contents(self, arr_name, dest_name, arr_len, ty_info, copy):
         if ty_info.c_ty == "int8_tArray":
             if copy:
-                return "memcpy(" + dest_name + ", " + arr_name + ".ptr, " + arr_len + ")"
+                return "memcpy(" + dest_name + ", " + arr_name + ".len + 1, " + arr_len + ")"
             else:
-                return arr_name + ".ptr"
+                return "(int8_t*)(" + arr_name + ".len + 1)"
         else:
-            return "(" + ty_info.subty.c_ty + "*) " + arr_name + ".ptr"
+            return "(" + ty_info.subty.c_ty + "*)(" + arr_name + ".len + 1)"
     def get_native_arr_elem(self, arr_name, idxc, ty_info):
         assert False # Only called if above is None
+    def get_native_arr_ptr_call(self, ty_info):
+        if ty_info.subty is not None:
+            return "(" + ty_info.subty.c_ty + "*)(", ".len + 1)"
+        return "(" + ty_info.c_ty + "*)(", ".len + 1)"
+    def get_native_arr_entry_call(self, ty_info, arr_name, idxc, entry_access):
+        return None
     def cleanup_native_arr_ref_contents(self, arr_name, dest_name, arr_len, ty_info):
         if ty_info.c_ty == "int8_tArray":
             return None
         else:
             return None
 
-
     def wasm_import_header(self, target):
         if target == Target.NODEJS:
             return """
-const path = require('path').join(__dirname, 'bindings.wasm');
-const bytes = require('fs').readFileSync(path);
-let imports = {};
-// add all exports to dictionary and move down?
-// use `module.exports`?
-// imports['./bindings.js'] = require('./bindings.js');
-
-const wasmModule = new WebAssembly.Module(bytes);
-const wasmInstance = new WebAssembly.Instance(wasmModule, imports);
-// module.exports = wasmInstance.exports;
-const wasm = wasmInstance.exports;
+import * as fs from 'fs';
+const source = fs.readFileSync('./ldk.wasm');
+
+const memory = new WebAssembly.Memory({initial: 256});
+const wasmModule = new WebAssembly.Module(source);
+
+const imports: any = {};
+imports.env = {};
+
+imports.env.memoryBase = 0;
+imports.env.memory = memory;
+imports.env.tableBase = 0;
+imports.env.table = new WebAssembly.Table({initial: 4, element: 'anyfunc'});
+
+imports.env["abort"] = function () {
+    console.error("ABORT");
+};
+
+let wasm = null;
+let isWasmInitialized: boolean = false;
+
+
+// WASM CODEC
+
+const nextMultipleOfFour = (value: number) => {
+    return Math.ceil(value / 4) * 4;
+}
+
+const encodeArray = (inputArray) => {
+       const cArrayPointer = wasm.wasm_malloc((inputArray.length + 1) * 4);
+       const arrayMemoryView = new Uint32Array(memory.buffer, cArrayPointer + 4, inputArray.length);
+       arrayMemoryView.set(inputArray, 1);
+    arrayMemoryView[0] = inputArray.length;
+       return cArrayPointer;
+}
+
+const getArrayLength = (arrayPointer) => {
+       const arraySizeViewer = new Uint32Array(
+               memory.buffer, // value
+               arrayPointer, // offset
+               1 // one int
+       );
+       return arraySizeViewer[0];
+}
+const decodeUint8Array = (arrayPointer, free = true) => {
+       const arraySize = getArrayLength(arrayPointer);
+       const actualArrayViewer = new Uint8Array(
+               memory.buffer, // value
+               arrayPointer + 4, // offset (ignoring length bytes)
+               arraySize // uint8 count
+       );
+       // Clone the contents, TODO: In the future we should wrap the Viewer in a class that
+       // will free the underlying memory when it becomes unreachable instead of copying here.
+       const actualArray = actualArrayViewer.slice(0, arraySize);
+       if (free) {
+               wasm.free(arrayPointer);
+       }
+       return actualArray;
+}
+const decodeUint32Array = (arrayPointer, free = true) => {
+       const arraySize = getArrayLength(arrayPointer);
+       const actualArrayViewer = new Uint32Array(
+               memory.buffer, // value
+               arrayPointer + 4, // offset (ignoring length bytes)
+               arraySize // uint32 count
+       );
+       // Clone the contents, TODO: In the future we should wrap the Viewer in a class that
+       // will free the underlying memory when it becomes unreachable instead of copying here.
+       const actualArray = actualArrayViewer.slice(0, arraySize);
+       if (free) {
+               wasm.free(arrayPointer);
+       }
+       return actualArray;
+}
+
+const encodeString = (string) => {
+    // make malloc count divisible by 4
+    const memoryNeed = nextMultipleOfFour(string.length + 1);
+    const stringPointer = wasm.wasm_malloc(memoryNeed);
+    const stringMemoryView = new Uint8Array(
+        memory.buffer, // value
+        stringPointer, // offset
+        string.length + 1 // length
+    );
+    for (let i = 0; i < string.length; i++) {
+        stringMemoryView[i] = string.charCodeAt(i);
+    }
+    stringMemoryView[string.length] = 0;
+    return stringPointer;
+}
+
+const decodeString = (stringPointer, free = true) => {
+    const memoryView = new Uint8Array(memory.buffer, stringPointer);
+    let cursor = 0;
+    let result = '';
+
+    while (memoryView[cursor] !== 0) {
+        result += String.fromCharCode(memoryView[cursor]);
+        cursor++;
+    }
+
+    if (free) {
+        wasm.wasm_free(stringPointer);
+    }
+
+    return result;
+};
 """
         return ''
 
-    def init_str(self, c_array_class_caches):
+    def init_str(self):
         return ""
 
     def native_c_unitary_enum_map(self, struct_name, variants):
@@ -478,10 +606,6 @@ const wasm = wasmInstance.exports;
         out_typescript_bindings += f"""): number {{
             throw new Error('unimplemented'); // TODO: bind to WASM
         }}
-
-        export function {struct_name}_get_obj_from_jcalls(val: number): {struct_name} {{
-            throw new Error('unimplemented'); // TODO: bind to WASM
-        }}
 """
 
         out_typescript_bindings += '\n// OUT_TYPESCRIPT_BINDINGS :: MAP_TRAIT :: END\n\n\n'
@@ -535,8 +659,10 @@ const wasm = wasmInstance.exports;
                 out_c = out_c + "\t//TODO: jobject obj = get object we can call against on j_calls->o\n"
                 if fn_line.ret_ty_info.c_ty.endswith("Array"):
                     out_c = out_c + "\t" + fn_line.ret_ty_info.c_ty + " arg; // TODO: Call " + fn_line.fn_name + " on j_calls with instance obj, returning an object"
+                elif fn_line.ret_ty_info.java_ty == "void":
+                    out_c = out_c + "\treturn; //TODO: Call " + fn_line.fn_name + " on j_calls with instance obj"
                 elif not fn_line.ret_ty_info.passed_as_ptr:
-                    out_c = out_c + "\treturn 0; //TODO: Call " + fn_line.fn_name + " on j_calls with instance obj, retruning " + fn_line.ret_ty_info.java_ty
+                    out_c = out_c + "\treturn 0; //TODO: Call " + fn_line.fn_name + " on j_calls with instance obj, returning " + fn_line.ret_ty_info.java_ty
                 else:
                     out_c = out_c + "\t" + fn_line.ret_ty_info.rust_obj + "* ret; // TODO: Call " + fn_line.fn_name + " on j_calls with instance obj, returning a pointer"
 
@@ -561,16 +687,14 @@ const wasm = wasmInstance.exports;
         out_c = out_c + "\treturn (void*) this_arg;\n"
         out_c = out_c + "}\n"
 
-        out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (" + self.c_fn_args_pfx + ", jobject o"
+        out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (" + self.c_fn_args_pfx + ", /*TODO: JS Object Reference */void* o"
         for var in field_var_conversions:
             if isinstance(var, ConvInfo):
                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
             else:
-                out_c = out_c + ", jobject " + var[1]
+                out_c = out_c + ", /*TODO: JS Object Reference */void* " + var[1]
         out_c = out_c + ") {\n"
 
-        out_c = out_c + "\tjclass c = (*env)->GetObjectClass(env, o);\n"
-        out_c = out_c + "\tCHECK(c != NULL);\n"
         out_c = out_c + "\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n"
         out_c = out_c + "\tatomic_init(&calls->refcnt, 1);\n"
         out_c = out_c + "\t//TODO: Assign calls->o from o\n"
@@ -601,7 +725,7 @@ const wasm = wasmInstance.exports;
                     out_c = out_c + "\t\t." + var.var_name + " = " + var.var_name + ",\n"
                     out_c = out_c + "\t\t.set_" + var.var_name + " = NULL,\n"
             else:
-                out_c = out_c + "\t\t." + var[1] + " = " + var[0] + "_init(env, clz, " + var[1] + "),\n"
+                out_c = out_c + "\t\t." + var[1] + " = " + var[0] + "_init(NULL, " + var[1] + "),\n"
         out_c = out_c + "\t};\n"
         for var in field_var_conversions:
             if not isinstance(var, ConvInfo):
@@ -609,15 +733,15 @@ const wasm = wasmInstance.exports;
         out_c = out_c + "\treturn ret;\n"
         out_c = out_c + "}\n"
 
-        out_c = out_c + self.c_fn_ty_pfx + "long " + self.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1new (" + self.c_fn_args_pfx + ", jobject o"
+        out_c = out_c + self.c_fn_ty_pfx + "long " + self.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1new (" + self.c_fn_args_pfx + ", /*TODO: JS Object Reference */void* o"
         for var in field_var_conversions:
             if isinstance(var, ConvInfo):
                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
             else:
-                out_c = out_c + ", jobject " + var[1]
+                out_c = out_c + ", /*TODO: JS Object Reference */ void* " + var[1]
         out_c = out_c + ") {\n"
         out_c = out_c + "\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n"
-        out_c = out_c + "\t*res_ptr = " + struct_name + "_init(env, clz, o"
+        out_c = out_c + "\t*res_ptr = " + struct_name + "_init(NULL, o"
         for var in field_var_conversions:
             if isinstance(var, ConvInfo):
                 out_c = out_c + ", " + var.arg_name
@@ -627,12 +751,6 @@ const wasm = wasmInstance.exports;
         out_c = out_c + "\treturn (long)res_ptr;\n"
         out_c = out_c + "}\n"
 
-        out_c = out_c + self.c_fn_ty_pfx + "jobject " + self.c_fn_name_pfx + struct_name.replace("_", "_1") + "_1get_1obj_1from_1jcalls (" + self.c_fn_args_pfx + ", " + self.ptr_c_ty + " val) {\n"
-        out_c = out_c + "\tjobject ret = (*env)->NewLocalRef(env, ((" + struct_name + "_JCalls*)val)->o);\n"
-        out_c = out_c + "\tCHECK(ret != NULL);\n"
-        out_c = out_c + "\treturn ret;\n"
-        out_c = out_c + "}\n"
-
         return (out_typescript_bindings, out_typescript_human, out_c)
 
     def trait_struct_inc_refcnt(self, ty_info):
@@ -744,3 +862,177 @@ const wasm = wasmInstance.exports;
                 }}
 """
         return out_opaque_struct_human
+
+    def map_function(self, argument_types, c_call_string, is_free, method_name, return_type_info, struct_meth, default_constructor_args, takes_self, args_known, has_out_java_struct: bool, type_mapping_generator):
+        out_java = ""
+        out_c = ""
+        out_java_struct = None
+
+        out_java += ("\tpublic static native ")
+        out_c += (self.c_fn_ty_pfx)
+        out_c += (return_type_info.c_ty)
+        out_java += (return_type_info.java_ty)
+        if return_type_info.ret_conv is not None:
+            ret_conv_pfx, ret_conv_sfx = return_type_info.ret_conv
+        out_java += (" " + method_name + "(")
+        out_c += (" " + self.c_fn_name_pfx + method_name.replace('_', '_1') + "(" + self.c_fn_args_pfx)
+
+        method_argument_string = ""
+        native_call_argument_string = ""
+        for idx, arg_conv_info in enumerate(argument_types):
+            if idx != 0:
+                method_argument_string += (", ")
+                native_call_argument_string += ', '
+            if arg_conv_info.c_ty != "void":
+                out_c += (", ")
+            if arg_conv_info.c_ty != "void":
+                out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
+                needs_encoding = arg_conv_info.c_ty in self.wasm_encoding_map
+                native_argument = arg_conv_info.arg_name
+                if needs_encoding:
+                    converter = self.wasm_encoding_map[arg_conv_info.c_ty]
+                    native_argument = f"{converter}({arg_conv_info.arg_name})"
+                method_argument_string += f"{arg_conv_info.arg_name}: {arg_conv_info.java_ty}"
+                native_call_argument_string += native_argument
+
+        has_return_value = return_type_info.c_ty != 'void'
+        needs_decoding = return_type_info.c_ty in self.wasm_decoding_map
+        return_statement = 'return nativeResponseValue;'
+        if not has_return_value:
+            return_statement = '// debug statements here'
+        elif needs_decoding:
+            converter = self.wasm_decoding_map[return_type_info.c_ty]
+            return_statement = f"return {converter}(nativeResponseValue);"
+
+        out_java = f"""\texport function {method_name}({method_argument_string}): {return_type_info.java_ty} {{
+               if(!isWasmInitialized) {{
+                       throw new Error("initializeWasm() must be awaited first!");
+               }}
+               const nativeResponseValue = wasm.{method_name}({native_call_argument_string});
+               {return_statement}
+       }}
+"""
+
+        if has_out_java_struct:
+            out_java_struct = ""
+            if not args_known:
+                out_java_struct += ("\t// Skipped " + method_name + "\n")
+                has_out_java_struct = False
+            else:
+                meth_n = method_name[len(struct_meth) + 1:]
+                if not takes_self:
+                    out_java_struct += (
+                            "\tpublic static " + return_type_info.java_hu_ty + " constructor_" + meth_n + "(")
+                else:
+                    out_java_struct += ("\tpublic " + return_type_info.java_hu_ty + " " + meth_n + "(")
+                for idx, arg in enumerate(argument_types):
+                    if idx != 0:
+                        if not takes_self or idx > 1:
+                            out_java_struct += (", ")
+                    elif takes_self:
+                        continue
+                    if arg.java_ty != "void":
+                        if arg.arg_name in default_constructor_args:
+                            for explode_idx, explode_arg in enumerate(default_constructor_args[arg.arg_name]):
+                                if explode_idx != 0:
+                                    out_java_struct += (", ")
+                                out_java_struct += (
+                                        explode_arg.java_hu_ty + " " + arg.arg_name + "_" + explode_arg.arg_name)
+                        else:
+                            out_java_struct += (arg.java_hu_ty + " " + arg.arg_name)
+
+        out_c += (") {\n")
+        if out_java_struct is not None:
+            out_java_struct += (") {\n")
+        for info in argument_types:
+            if info.arg_conv is not None:
+                out_c += ("\t" + info.arg_conv.replace('\n', "\n\t") + "\n")
+        if return_type_info.ret_conv is not None:
+            out_c += ("\t" + ret_conv_pfx.replace('\n', '\n\t'))
+        elif return_type_info.c_ty != "void":
+            out_c += ("\t" + return_type_info.c_ty + " ret_val = ")
+        else:
+            out_c += ("\t")
+        if c_call_string is None:
+            out_c += (method_name + "(")
+        else:
+            out_c += (c_call_string)
+        for idx, info in enumerate(argument_types):
+            if info.arg_conv_name is not None:
+                if idx != 0:
+                    out_c += (", ")
+                elif c_call_string is not None:
+                    continue
+                out_c += (info.arg_conv_name)
+        out_c += (")")
+        if return_type_info.ret_conv is not None:
+            out_c += (ret_conv_sfx.replace('\n', '\n\t'))
+        else:
+            out_c += (";")
+        for info in argument_types:
+            if info.arg_conv_cleanup is not None:
+                out_c += ("\n\t" + info.arg_conv_cleanup.replace("\n", "\n\t"))
+        if return_type_info.ret_conv is not None:
+            out_c += ("\n\treturn " + return_type_info.ret_conv_name + ";")
+        elif return_type_info.c_ty != "void":
+            out_c += ("\n\treturn ret_val;")
+        out_c += ("\n}\n\n")
+
+        if has_out_java_struct:
+            out_java_struct += ("\t\t")
+            if return_type_info.java_ty != "void":
+                out_java_struct += (return_type_info.java_ty + " ret = ")
+            out_java_struct += ("bindings." + method_name + "(")
+            for idx, info in enumerate(argument_types):
+                if idx != 0:
+                    out_java_struct += (", ")
+                if idx == 0 and takes_self:
+                    out_java_struct += ("this.ptr")
+                elif info.arg_name in default_constructor_args:
+                    out_java_struct += ("bindings." + info.java_hu_ty + "_new(")
+                    for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
+                        if explode_idx != 0:
+                            out_java_struct += (", ")
+                        expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
+                        if explode_arg.from_hu_conv is not None:
+                            out_java_struct += (
+                                explode_arg.from_hu_conv[0].replace(explode_arg.arg_name, expl_arg_name))
+                        else:
+                            out_java_struct += (expl_arg_name)
+                    out_java_struct += (")")
+                elif info.from_hu_conv is not None:
+                    out_java_struct += (info.from_hu_conv[0])
+                else:
+                    out_java_struct += (info.arg_name)
+            out_java_struct += (");\n")
+            if return_type_info.to_hu_conv is not None:
+                if not takes_self:
+                    out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t").replace("this",
+                                                                                                             return_type_info.to_hu_conv_name) + "\n")
+                else:
+                    out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t") + "\n")
+
+            for idx, info in enumerate(argument_types):
+                if idx == 0 and takes_self:
+                    pass
+                elif info.arg_name in default_constructor_args:
+                    for explode_arg in default_constructor_args[info.arg_name]:
+                        expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
+                        if explode_arg.from_hu_conv is not None and return_type_info.to_hu_conv_name:
+                            out_java_struct += ("\t\t" + explode_arg.from_hu_conv[1].replace(explode_arg.arg_name,
+                                                                                             expl_arg_name).replace(
+                                "this", return_type_info.to_hu_conv_name) + ";\n")
+                elif info.from_hu_conv is not None and info.from_hu_conv[1] != "":
+                    if not takes_self and return_type_info.to_hu_conv_name is not None:
+                        out_java_struct += (
+                                "\t\t" + info.from_hu_conv[1].replace("this", return_type_info.to_hu_conv_name) + ";\n")
+                    else:
+                        out_java_struct += ("\t\t" + info.from_hu_conv[1] + ";\n")
+
+            if return_type_info.to_hu_conv_name is not None:
+                out_java_struct += ("\t\treturn " + return_type_info.to_hu_conv_name + ";\n")
+            elif return_type_info.java_ty != "void" and return_type_info.rust_obj != "LDK" + struct_meth:
+                out_java_struct += ("\t\treturn ret;\n")
+            out_java_struct += ("\t}\n\n")
+
+        return (out_java, out_c, out_java_struct)