_ Git - ldk-java/blob - java_strings.py

   1 from bindingstypes import *
   2 from enum import Enum
   3 import sys
   4
   5 class Target(Enum):
   6     JAVA = 1,
   7     ANDROID = 2
   8     MACOS = 3
   9
  10 class Consts:
  11     def __init__(self, DEBUG: bool, target: Target, **kwargs):
  12         self.target = target
  13         self.c_array_class_caches = set()
  14         self.c_type_map = dict(
  15             bool = ['boolean'],
  16             uint8_t = ['byte'],
  17             uint16_t = ['short'],
  18             uint32_t = ['int'],
  19             uint64_t = ['long'],
  20         )
  21         self.java_type_map = dict(
  22             String = "String"
  23         )
  24         self.java_hu_type_map = dict(
  25             String = "String"
  26         )
  27
  28         self.to_hu_conv_templates = dict(
  29             ptr = '{human_type} {var_name}_hu_conv = null; if ({var_name} < 0 || {var_name} > 4096) { {var_name}_hu_conv = new {human_type}(null, {var_name}); }',
  30             default = '{human_type} {var_name}_hu_conv = null; if ({var_name} < 0 || {var_name} > 4096) { {var_name}_hu_conv = new {human_type}(null, {var_name}); }'
  31         )
  32
  33         self.bindings_header = """package org.ldk.impl;
  34 import org.ldk.enums.*;
  35 import org.ldk.impl.version;
  36 import java.io.File;
  37 import java.io.InputStream;
  38 import java.io.IOException;
  39 import java.nio.file.Files;
  40 import java.nio.file.Path;
  41 import java.nio.file.StandardCopyOption;
  42
  43 public class bindings {
  44         static {
  45                 try {
  46                         // Try to load natively first, this works on Android and in testing.
  47                         System.loadLibrary(\"lightningjni\");
  48                 } catch (UnsatisfiedLinkError system_load_err) {
  49                         // Otherwise try to load from the library jar.
  50                         File tmpdir = new File(System.getProperty("java.io.tmpdir"), "ldk-java-nativelib");
  51                         tmpdir.mkdir(); // If it fails to create, assume it was there already
  52                         tmpdir.deleteOnExit();
  53                         String libname = "liblightningjni_" + System.getProperty("os.name").replaceAll(" ", "") +
  54                                 "-" + System.getProperty("os.arch").replaceAll(" ", "") + ".nativelib";
  55                         try (InputStream is = bindings.class.getResourceAsStream("/" + libname)) {
  56                                 Path libpath = new File(tmpdir.toPath().toString(), "liblightningjni.so").toPath();
  57                                 Files.copy(is, libpath, StandardCopyOption.REPLACE_EXISTING);
  58                                 Runtime.getRuntime().load(libpath.toString());
  59                         } catch (Exception e) {
  60                                 System.err.println("Failed to load LDK native library.");
  61                                 System.err.println("System LDK native library load failed with: " + system_load_err);
  62                                 System.err.println("Resource-based LDK native library load failed with: " + e);
  63                                 throw new IllegalArgumentException(e);
  64                         }
  65                 }
  66                 init(java.lang.Enum.class);
  67                 init_class_cache();
  68                 if (!get_lib_version_string().equals(version.get_ldk_java_bindings_version()))
  69                         throw new IllegalArgumentException("Compiled LDK library and LDK class failes do not match");
  70                 // Fetching the LDK versions from C also checks that the header and binaries match
  71                 System.err.println("Loaded LDK-Java Bindings " + version.get_ldk_java_bindings_version() + " with LDK " + get_ldk_version() + " and LDK-C-Bindings " + get_ldk_c_bindings_version());
  72         }
  73         static native void init(java.lang.Class c);
  74         static native void init_class_cache();
  75         static native String get_lib_version_string();
  76
  77         public static native String get_ldk_c_bindings_version();
  78         public static native String get_ldk_version();
  79
  80 """
  81         self.bindings_version_file = """package org.ldk.impl;
  82
  83 public class version {
  84         public static String get_ldk_java_bindings_version() {
  85                 return "<git_version_ldk_garbagecollected>";
  86         }
  87 }"""
  88
  89         self.util_fn_pfx = """package org.ldk.structs;
  90 import org.ldk.impl.bindings;
  91 import org.ldk.enums.*;
  92 import org.ldk.util.*;
  93 import java.util.Arrays;
  94 import java.lang.ref.Reference;
  95 import javax.annotation.Nullable;
  96
  97 public class UtilMethods {
  98 """
  99         self.util_fn_sfx = "}"
 100         self.common_base = """package org.ldk.structs;
 101 import java.util.LinkedList;
 102 class CommonBase {
 103         long ptr;
 104         LinkedList<Object> ptrs_to = new LinkedList();
 105         protected CommonBase(long ptr) { assert ptr < 0 || ptr > 4096; this.ptr = ptr; }
 106 }
 107 """
 108
 109         self.txout_defn = """public class TxOut extends CommonBase {
 110         /** The script_pubkey in this output */
 111         public final byte[] script_pubkey;
 112         /** The value, in satoshis, of this output */
 113         public final long value;
 114
 115         TxOut(java.lang.Object _dummy, long ptr) {
 116                 super(ptr);
 117                 this.script_pubkey = bindings.TxOut_get_script_pubkey(ptr);
 118                 this.value = bindings.TxOut_get_value(ptr);
 119         }
 120         public TxOut(long value, byte[] script_pubkey) {
 121                 super(bindings.TxOut_new(script_pubkey, value));
 122                 this.script_pubkey = bindings.TxOut_get_script_pubkey(ptr);
 123                 this.value = bindings.TxOut_get_value(ptr);
 124         }
 125
 126         @Override @SuppressWarnings(\"deprecation\")
 127         protected void finalize() throws Throwable {
 128                 super.finalize();
 129                 if (ptr != 0) { bindings.TxOut_free(ptr); }
 130         }
 131 }"""
 132
 133         self.scalar_defn = """public class BigEndianScalar extends CommonBase {
 134         /** The bytes of the scalar value, in big endian */
 135         public final byte[] scalar_bytes;
 136
 137         BigEndianScalar(java.lang.Object _dummy, long ptr) {
 138                 super(ptr);
 139                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
 140         }
 141         public BigEndianScalar(byte[] scalar_bytes) {
 142                 super(bindings.BigEndianScalar_new(scalar_bytes));
 143                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
 144         }
 145
 146         @Override @SuppressWarnings(\"deprecation\")
 147         protected void finalize() throws Throwable {
 148                 super.finalize();
 149                 if (ptr != 0) { bindings.BigEndianScalar_free(ptr); }
 150         }
 151 }"""
 152
 153
 154         self.c_file_pfx = """#include <jni.h>
 155 // On OSX jlong (ie long long) is not equivalent to int64_t, so we override here
 156 #define int64_t jlong
 157 #include \"org_ldk_impl_bindings.h\"
 158 #include <lightning.h>
 159 #include <string.h>
 160 #include <stdatomic.h>
 161 #include <stdlib.h>
 162
 163 #define LIKELY(v) __builtin_expect(!!(v), 1)
 164 #define UNLIKELY(v) __builtin_expect(!!(v), 0)
 165
 166 """
 167
 168         if self.target == Target.ANDROID:
 169             self.c_file_pfx = self.c_file_pfx + """
 170 #include <android/log.h>
 171 #define DEBUG_PRINT(...) __android_log_print(ANDROID_LOG_ERROR, "LDK", __VA_ARGS__)
 172
 173 #include <unistd.h>
 174 #include <pthread.h>
 175 static void* redirect_stderr(void* ignored) {
 176         int pipes[2];
 177         pipe(pipes);
 178         dup2(pipes[1], STDERR_FILENO);
 179         char buf[8192];
 180         memset(buf, 0, 8192);
 181         ssize_t len;
 182         while ((len = read(pipes[0], buf, 8191)) > 0) {
 183                 DEBUG_PRINT("%s\\n", buf);
 184                 memset(buf, 0, 8192);
 185         }
 186         DEBUG_PRINT("End of stderr???\\n");
 187         return 0;
 188 }
 189 void __attribute__((constructor)) spawn_stderr_redirection() {
 190         pthread_t thread;
 191         pthread_create(&thread, NULL, &redirect_stderr, NULL);
 192 }
 193 """
 194         else:
 195             self.c_file_pfx = self.c_file_pfx + "#define DEBUG_PRINT(...) fprintf(stderr, __VA_ARGS__)\n"
 196
 197         if not DEBUG or self.target == Target.MACOS:
 198             self.c_file_pfx = self.c_file_pfx + """#define MALLOC(a, _) malloc(a)
 199 #define FREE(p) if ((uint64_t)(p) > 4096) { free(p); }
 200 #define CHECK_ACCESS(p)
 201 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v)
 202 """
 203         if not DEBUG:
 204             self.c_file_pfx += """#define DO_ASSERT(a) (void)(a)
 205 #define CHECK(a)
 206 """
 207         if DEBUG:
 208             self.c_file_pfx = self.c_file_pfx + """#include <assert.h>
 209 // Always run a, then assert it is true:
 210 #define DO_ASSERT(a) do { bool _assert_val = (a); assert(_assert_val); } while(0)
 211 // Assert a is true or do nothing
 212 #define CHECK(a) DO_ASSERT(a)
 213
 214 void __attribute__((constructor)) debug_log_version() {
 215         if (check_get_ldk_version() == NULL)
 216                 DEBUG_PRINT("LDK version did not match the header we built against\\n");
 217         if (check_get_ldk_bindings_version() == NULL)
 218                 DEBUG_PRINT("LDK C Bindings version did not match the header we built against\\n");
 219 }
 220 """
 221
 222             if self.target != Target.MACOS:
 223                 self.c_file_pfx += """
 224 // Running a leak check across all the allocations and frees of the JDK is a mess,
 225 // so instead we implement our own naive leak checker here, relying on the -wrap
 226 // linker option to wrap malloc/calloc/realloc/free, tracking everyhing allocated
 227 // and free'd in Rust or C across the generated bindings shared library.
 228 #include <threads.h>
 229 """
 230
 231                 if self.target == Target.ANDROID:
 232                     self.c_file_pfx = self.c_file_pfx + """
 233 #include <unwind.h>
 234 #include <dlfcn.h>
 235
 236 // Implement the execinfo functions using _Unwind_backtrace. This seems to miss many Rust
 237 // symbols, so we only use it on Android, where execinfo.h is unavailable.
 238
 239 struct BacktraceState {
 240         void** current;
 241         void** end;
 242 };
 243 static _Unwind_Reason_Code unwind_callback(struct _Unwind_Context* context, void* arg) {
 244         struct BacktraceState* state = (struct BacktraceState*)arg;
 245         uintptr_t pc = _Unwind_GetIP(context);
 246         if (pc) {
 247                 if (state->current == state->end) {
 248                         return _URC_END_OF_STACK;
 249                 } else {
 250                         *state->current++ = (void*)(pc);
 251                 }
 252         }
 253         return _URC_NO_REASON;
 254 }
 255
 256 int backtrace(void** buffer, int max) {
 257         struct BacktraceState state = { buffer, buffer + max };
 258         _Unwind_Backtrace(unwind_callback, &state);
 259         return state.current - buffer;
 260 }
 261
 262 void backtrace_symbols_fd(void ** buffer, int count, int _fd) {
 263         for (int idx = 0; idx < count; ++idx) {
 264                 Dl_info info;
 265                 if (dladdr(buffer[idx], &info) && info.dli_sname) {
 266                         DEBUG_PRINT("%p: %s", buffer[idx], info.dli_sname);
 267                 } else {
 268                         DEBUG_PRINT("%p: ???", buffer[idx]);
 269                 }
 270         }
 271 }
 272 """
 273                 else:
 274                     self.c_file_pfx = self.c_file_pfx + "#include <execinfo.h>\n"
 275                 self.c_file_pfx = self.c_file_pfx + """
 276 #include <unistd.h>
 277 #include <pthread.h>
 278 static pthread_mutex_t allocation_mtx;
 279
 280 void __attribute__((constructor)) init_mtx() {
 281         DO_ASSERT(!pthread_mutex_init(&allocation_mtx, NULL));
 282 }
 283
 284 #define BT_MAX 128
 285 typedef struct allocation {
 286         struct allocation* next;
 287         void* ptr;
 288         const char* struct_name;
 289         void* bt[BT_MAX];
 290         int bt_len;
 291         unsigned long alloc_len;
 292 } allocation;
 293 static allocation* allocation_ll = NULL;
 294
 295 void* __real_malloc(size_t len);
 296 void* __real_calloc(size_t nmemb, size_t len);
 297 static void new_allocation(void* res, const char* struct_name, size_t len) {
 298         allocation* new_alloc = __real_malloc(sizeof(allocation));
 299         new_alloc->ptr = res;
 300         new_alloc->struct_name = struct_name;
 301         new_alloc->bt_len = backtrace(new_alloc->bt, BT_MAX);
 302         new_alloc->alloc_len = len;
 303         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 304         new_alloc->next = allocation_ll;
 305         allocation_ll = new_alloc;
 306         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 307 }
 308 static void* MALLOC(size_t len, const char* struct_name) {
 309         void* res = __real_malloc(len);
 310         new_allocation(res, struct_name, len);
 311         return res;
 312 }
 313 void __real_free(void* ptr);
 314 static void alloc_freed(void* ptr) {
 315         allocation* p = NULL;
 316         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 317         allocation* it = allocation_ll;
 318         while (it->ptr != ptr) {
 319                 p = it; it = it->next;
 320                 if (it == NULL) {
 321                         DEBUG_PRINT("ERROR: Tried to free unknown pointer %p at:\\n", ptr);
 322                         void* bt[BT_MAX];
 323                         int bt_len = backtrace(bt, BT_MAX);
 324                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 325                         DEBUG_PRINT("\\n\\n");
 326                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 327                         return; // addrsan should catch malloc-unknown and print more info than we have
 328                 }
 329         }
 330         if (p) { p->next = it->next; } else { allocation_ll = it->next; }
 331         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 332         DO_ASSERT(it->ptr == ptr);
 333         __real_free(it);
 334 }
 335 static void FREE(void* ptr) {
 336         if ((uint64_t)ptr <= 4096) return; // Rust loves to create pointers to the NULL page for dummys
 337         alloc_freed(ptr);
 338         __real_free(ptr);
 339 }
 340
 341 void* __wrap_malloc(size_t len) {
 342         void* res = __real_malloc(len);
 343         new_allocation(res, "malloc call", len);
 344         return res;
 345 }
 346 void* __wrap_calloc(size_t nmemb, size_t len) {
 347         void* res = __real_calloc(nmemb, len);
 348         new_allocation(res, "calloc call", len);
 349         return res;
 350 }
 351 void __wrap_free(void* ptr) {
 352         if (ptr == NULL) return;
 353         alloc_freed(ptr);
 354         __real_free(ptr);
 355 }
 356
 357 static void CHECK_ACCESS(const void* ptr) {
 358         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 359         allocation* it = allocation_ll;
 360         while (it->ptr != ptr) {
 361                 it = it->next;
 362                 if (it == NULL) {
 363                         DEBUG_PRINT("ERROR: Tried to access unknown pointer %p at:\\n", ptr);
 364                         void* bt[BT_MAX];
 365                         int bt_len = backtrace(bt, BT_MAX);
 366                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 367                         DEBUG_PRINT("\\n\\n");
 368                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 369                         return; // addrsan should catch and print more info than we have
 370                 }
 371         }
 372         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 373 }
 374 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v) \\
 375         if (v.is_owned && v.inner != NULL) { \\
 376                 const void *p = __unmangle_inner_ptr(v.inner); \\
 377                 if (p != NULL) { \\
 378                         CHECK_ACCESS(p); \\
 379                 } \\
 380         }
 381
 382 void* __real_realloc(void* ptr, size_t newlen);
 383 void* __wrap_realloc(void* ptr, size_t len) {
 384         if (ptr != NULL) alloc_freed(ptr);
 385         void* res = __real_realloc(ptr, len);
 386         new_allocation(res, "realloc call", len);
 387         return res;
 388 }
 389 void __wrap_reallocarray(void* ptr, size_t new_sz) {
 390         // Rust doesn't seem to use reallocarray currently
 391         DO_ASSERT(false);
 392 }
 393
 394 void __attribute__((destructor)) check_leaks() {
 395         unsigned long alloc_count = 0;
 396         unsigned long alloc_size = 0;
 397         DEBUG_PRINT("The following LDK-allocated blocks still remain.\\n");
 398         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
 399         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 400         for (allocation* a = allocation_ll; a != NULL; a = a->next) {
 401                 DEBUG_PRINT("%s %p (%lu bytes) remains:\\n", a->struct_name, a->ptr, a->alloc_len);
 402                 backtrace_symbols_fd(a->bt, a->bt_len, STDERR_FILENO);
 403                 DEBUG_PRINT("\\n\\n");
 404                 alloc_count++;
 405                 alloc_size += a->alloc_len;
 406         }
 407         DEBUG_PRINT("%lu allocations remained for %lu bytes.\\n", alloc_count, alloc_size);
 408         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
 409         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 410 }
 411 """
 412         self.c_file_pfx = self.c_file_pfx + """
 413 static jmethodID ordinal_meth = NULL;
 414 JNIEXPORT void Java_org_ldk_impl_bindings_init(JNIEnv * env, jclass _b, jclass enum_class) {
 415         ordinal_meth = (*env)->GetMethodID(env, enum_class, "ordinal", "()I");
 416         CHECK(ordinal_meth != NULL);
 417 }
 418
 419 // We assume that CVec_u8Z and u8slice are the same size and layout (and thus pointers to the two can be mixed)
 420 _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKu8slice), "Vec<u8> and [u8] need to have been mapped identically");
 421 _Static_assert(offsetof(LDKCVec_u8Z, data) == offsetof(LDKu8slice, data), "Vec<u8> and [u8] need to have been mapped identically");
 422 _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen), "Vec<u8> and [u8] need to have been mapped identically");
 423
 424 _Static_assert(sizeof(jlong) == sizeof(int64_t), "We assume that j-types are the same as C types");
 425 _Static_assert(sizeof(jbyte) == sizeof(char), "We assume that j-types are the same as C types");
 426 _Static_assert(sizeof(void*) <= 8, "Pointers must fit into 64 bits");
 427
 428 typedef jlongArray int64_tArray;
 429 typedef jbyteArray int8_tArray;
 430 typedef jshortArray int16_tArray;
 431
 432 static inline jstring str_ref_to_java(JNIEnv *env, const char* chars, size_t len) {
 433         // Sadly we need to create a temporary because Java can't accept a char* without a 0-terminator
 434         char* conv_buf = MALLOC(len + 1, "str conv buf");
 435         memcpy(conv_buf, chars, len);
 436         conv_buf[len] = 0;
 437         jstring ret = (*env)->NewStringUTF(env, conv_buf);
 438         FREE(conv_buf);
 439         return ret;
 440 }
 441 static inline LDKStr java_to_owned_str(JNIEnv *env, jstring str) {
 442         uint64_t str_len = (*env)->GetStringUTFLength(env, str);
 443         char* newchars = MALLOC(str_len + 1, "String chars");
 444         const char* jchars = (*env)->GetStringUTFChars(env, str, NULL);
 445         memcpy(newchars, jchars, str_len);
 446         newchars[str_len] = 0;
 447         (*env)->ReleaseStringUTFChars(env, str, jchars);
 448         LDKStr res = {
 449                 .chars = newchars,
 450                 .len = str_len,
 451                 .chars_is_owned = true
 452         };
 453         return res;
 454 }
 455
 456 JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1ldk_1c_1bindings_1version(JNIEnv *env, jclass _c) {
 457         return str_ref_to_java(env, check_get_ldk_bindings_version(), strlen(check_get_ldk_bindings_version()));
 458 }
 459 JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1ldk_1version(JNIEnv *env, jclass _c) {
 460         return str_ref_to_java(env, check_get_ldk_version(), strlen(check_get_ldk_version()));
 461 }
 462 #include "version.c"
 463 """
 464         self.c_version_file = """JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1lib_1version_1string(JNIEnv *env, jclass _c) {
 465         return str_ref_to_java(env, "<git_version_ldk_garbagecollected>", strlen("<git_version_ldk_garbagecollected>"));
 466 }"""
 467
 468         self.hu_struct_file_prefix = """package org.ldk.structs;
 469
 470 import org.ldk.impl.bindings;
 471 import org.ldk.enums.*;
 472 import org.ldk.util.*;
 473 import java.util.Arrays;
 474 import java.lang.ref.Reference;
 475 import javax.annotation.Nullable;
 476
 477 """
 478         self.hu_struct_file_suffix = ""
 479         self.c_fn_ty_pfx = "JNIEXPORT "
 480         self.c_fn_args_pfx = "JNIEnv *env, jclass clz"
 481         self.file_ext = ".java"
 482         self.ptr_c_ty = "int64_t"
 483         self.ptr_native_ty = "long"
 484         self.u128_native_ty = "UInt128"
 485         self.usize_c_ty = "int64_t"
 486         self.usize_native_ty = "long"
 487         self.native_zero_ptr = "0"
 488         self.result_c_ty = "jclass"
 489         self.ptr_arr = "jobjectArray"
 490         self.is_arr_some_check = ("", " != NULL")
 491         self.get_native_arr_len_call = ("(*env)->GetArrayLength(env, ", ")")
 492
 493     def bindings_footer(self):
 494         return "}\n"
 495
 496     def construct_jenv(self):
 497         res =  "JNIEnv *env;\n"
 498         res += "jint get_jenv_res = (*j_calls->vm)->GetEnv(j_calls->vm, (void**)&env, JNI_VERSION_1_6);\n"
 499         res += "if (get_jenv_res == JNI_EDETACHED) {\n"
 500         if self.target == Target.ANDROID:
 501             res += "\tDO_ASSERT((*j_calls->vm)->AttachCurrentThread(j_calls->vm, &env, NULL) == JNI_OK);\n"
 502         else:
 503             res += "\tDO_ASSERT((*j_calls->vm)->AttachCurrentThread(j_calls->vm, (void**)&env, NULL) == JNI_OK);\n"
 504         res += "} else {\n"
 505         res += "\tDO_ASSERT(get_jenv_res == JNI_OK);\n"
 506         res += "}\n"
 507         return res
 508     def deconstruct_jenv(self):
 509         res = "if (get_jenv_res == JNI_EDETACHED) {\n"
 510         res += "\tDO_ASSERT((*j_calls->vm)->DetachCurrentThread(j_calls->vm) == JNI_OK);\n"
 511         res += "}\n"
 512         return res
 513
 514     def release_native_arr_ptr_call(self, ty_info, arr_var, arr_ptr_var):
 515         if ty_info.subty is None or not ty_info.subty.c_ty.endswith("Array"):
 516             return "(*env)->ReleasePrimitiveArrayCritical(env, " + arr_var + ", " + arr_ptr_var + ", 0)"
 517         return None
 518     def create_native_arr_call(self, arr_len, ty_info):
 519         if ty_info.c_ty == "int8_tArray":
 520             return "(*env)->NewByteArray(env, " + arr_len + ")"
 521         elif ty_info.subty.c_ty.endswith("Array"):
 522             clz_var = ty_info.java_fn_ty_arg[1:].replace("[", "arr_of_")
 523             self.c_array_class_caches.add(clz_var)
 524             return "(*env)->NewObjectArray(env, " + arr_len + ", " + clz_var + "_clz, NULL);\n"
 525         elif ty_info.subty.c_ty == "jstring":
 526             return "(*env)->NewObjectArray(env, " + arr_len + ", String_clz, NULL);\n"
 527         else:
 528             return "(*env)->New" + ty_info.java_ty.strip("[]").title() + "Array(env, " + arr_len + ")"
 529     def set_native_arr_contents(self, arr_name, arr_len, ty_info):
 530         if ty_info.c_ty == "int8_tArray":
 531             return ("(*env)->SetByteArrayRegion(env, " + arr_name + ", 0, " + arr_len + ", ", ")")
 532         elif ty_info.c_ty == "int16_tArray":
 533             return ("(*env)->SetShortArrayRegion(env, " + arr_name + ", 0, " + arr_len + ", ", ")")
 534         else:
 535             assert False
 536     def get_native_arr_contents(self, arr_name, dest_name, arr_len, ty_info, copy):
 537         if "String" in ty_info.java_ty:
 538             return None
 539         if ty_info.c_ty == "int8_tArray" or ty_info.c_ty == "int16_tArray":
 540             fn_ty = "Byte" if ty_info.c_ty == "int8_tArray" else "Short"
 541             if copy:
 542                 return "(*env)->Get" + fn_ty + "ArrayRegion(env, " + arr_name + ", 0, " + arr_len + ", " + dest_name + ")"
 543             else:
 544                 return "(*env)->Get" + fn_ty + "ArrayElements (env, " + arr_name + ", NULL)"
 545         elif not ty_info.java_ty[:len(ty_info.java_ty) - 2].endswith("[]"):
 546             return "(*env)->Get" + ty_info.subty.java_ty.title() + "ArrayElements (env, " + arr_name + ", NULL)"
 547         else:
 548             return None
 549     def get_native_arr_elem(self, arr_name, idxc, ty_info):
 550         if self.get_native_arr_contents(arr_name, "", "", ty_info, False) is None:
 551             return "(*env)->GetObjectArrayElement(env, " + arr_name + ", " + idxc + ")"
 552         else:
 553             assert False # Only called if above is None
 554     def get_native_arr_ptr_call(self, ty_info):
 555         if ty_info.subty is not None and ty_info.subty.c_ty.endswith("Array"):
 556             return None
 557         return ("(*env)->GetPrimitiveArrayCritical(env, ", ", NULL)")
 558     def get_native_arr_entry_call(self, ty_info, arr_name, idxc, entry_access):
 559         if ty_info.subty is None or not ty_info.subty.c_ty.endswith("Array"):
 560             return None
 561         return "(*env)->SetObjectArrayElement(env, " + arr_name + ", " + idxc + ", " + entry_access + ")"
 562     def cleanup_native_arr_ref_contents(self, arr_name, dest_name, arr_len, ty_info):
 563         if ty_info.c_ty == "int8_tArray":
 564             return "(*env)->ReleaseByteArrayElements(env, " + arr_name + ", (int8_t*)" + dest_name + ", 0);"
 565         else:
 566             return "(*env)->Release" + ty_info.java_ty.strip("[]").title() + "ArrayElements(env, " + arr_name + ", " + dest_name + ", 0)"
 567
 568     def map_hu_array_elems(self, arr_name, conv_name, arr_ty, elem_ty):
 569         if elem_ty.java_ty == "long" and elem_ty.java_hu_ty != "long":
 570             return arr_name + " != null ? Arrays.stream(" + arr_name + ").mapToLong(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray() : null"
 571         elif elem_ty.java_ty == "long":
 572             return arr_name + " != null ? Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray() : null"
 573         elif elem_ty.java_hu_ty == "UInt5":
 574             return arr_name + " != null ? InternalUtils.convUInt5Array(" + arr_name + ") : null"
 575         elif elem_ty.java_hu_ty == "WitnessVersion":
 576             return arr_name + " != null ? InternalUtils.convWitnessVersionArray(" + arr_name + ") : null"
 577         else:
 578             return arr_name + " != null ? Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray(" + arr_ty.java_ty + "::new) : null"
 579
 580     def str_ref_to_native_call(self, var_name, str_len):
 581         return "str_ref_to_java(env, " + var_name + ", " + str_len + ")"
 582     def str_ref_to_c_call(self, var_name):
 583         return "java_to_owned_str(env, " + var_name + ")"
 584     def str_to_hu_conv(self, var_name):
 585         return None
 586     def str_from_hu_conv(self, var_name):
 587         return None
 588
 589     def c_fn_name_define_pfx(self, fn_name, has_args):
 590         if has_args:
 591             return "JNICALL Java_org_ldk_impl_bindings_" + fn_name.replace("_", "_1") + "(JNIEnv *env, jclass clz, "
 592         return "JNICALL Java_org_ldk_impl_bindings_" + fn_name.replace("_", "_1") + "(JNIEnv *env, jclass clz"
 593
 594     def init_str(self):
 595         res = ""
 596         for ty in sorted(self.c_array_class_caches):
 597             res = res + "static jclass " + ty + "_clz = NULL;\n"
 598         res = res + "static jclass String_clz = NULL;\n"
 599         res = res + "JNIEXPORT void Java_org_ldk_impl_bindings_init_1class_1cache(JNIEnv * env, jclass clz) {\n"
 600         for ty in sorted(self.c_array_class_caches):
 601             res = res + "\t" + ty + "_clz = (*env)->FindClass(env, \"" + ty.replace("arr_of_", "[") + "\");\n"
 602             res = res + "\tCHECK(" + ty + "_clz != NULL);\n"
 603             res = res + "\t" + ty + "_clz = (*env)->NewGlobalRef(env, " + ty + "_clz);\n"
 604         res = res + "\tString_clz = (*env)->FindClass(env, \"java/lang/String\");\n"
 605         res = res + "\tCHECK(String_clz != NULL);\n"
 606         res = res + "\tString_clz = (*env)->NewGlobalRef(env, String_clz);\n"
 607
 608         res = res + "}\n"
 609         return res
 610
 611     def var_decl_statement(self, ty_string, var_name, statement):
 612         return ty_string + " " + var_name + " = " + statement
 613
 614     def get_java_arr_len(self, arr_name):
 615         return arr_name + ".length"
 616     def get_java_arr_elem(self, elem_ty, arr_name, idx):
 617         return arr_name + "[" + idx + "]"
 618     def constr_hu_array(self, ty_info, arr_len):
 619         base_ty = ty_info.subty.java_hu_ty.split("[")[0].split("<")[0]
 620         conv = "new " + base_ty + "[" + arr_len + "]"
 621         if "[" in ty_info.subty.java_hu_ty.split("<")[0]:
 622             # Do a bit of a dance to move any excess [] to the end
 623             conv += "[" + ty_info.subty.java_hu_ty.split("<")[0].split("[")[1]
 624         return conv
 625     def cleanup_converted_native_array(self, ty_info, arr_name):
 626         return None
 627
 628     def primitive_arr_from_hu(self, arr_ty, fixed_len, arr_name):
 629         mapped_ty = arr_ty.subty
 630         if arr_ty.rust_obj == "LDKU128":
 631             return ("" + arr_name + ".getLEBytes()", "")
 632         if fixed_len is not None:
 633             if mapped_ty.c_ty == "int8_t" or mapped_ty.c_ty == "uint8_t":
 634                 return ("InternalUtils.check_arr_len(" + arr_name + ", " + fixed_len + ")", "")
 635             elif mapped_ty.c_ty == "int16_t" or mapped_ty.c_ty == "uint16_t":
 636                 return ("InternalUtils.check_arr_16_len(" + arr_name + ", " + fixed_len + ")", "")
 637             else:
 638                 print(arr_ty.c_ty)
 639                 assert False
 640         return None
 641     def primitive_arr_to_hu(self, arr_ty, fixed_len, arr_name, conv_name):
 642         if arr_ty.rust_obj == "LDKU128":
 643             return "org.ldk.util.UInt128 " + conv_name + " = new org.ldk.util.UInt128(" + arr_name + ");"
 644         return None
 645
 646     def java_arr_ty_str(self, elem_ty_str):
 647         return elem_ty_str + "[]"
 648
 649     def for_n_in_range(self, n, minimum, maximum):
 650         return "for (int " + n + " = " + minimum + "; " + n + " < " + maximum + "; " + n + "++) {"
 651     def for_n_in_arr(self, n, arr_name, arr_elem_ty):
 652         return ("for (" + arr_elem_ty.java_hu_ty + " " + n + ": " + arr_name + ") { ", " }")
 653
 654     def get_ptr(self, var):
 655         return var + ".ptr"
 656     def set_null_skip_free(self, var):
 657         return var + ".ptr" + " = 0;"
 658
 659     def add_ref(self, holder, referent):
 660         return "if (" + holder + " != null) { " + holder + ".ptrs_to.add(" + referent + "); }"
 661
 662     def fully_qualified_hu_ty_path(self, ty):
 663         if ty.java_fn_ty_arg.startswith("L") and ty.java_fn_ty_arg.endswith(";"):
 664             return ty.java_fn_ty_arg.strip("L;").replace("/", ".")
 665         if ty.java_hu_ty == "UnqualifiedError" or ty.java_hu_ty == "UInt128" or ty.java_hu_ty == "UInt5" or ty.java_hu_ty == "WitnessVersion":
 666             return "org.ldk.util." + ty.java_hu_ty
 667         if not ty.is_native_primitive and ty.rust_obj is not None and not "[]" in ty.java_hu_ty:
 668             return "org.ldk.structs." + ty.java_hu_ty
 669         return ty.java_hu_ty
 670
 671     def native_c_unitary_enum_map(self, struct_name, variants, enum_doc_comment):
 672         out_java_enum = "package org.ldk.enums;\n\n"
 673         out_java = ""
 674         out_c = ""
 675         out_c += "static inline LDK" + struct_name + " LDK" + struct_name + "_from_java(" + self.c_fn_args_pfx + ") {\n"
 676         out_c += "\tjint ord = (*env)->CallIntMethod(env, clz, ordinal_meth);\n"
 677         out_c += "\tif (UNLIKELY((*env)->ExceptionCheck(env))) {\n"
 678         out_c += "\t\t(*env)->ExceptionDescribe(env);\n"
 679         out_c += "\t\t(*env)->FatalError(env, \"A call to " + struct_name + ".ordinal() from rust threw an exception.\");\n"
 680         out_c += "\t}\n"
 681         out_c += "\tswitch (ord) {\n"
 682
 683         if enum_doc_comment is not None:
 684             out_java_enum += "/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
 685         out_java_enum += "public enum " + struct_name + " {\n"
 686         ord_v = 0
 687         for var, var_docs in variants:
 688             if var_docs is not None:
 689                 out_java_enum += "\t/**\n\t * " + var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
 690             out_java_enum += "\t" + var + ",\n"
 691             out_c = out_c + "\t\tcase %d: return %s;\n" % (ord_v, var)
 692             ord_v = ord_v + 1
 693         out_java_enum = out_java_enum + "\t; static native void init();\n"
 694         out_java_enum = out_java_enum + "\tstatic { init(); }\n"
 695         out_java_enum = out_java_enum + "}"
 696         out_java = out_java + "\tstatic { " + struct_name + ".values(); /* Force enum statics to run */ }\n"
 697         out_c += "\t}\n"
 698         out_c += "\t(*env)->FatalError(env, \"A call to " + struct_name + ".ordinal() from rust returned an invalid value.\");\n"
 699         out_c += "\tabort(); // Unreachable, but will let the compiler know we don't return here\n"
 700         out_c += "}\n"
 701
 702         out_c = out_c + "static jclass " + struct_name + "_class = NULL;\n"
 703         for var, _ in variants:
 704             out_c = out_c + "static jfieldID " + struct_name + "_" + var + " = NULL;\n"
 705         out_c = out_c + self.c_fn_ty_pfx + "void JNICALL Java_org_ldk_enums_" + struct_name.replace("_", "_1") + "_init (" + self.c_fn_args_pfx + ") {\n"
 706         out_c = out_c + "\t" + struct_name + "_class = (*env)->NewGlobalRef(env, clz);\n"
 707         out_c = out_c + "\tCHECK(" + struct_name + "_class != NULL);\n"
 708         for var, _ in variants:
 709             out_c = out_c + "\t" + struct_name + "_" + var + " = (*env)->GetStaticFieldID(env, " + struct_name + "_class, \"" + var + "\", \"Lorg/ldk/enums/" + struct_name + ";\");\n"
 710             out_c = out_c + "\tCHECK(" + struct_name + "_" + var + " != NULL);\n"
 711         out_c = out_c + "}\n"
 712         out_c = out_c + "static inline jclass LDK" + struct_name + "_to_java(JNIEnv *env, LDK" + struct_name + " val) {\n"
 713         out_c = out_c + "\tswitch (val) {\n"
 714         ord_v = 0
 715         for var, _ in variants:
 716             out_c = out_c + "\t\tcase " + var + ":\n"
 717             out_c = out_c + "\t\t\treturn (*env)->GetStaticObjectField(env, " + struct_name + "_class, " + struct_name + "_" + var + ");\n"
 718             ord_v = ord_v + 1
 719         out_c = out_c + "\t\tdefault: abort();\n"
 720         out_c = out_c + "\t}\n"
 721         out_c = out_c + "}\n\n"
 722
 723         return (out_c, out_java_enum, out_java)
 724
 725     def c_unitary_enum_to_native_call(self, ty_info):
 726         return (ty_info.rust_obj + "_to_java(env, ", ")")
 727     def native_unitary_enum_to_c_call(self, ty_info):
 728         return (ty_info.rust_obj + "_from_java(env, ", ")")
 729
 730     def c_complex_enum_pfx(self, struct_name, variants, init_meth_jty_strs):
 731         out_c = ""
 732         for var in variants:
 733             out_c = out_c + "static jclass " + struct_name + "_" + var + "_class = NULL;\n"
 734             out_c = out_c + "static jmethodID " + struct_name + "_" + var + "_meth = NULL;\n"
 735         out_c = out_c + self.c_fn_ty_pfx + "void JNICALL Java_org_ldk_impl_bindings_00024" + struct_name.replace("_", "_1") + "_init (" + self.c_fn_args_pfx + ") {\n"
 736         for var_name in variants:
 737             out_c += "\t" + struct_name + "_" + var_name + "_class =\n"
 738             out_c += "\t\t(*env)->NewGlobalRef(env, (*env)->FindClass(env, \"org/ldk/impl/bindings$" + struct_name + "$" + var_name + "\"));\n"
 739             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_class != NULL);\n"
 740             out_c += "\t" + struct_name + "_" + var_name + "_meth = (*env)->GetMethodID(env, " + struct_name + "_" + var_name + "_class, \"<init>\", \"(" + init_meth_jty_strs[var_name] + ")V\");\n"
 741             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_meth != NULL);\n"
 742         out_c = out_c + "}\n"
 743         return out_c
 744
 745     def c_complex_enum_pass_ty(self, struct_name):
 746         return "jobject"
 747
 748     def c_constr_native_complex_enum(self, struct_name, variant, c_params):
 749         ret = "(*env)->NewObject(env, " + struct_name + "_" + variant + "_class, " + struct_name + "_" + variant + "_meth"
 750         for param in c_params:
 751             ret = ret + ", " + param
 752         return ret + ")"
 753
 754     def native_c_map_trait(self, struct_name, field_vars, flattened_field_vars, field_fns, trait_doc_comment):
 755         out_java_trait = ""
 756         out_java = ""
 757
 758         # First generate most of the Java code, note that we need information about java method argument strings for C
 759         out_java_trait = out_java_trait + self.hu_struct_file_prefix
 760         if trait_doc_comment is not None:
 761             out_java_trait += "/**\n * " + trait_doc_comment.replace("\n", "\n * ") + "\n */\n"
 762         out_java_trait += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
 763         out_java_trait = out_java_trait + "public class " + struct_name.replace("LDK","") + " extends CommonBase {\n"
 764         out_java_trait = out_java_trait + "\tfinal bindings." + struct_name + " bindings_instance;\n"
 765         out_java_trait = out_java_trait + "\t" + struct_name.replace("LDK", "") + "(Object _dummy, long ptr) { super(ptr); bindings_instance = null; }\n"
 766         out_java_trait = out_java_trait + "\tprivate " + struct_name.replace("LDK", "") + "(bindings." + struct_name + " arg"
 767         for var in flattened_field_vars:
 768             if isinstance(var, ConvInfo):
 769                 out_java_trait = out_java_trait + ", " + var.java_hu_ty + " " + var.arg_name
 770             else:
 771                 out_java_trait = out_java_trait + ", bindings." + var[0] + " " + var[1]
 772         out_java_trait = out_java_trait + ") {\n"
 773         out_java_trait = out_java_trait + "\t\tsuper(bindings." + struct_name + "_new(arg"
 774         for var in flattened_field_vars:
 775             if isinstance(var, ConvInfo):
 776                 if var.from_hu_conv is not None:
 777                     out_java_trait = out_java_trait + ", " + var.from_hu_conv[0]
 778                 else:
 779                     out_java_trait = out_java_trait + ", " + var.arg_name
 780             else:
 781                 out_java_trait = out_java_trait + ", " + var[1]
 782         out_java_trait = out_java_trait + "));\n"
 783         out_java_trait = out_java_trait + "\t\tthis.ptrs_to.add(arg);\n"
 784         for var in flattened_field_vars:
 785             if isinstance(var, ConvInfo):
 786                 if var.from_hu_conv is not None and var.from_hu_conv[1] != "":
 787                     out_java_trait = out_java_trait + "\t\t" + var.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n"
 788             else:
 789                 out_java_trait = out_java_trait + "\t\tthis.ptrs_to.add(" + var[1] + ");\n"
 790         out_java_trait += f"""          this.bindings_instance = arg;
 791         }}
 792         @Override @SuppressWarnings("deprecation")
 793         protected void finalize() throws Throwable {{
 794                 if (ptr != 0) {{ bindings.{struct_name.replace("LDK","")}_free(ptr); }} super.finalize();
 795         }}
 796         /**
 797          * Destroys the object, freeing associated resources. After this call, any access
 798          * to this object may result in a SEGFAULT or worse.
 799          *
 800          * You should generally NEVER call this method. You should let the garbage collector
 801          * do this for you when it finalizes objects. However, it may be useful for types
 802          * which represent locks and should be closed immediately to avoid holding locks
 803          * until the GC runs.
 804          */
 805         public void destroy() {{
 806                 if (ptr != 0) {{ bindings.{struct_name.replace("LDK","")}_free(ptr); }}
 807                 ptr = 0;
 808         }}
 809 """
 810
 811         java_trait_constr = "\tprivate static class " + struct_name + "Holder { " + struct_name.replace("LDK", "") + " held; }\n"
 812         java_trait_constr = java_trait_constr + "\tpublic static " + struct_name.replace("LDK", "") + " new_impl(" + struct_name.replace("LDK", "") + "Interface arg"
 813         for var in flattened_field_vars:
 814             if isinstance(var, ConvInfo):
 815                 java_trait_constr = java_trait_constr + ", " + var.java_hu_ty + " " + var.arg_name
 816             else:
 817                 # Ideally we'd be able to take any instance of the interface, but our C code can only represent
 818                 # Java-implemented version, so we require users pass a Java implementation here :/
 819                 java_trait_constr = java_trait_constr + ", " + var[0].replace("LDK", "") + "." + var[0].replace("LDK", "") + "Interface " + var[1] + "_impl"
 820         java_trait_constr = java_trait_constr + ") {\n\t\tfinal " + struct_name + "Holder impl_holder = new " + struct_name + "Holder();\n"
 821         java_trait_constr = java_trait_constr + "\t\timpl_holder.held = new " + struct_name.replace("LDK", "") + "(new bindings." + struct_name + "() {\n"
 822         out_java_trait = out_java_trait + "\tpublic static interface " + struct_name.replace("LDK", "") + "Interface {\n"
 823         out_java = out_java + "\tpublic interface " + struct_name + " {\n"
 824         java_meths = []
 825         for fn_line in field_fns:
 826             java_meth_descr = "("
 827             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 828                 out_java = out_java + "\t\t " + fn_line.ret_ty_info.java_ty + " " + fn_line.fn_name + "("
 829                 java_trait_constr = java_trait_constr + "\t\t\t@Override public " + fn_line.ret_ty_info.java_ty + " " + fn_line.fn_name + "("
 830                 out_java_trait += "\t\t/**\n\t\t * " + fn_line.docs.replace("\n", "\n\t\t * ") + "\n\t\t */\n"
 831                 out_java_trait = out_java_trait + "\t\t" + fn_line.ret_ty_info.java_hu_ty + " " + fn_line.fn_name + "("
 832
 833                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
 834                     if idx >= 1:
 835                         out_java = out_java + ", "
 836                         java_trait_constr = java_trait_constr + ", "
 837                         out_java_trait = out_java_trait + ", "
 838                     out_java = out_java + arg_conv_info.java_ty + " " + arg_conv_info.arg_name
 839                     out_java_trait = out_java_trait + arg_conv_info.java_hu_ty + " " + arg_conv_info.arg_name
 840                     java_trait_constr = java_trait_constr + arg_conv_info.java_ty + " " + arg_conv_info.arg_name
 841                     java_meth_descr = java_meth_descr + arg_conv_info.java_fn_ty_arg
 842                 java_meth_descr = java_meth_descr + ")" + fn_line.ret_ty_info.java_fn_ty_arg
 843                 java_meths.append((fn_line.fn_name, java_meth_descr))
 844
 845                 out_java = out_java + ");\n"
 846                 out_java_trait = out_java_trait + ");\n"
 847                 java_trait_constr = java_trait_constr + ") {\n"
 848
 849                 for arg_info in fn_line.args_ty:
 850                     if arg_info.to_hu_conv is not None:
 851                         java_trait_constr = java_trait_constr + "\t\t\t\t" + arg_info.to_hu_conv.replace("\n", "\n\t\t\t\t") + "\n"
 852
 853                 if fn_line.ret_ty_info.java_ty != "void":
 854                     java_trait_constr = java_trait_constr + "\t\t\t\t" + fn_line.ret_ty_info.java_hu_ty + " ret = arg." + fn_line.fn_name + "("
 855                 else:
 856                     java_trait_constr = java_trait_constr + "\t\t\t\targ." + fn_line.fn_name + "("
 857
 858                 for idx, arg_info in enumerate(fn_line.args_ty):
 859                     if idx != 0:
 860                         java_trait_constr = java_trait_constr + ", "
 861                     if arg_info.to_hu_conv_name is not None:
 862                         java_trait_constr = java_trait_constr + arg_info.to_hu_conv_name
 863                     else:
 864                         java_trait_constr = java_trait_constr + arg_info.arg_name
 865
 866                 java_trait_constr += ");\n"
 867                 java_trait_constr += "\t\t\t\tReference.reachabilityFence(arg);\n"
 868                 if fn_line.ret_ty_info.java_ty != "void":
 869                     if fn_line.ret_ty_info.from_hu_conv is not None:
 870                         java_trait_constr = java_trait_constr + "\t\t\t\t" + fn_line.ret_ty_info.java_ty + " result = " + fn_line.ret_ty_info.from_hu_conv[0] + ";\n"
 871                         if fn_line.ret_ty_info.from_hu_conv[1] != "":
 872                             java_trait_constr = java_trait_constr + "\t\t\t\t" + fn_line.ret_ty_info.from_hu_conv[1].replace("this", "impl_holder.held") + ";\n"
 873                         #if fn_line.ret_ty_info.rust_obj in result_types:
 874                         java_trait_constr = java_trait_constr + "\t\t\t\treturn result;\n"
 875                     else:
 876                         java_trait_constr = java_trait_constr + "\t\t\t\treturn ret;\n"
 877                 java_trait_constr = java_trait_constr + "\t\t\t}\n"
 878         java_trait_constr = java_trait_constr + "\t\t}"
 879         for var in field_vars:
 880             if isinstance(var, ConvInfo):
 881                 java_trait_constr = java_trait_constr + ", " + var.arg_name
 882             else:
 883                 java_trait_constr += ", " + var[1] + ".new_impl(" + var[1] + "_impl"
 884                 suptrait_constr = ""
 885                 for suparg in var[2]:
 886                     if isinstance(suparg, ConvInfo):
 887                         suptrait_constr += ", " + suparg.arg_name
 888                     else:
 889                         suptrait_constr += ", " + suparg[1] + "_impl"
 890                 java_trait_constr += suptrait_constr + ").bindings_instance"
 891                 for suparg in var[2]:
 892                     if isinstance(suparg, ConvInfo):
 893                         java_trait_constr += ", " + suparg.arg_name
 894                     else:
 895                         java_trait_constr += ", " + suparg[1] + ".new_impl("
 896                         # Blindly assume that we can just strip the first arg to build the args for the supertrait
 897                         java_trait_constr += suptrait_constr.split(", ", 1)[1]
 898                         java_trait_constr += ").bindings_instance"
 899         out_java_trait = out_java_trait + "\t}\n"
 900         out_java_trait = out_java_trait + java_trait_constr + ");\n\t\treturn impl_holder.held;\n\t}\n"
 901
 902         out_java = out_java + "\t}\n"
 903
 904         out_java = out_java + "\tpublic static native long " + struct_name + "_new(" + struct_name + " impl"
 905         for var in flattened_field_vars:
 906             if isinstance(var, ConvInfo):
 907                 out_java = out_java + ", " + var.java_ty + " " + var.arg_name
 908             else:
 909                 out_java = out_java + ", " + var[0] + " " + var[1]
 910         out_java = out_java + ");\n"
 911
 912         # Now that we've written out our java code (and created java_meths), generate C
 913         out_c = "typedef struct " + struct_name + "_JCalls {\n"
 914         out_c = out_c + "\tatomic_size_t refcnt;\n"
 915         out_c = out_c + "\tJavaVM *vm;\n"
 916         out_c = out_c + "\tjweak o;\n"
 917         for var in flattened_field_vars:
 918             if isinstance(var, ConvInfo):
 919                 # We're a regular ol' field
 920                 pass
 921             else:
 922                 # We're a supertrait
 923                 out_c = out_c + "\t" + var[0] + "_JCalls* " + var[1] + ";\n"
 924         for fn in field_fns:
 925             if fn.fn_name != "free" and fn.fn_name != "cloned":
 926                 out_c = out_c + "\tjmethodID " + fn.fn_name + "_meth;\n"
 927         out_c = out_c + "} " + struct_name + "_JCalls;\n"
 928
 929         for fn_line in field_fns:
 930             if fn_line.fn_name == "free":
 931                 out_c = out_c + "static void " + struct_name + "_JCalls_free(void* this_arg) {\n"
 932                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 933                 out_c = out_c + "\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n"
 934                 out_c += "\t\t" + self.construct_jenv().replace("\n", "\n\t\t").strip() + "\n"
 935                 out_c = out_c + "\t\t(*env)->DeleteWeakGlobalRef(env, j_calls->o);\n"
 936                 out_c += "\t\t" + self.deconstruct_jenv().replace("\n", "\n\t\t").strip() + "\n"
 937                 out_c = out_c + "\t\tFREE(j_calls);\n"
 938                 out_c = out_c + "\t}\n}\n"
 939
 940         for idx, fn_line in enumerate(field_fns):
 941             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 942                 assert fn_line.ret_ty_info.ty_info.get_full_rust_ty()[1] == ""
 943                 out_c = out_c + fn_line.ret_ty_info.ty_info.get_full_rust_ty()[0] + " " + fn_line.fn_name + "_" + struct_name + "_jcall("
 944                 if fn_line.self_is_const:
 945                     out_c = out_c + "const void* this_arg"
 946                 else:
 947                     out_c = out_c + "void* this_arg"
 948
 949                 for idx, arg in enumerate(fn_line.args_ty):
 950                     out_c = out_c + ", " + arg.ty_info.get_full_rust_ty()[0] + " " + arg.arg_name + arg.ty_info.get_full_rust_ty()[1]
 951
 952                 out_c = out_c + ") {\n"
 953                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 954                 out_c += "\t" + self.construct_jenv().replace("\n", "\n\t").strip() + "\n"
 955
 956                 for arg_info in fn_line.args_ty:
 957                     if arg_info.ret_conv is not None:
 958                         out_c = out_c + "\t" + arg_info.ret_conv[0].replace('\n', '\n\t')
 959                         out_c = out_c + arg_info.arg_name
 960                         out_c = out_c + arg_info.ret_conv[1].replace('\n', '\n\t') + "\n"
 961
 962                 out_c = out_c + "\tjobject obj = (*env)->NewLocalRef(env, j_calls->o);\n\tCHECK(obj != NULL);\n"
 963                 if fn_line.ret_ty_info.c_ty.endswith("Array"):
 964                     out_c = out_c + "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 965                 elif fn_line.ret_ty_info.c_ty == "void":
 966                     out_c += "\t(*env)->CallVoidMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 967                 elif fn_line.ret_ty_info.java_hu_ty == "String" or "org/ldk/enums" in fn_line.ret_ty_info.java_fn_ty_arg:
 968                     # Manually write out String methods as they're just an Object
 969                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 970                 elif not fn_line.ret_ty_info.passed_as_ptr:
 971                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->Call" + fn_line.ret_ty_info.java_ty.title() + "Method(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 972                 else:
 973                     out_c = out_c + "\tuint64_t ret = (*env)->CallLongMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 974
 975                 for idx, arg_info in enumerate(fn_line.args_ty):
 976                     if arg_info.ret_conv is not None:
 977                         out_c = out_c + ", " + arg_info.ret_conv_name
 978                     else:
 979                         out_c = out_c + ", " + arg_info.arg_name
 980                 out_c = out_c + ");\n"
 981
 982                 out_c += "\tif (UNLIKELY((*env)->ExceptionCheck(env))) {\n"
 983                 out_c += "\t\t(*env)->ExceptionDescribe(env);\n"
 984                 out_c += "\t\t(*env)->FatalError(env, \"A call to " + fn_line.fn_name + " in " + struct_name + " from rust threw an exception.\");\n"
 985                 out_c += "\t}\n"
 986
 987                 if fn_line.ret_ty_info.arg_conv is not None:
 988                     out_c += "\t" + fn_line.ret_ty_info.arg_conv.replace("\n", "\n\t") + "\n"
 989                     out_c += "\t" + self.deconstruct_jenv().replace("\n", "\n\t").strip() + "\n"
 990                     out_c += "\treturn " + fn_line.ret_ty_info.arg_conv_name + ";\n"
 991                 else:
 992                     out_c += "\t" + self.deconstruct_jenv().replace("\n", "\n\t").strip() + "\n"
 993                     if not fn_line.ret_ty_info.passed_as_ptr and fn_line.ret_ty_info.c_ty != "void":
 994                         out_c += "\treturn ret;\n"
 995
 996                 out_c = out_c + "}\n"
 997
 998         # If we can, write out a clone function whether we need one or not, as we use them in moving to rust
 999         can_clone_with_ptr = True
1000         for var in field_vars:
1001             if isinstance(var, ConvInfo):
1002                 can_clone_with_ptr = False
1003         if can_clone_with_ptr:
1004             out_c = out_c + "static void " + struct_name + "_JCalls_cloned(" + struct_name + "* new_obj) {\n"
1005             out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) new_obj->this_arg;\n"
1006             out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n"
1007             for var in flattened_field_vars:
1008                 if not isinstance(var, ConvInfo):
1009                     out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->" + var[2].replace(".", "->") + "->refcnt, 1, memory_order_release);\n"
1010             out_c = out_c + "}\n"
1011
1012         out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (" + self.c_fn_args_pfx + ", jobject o"
1013         for var in flattened_field_vars:
1014             if isinstance(var, ConvInfo):
1015                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
1016             else:
1017                 out_c = out_c + ", jobject " + var[1]
1018         out_c = out_c + ") {\n"
1019
1020         out_c = out_c + "\tjclass c = (*env)->GetObjectClass(env, o);\n"
1021         out_c = out_c + "\tCHECK(c != NULL);\n"
1022         out_c = out_c + "\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n"
1023         out_c = out_c + "\tatomic_init(&calls->refcnt, 1);\n"
1024         out_c = out_c + "\tDO_ASSERT((*env)->GetJavaVM(env, &calls->vm) == 0);\n"
1025         out_c = out_c + "\tcalls->o = (*env)->NewWeakGlobalRef(env, o);\n"
1026
1027         for (fn_name, java_meth_descr) in java_meths:
1028             if fn_name != "free" and fn_name != "cloned":
1029                 out_c = out_c + "\tcalls->" + fn_name + "_meth = (*env)->GetMethodID(env, c, \"" + fn_name + "\", \"" + java_meth_descr + "\");\n"
1030                 out_c = out_c + "\tCHECK(calls->" + fn_name + "_meth != NULL);\n"
1031
1032         for var in flattened_field_vars:
1033             if isinstance(var, ConvInfo) and var.arg_conv is not None:
1034                 out_c = out_c + "\n\t" + var.arg_conv.replace("\n", "\n\t") +"\n"
1035         out_c = out_c + "\n\t" + struct_name + " ret = {\n"
1036         out_c = out_c + "\t\t.this_arg = (void*) calls,\n"
1037         for fn_line in field_fns:
1038             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
1039                 out_c = out_c + "\t\t." + fn_line.fn_name + " = " + fn_line.fn_name + "_" + struct_name + "_jcall,\n"
1040             elif fn_line.fn_name == "free":
1041                 out_c = out_c + "\t\t.free = " + struct_name + "_JCalls_free,\n"
1042             else:
1043                 out_c = out_c + "\t\t.cloned = " + struct_name + "_JCalls_cloned,\n"
1044         for var in field_vars:
1045             if isinstance(var, ConvInfo):
1046                 if var.arg_conv_name is not None:
1047                     out_c = out_c + "\t\t." + var.arg_name + " = " + var.arg_conv_name + ",\n"
1048                     out_c = out_c + "\t\t.set_" + var.arg_name + " = NULL,\n"
1049                 else:
1050                     out_c = out_c + "\t\t." + var.var_name + " = " + var.var_name + ",\n"
1051                     out_c = out_c + "\t\t.set_" + var.var_name + " = NULL,\n"
1052             else:
1053                 out_c += "\t\t." + var[1] + " = " + var[0] + "_init(env, clz, " + var[1]
1054                 for suparg in var[2]:
1055                     if isinstance(suparg, ConvInfo):
1056                         out_c = out_c + ", " + suparg.arg_name
1057                     else:
1058                         out_c = out_c + ", " + suparg[1]
1059                 out_c += "),\n"
1060         out_c = out_c + "\t};\n"
1061         for var in flattened_field_vars:
1062             if not isinstance(var, ConvInfo):
1063                 out_c = out_c + "\tcalls->" + var[1] + " = ret." + var[2] + ".this_arg;\n"
1064         out_c = out_c + "\treturn ret;\n"
1065         out_c = out_c + "}\n"
1066
1067         out_c = out_c + self.c_fn_ty_pfx + "int64_t " + self.c_fn_name_define_pfx(struct_name + "_new", True) + "jobject o"
1068         for var in flattened_field_vars:
1069             if isinstance(var, ConvInfo):
1070                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
1071             else:
1072                 out_c = out_c + ", jobject " + var[1]
1073         out_c = out_c + ") {\n"
1074         out_c = out_c + "\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n"
1075         out_c = out_c + "\t*res_ptr = " + struct_name + "_init(env, clz, o"
1076         for var in flattened_field_vars:
1077             if isinstance(var, ConvInfo):
1078                 out_c = out_c + ", " + var.arg_name
1079             else:
1080                 out_c = out_c + ", " + var[1]
1081         out_c = out_c + ");\n"
1082         out_c = out_c + "\treturn tag_ptr(res_ptr, true);\n"
1083         out_c = out_c + "}\n"
1084
1085         for var in flattened_field_vars:
1086             if not isinstance(var, ConvInfo):
1087                 out_java_trait += "\n\t/**\n"
1088                 out_java_trait += "\t * Gets the underlying " + var[1] + ".\n"
1089                 out_java_trait += "\t */\n"
1090                 underscore_name = ''.join('_' + c.lower() if c.isupper() else c for c in var[1]).strip('_')
1091                 out_java_trait += "\tpublic " + var[1] + " get_" + underscore_name + "() {\n"
1092                 out_java_trait += "\t\t" + var[1] + " res = new " + var[1] + "(null, bindings." + struct_name + "_get_" + var[1] + "(this.ptr));\n"
1093                 out_java_trait += "\t\tres.ptrs_to.add(this);\n"
1094                 out_java_trait += "\t\treturn res;\n"
1095                 out_java_trait += "\t}\n"
1096                 out_java_trait += "\n"
1097
1098                 out_java += "\tpublic static native long " + struct_name + "_get_" + var[1] + "(long arg);\n"
1099
1100                 out_c += "JNIEXPORT int64_t JNICALL Java_org_ldk_impl_bindings_" + struct_name + "_1get_1" + var[1] + "(JNIEnv *env, jclass clz, int64_t arg) {\n"
1101                 out_c += "\t" + struct_name + " *inp = (" + struct_name + " *)untag_ptr(arg);\n"
1102                 out_c += "\treturn tag_ptr(&inp->" + var[2] + ", false);\n"
1103                 out_c += "}\n"
1104
1105         return (out_java, out_java_trait, out_c)
1106
1107     def trait_struct_inc_refcnt(self, ty_info):
1108         base_conv = "\nif (" + ty_info.var_name + "_conv.free == " + ty_info.rust_obj + "_JCalls_free) {\n"
1109         base_conv = base_conv + "\t// If this_arg is a JCalls struct, then we need to increment the refcnt in it.\n"
1110         base_conv = base_conv + "\t" + ty_info.rust_obj + "_JCalls_cloned(&" + ty_info.var_name + "_conv);\n}"
1111         return base_conv
1112
1113     def map_complex_enum(self, struct_name, variant_list, camel_to_snake, enum_doc_comment):
1114         java_hu_type = struct_name.replace("LDK", "").replace("COption", "Option")
1115         out_java_enum = ""
1116         out_java = ""
1117         out_c = ""
1118
1119         out_java_enum += (self.hu_struct_file_prefix)
1120         out_java_enum += "\n/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
1121         out_java_enum += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
1122         out_java_enum += ("public class " + java_hu_type + " extends CommonBase {\n")
1123         out_java_enum += ("\tprivate " + java_hu_type + "(Object _dummy, long ptr) { super(ptr); }\n")
1124         out_java_enum += ("\t@Override @SuppressWarnings(\"deprecation\")\n")
1125         out_java_enum += ("\tprotected void finalize() throws Throwable {\n")
1126         out_java_enum += ("\t\tsuper.finalize();\n")
1127         out_java_enum += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK", "") + "_free(ptr); }\n")
1128         out_java_enum += ("\t}\n")
1129         out_java_enum += ("\tstatic " + java_hu_type + " constr_from_ptr(long ptr) {\n")
1130         out_java_enum += ("\t\tbindings." + struct_name + " raw_val = bindings." + struct_name + "_ref_from_ptr(ptr);\n")
1131         java_hu_subclasses = ""
1132
1133         init_meth_jty_strs = {}
1134
1135         out_java +=  ("\tpublic static class " + struct_name + " {\n")
1136         out_java +=  ("\t\tprivate " + struct_name + "() {}\n")
1137         for var in variant_list:
1138             out_java +=  ("\t\tpublic final static class " + var.var_name + " extends " + struct_name + " {\n")
1139             if var.var_docs is not None:
1140                 java_hu_subclasses += "\t/**\n\t * " + var.var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
1141             java_hu_subclasses += "\tpublic final static class " + var.var_name + " extends " + java_hu_type + " {\n"
1142             out_java_enum += ("\t\tif (raw_val.getClass() == bindings." + struct_name + "." + var.var_name + ".class) {\n")
1143             out_java_enum += ("\t\t\treturn new " + var.var_name + "(ptr, (bindings." + struct_name + "." + var.var_name + ")raw_val);\n")
1144             init_meth_jty_str = ""
1145             init_meth_params = ""
1146             init_meth_body = ""
1147             hu_conv_body = ""
1148             for idx, (field_ty, field_docs) in enumerate(var.fields):
1149                 if idx > 0:
1150                     init_meth_params = init_meth_params + ", "
1151
1152                 java_ty = field_ty.java_ty
1153                 if field_ty.java_fn_ty_arg.startswith("L") and field_ty.java_fn_ty_arg.endswith(";"):
1154                     # If this is a simple enum, we have to reference it in the low-level bindings differently:
1155                     java_ty = field_ty.java_fn_ty_arg.strip("L;").replace("/", ".")
1156                 out_java += "\t\t\tpublic " + java_ty + " " + field_ty.arg_name + ";\n"
1157                 if field_docs is not None:
1158                     java_hu_subclasses += "\t\t/**\n\t\t * " + field_docs.replace("\n", "\n\t\t * ") + "\n\t\t*/\n"
1159                 java_hu_subclasses += "\t\t"
1160                 if field_ty.nullable:
1161                     java_hu_subclasses += "@Nullable "
1162                 java_hu_subclasses += "public final " + self.fully_qualified_hu_ty_path(field_ty) + " " + field_ty.arg_name + ";\n"
1163                 init_meth_params = init_meth_params + java_ty + " " + field_ty.arg_name
1164
1165                 init_meth_body = init_meth_body + "this." + field_ty.arg_name + " = " + field_ty.arg_name + "; "
1166                 if field_ty.to_hu_conv is not None:
1167                     hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.java_ty + " " + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
1168                     hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.to_hu_conv.replace("\n", "\n\t\t\t") + "\n"
1169                     hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = " + field_ty.to_hu_conv_name + ";\n"
1170                 else:
1171                     hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
1172                 init_meth_jty_str = init_meth_jty_str + field_ty.java_fn_ty_arg
1173             out_java +=  ("\t\t\t" + var.var_name + "(" + init_meth_params + ") { ")
1174             out_java +=  (init_meth_body)
1175             out_java +=  ("}\n")
1176             out_java += ("\t\t}\n")
1177             out_java_enum += ("\t\t}\n")
1178             java_hu_subclasses = java_hu_subclasses + "\t\tprivate " + var.var_name + "(long ptr, bindings." + struct_name + "." + var.var_name + " obj) {\n\t\t\tsuper(null, ptr);\n"
1179             java_hu_subclasses = java_hu_subclasses + hu_conv_body
1180             java_hu_subclasses = java_hu_subclasses + "\t\t}\n\t}\n"
1181             init_meth_jty_strs[var.var_name] = init_meth_jty_str
1182         out_java += ("\t\tstatic native void init();\n")
1183         out_java += ("\t}\n")
1184         out_java_enum += ("\t\tassert false; return null; // Unreachable without extending the (internal) bindings interface\n\t}\n\n")
1185         out_java_enum += (java_hu_subclasses)
1186         out_java += ("\tstatic { " + struct_name + ".init(); }\n")
1187         out_java += ("\tpublic static native " + struct_name + " " + struct_name + "_ref_from_ptr(long ptr);\n");
1188
1189         out_c += (self.c_complex_enum_pfx(struct_name, [x.var_name for x in variant_list], init_meth_jty_strs))
1190
1191         out_c += (self.c_fn_ty_pfx + self.c_complex_enum_pass_ty(struct_name) + " " + self.c_fn_name_define_pfx(struct_name + "_ref_from_ptr", True) + self.ptr_c_ty + " ptr) {\n")
1192         out_c += ("\t" + struct_name + " *obj = (" + struct_name + "*)untag_ptr(ptr);\n")
1193         out_c += ("\tswitch(obj->tag) {\n")
1194         for var in variant_list:
1195             out_c += ("\t\tcase " + struct_name + "_" + var.var_name + ": {\n")
1196             c_params = []
1197             for idx, (field_map, field_docs) in enumerate(var.fields):
1198                 if field_map.ret_conv is not None:
1199                     out_c += ("\t\t\t" + field_map.ret_conv[0].replace("\n", "\n\t\t\t"))
1200                     if var.tuple_variant:
1201                         out_c += "obj->" + camel_to_snake(var.var_name)
1202                     else:
1203                         out_c += "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name
1204                     out_c += (field_map.ret_conv[1].replace("\n", "\n\t\t\t") + "\n")
1205                     c_params.append(field_map.ret_conv_name)
1206                 else:
1207                     if var.tuple_variant:
1208                         c_params.append("obj->" + camel_to_snake(var.var_name))
1209                     else:
1210                         c_params.append("obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name)
1211             out_c += ("\t\t\treturn " + self.c_constr_native_complex_enum(struct_name, var.var_name, c_params) + ";\n")
1212             out_c += ("\t\t}\n")
1213         out_c += ("\t\tdefault: abort();\n")
1214         out_c += ("\t}\n}\n")
1215         return (out_java, out_java_enum, out_c)
1216
1217     def map_opaque_struct(self, struct_name, struct_doc_comment):
1218         out_opaque_struct_human = ""
1219         out_opaque_struct_human += self.hu_struct_file_prefix
1220         out_opaque_struct_human += "\n/**\n * " + struct_doc_comment.replace("\n", "\n * ") + "\n */\n"
1221         out_opaque_struct_human += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
1222         hu_name = struct_name.replace("LDKC2Tuple", "TwoTuple").replace("LDKC3Tuple", "ThreeTuple").replace("LDK", "")
1223         out_opaque_struct_human += ("public class " + hu_name + " extends CommonBase")
1224         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1225             out_opaque_struct_human += (" implements AutoCloseable")
1226         out_opaque_struct_human += (" {\n")
1227         out_opaque_struct_human += ("\t" + hu_name + "(Object _dummy, long ptr) { super(ptr); }\n")
1228         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1229             out_opaque_struct_human += ("\t@Override public void close() {\n")
1230         else:
1231             out_opaque_struct_human += ("\t@Override @SuppressWarnings(\"deprecation\")\n")
1232             out_opaque_struct_human += ("\tprotected void finalize() throws Throwable {\n")
1233             out_opaque_struct_human += ("\t\tsuper.finalize();\n")
1234         out_opaque_struct_human += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n")
1235         out_opaque_struct_human += ("\t}\n\n")
1236         return out_opaque_struct_human
1237
1238     def map_tuple(self, struct_name):
1239         return self.map_opaque_struct(struct_name, "A Tuple")
1240
1241     def map_result(self, struct_name, res_map, err_map):
1242         human_ty = struct_name.replace("LDKCResult", "Result")
1243         java_hu_struct = ""
1244         java_hu_struct += self.hu_struct_file_prefix
1245         java_hu_struct += "public class " + human_ty + " extends CommonBase {\n"
1246         java_hu_struct += "\tprivate " + human_ty + "(Object _dummy, long ptr) { super(ptr); }\n"
1247         java_hu_struct += "\tprotected void finalize() throws Throwable {\n"
1248         java_hu_struct += "\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); } super.finalize();\n"
1249         java_hu_struct += "\t}\n\n"
1250         java_hu_struct += "\tstatic " + human_ty + " constr_from_ptr(long ptr) {\n"
1251         java_hu_struct += "\t\tif (bindings." + struct_name.replace("LDK", "") + "_is_ok(ptr)) {\n"
1252         java_hu_struct += "\t\t\treturn new " + human_ty + "_OK(null, ptr);\n"
1253         java_hu_struct += "\t\t} else {\n"
1254         java_hu_struct += "\t\t\treturn new " + human_ty + "_Err(null, ptr);\n"
1255         java_hu_struct += "\t\t}\n"
1256         java_hu_struct += "\t}\n"
1257
1258         java_hu_struct += "\tpublic static final class " + human_ty + "_OK extends " + human_ty + " {\n"
1259
1260         if res_map.java_hu_ty != "void":
1261             java_hu_struct += "\t\tpublic final " + res_map.java_hu_ty + " res;\n"
1262         java_hu_struct += "\t\tprivate " + human_ty + "_OK(Object _dummy, long ptr) {\n"
1263         java_hu_struct += "\t\t\tsuper(_dummy, ptr);\n"
1264         if res_map.java_hu_ty == "void":
1265             pass
1266         elif res_map.to_hu_conv is not None:
1267             java_hu_struct += "\t\t\t" + res_map.java_ty + " res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1268             java_hu_struct += "\t\t\t" + res_map.to_hu_conv.replace("\n", "\n\t\t\t")
1269             java_hu_struct += "\n\t\t\tthis.res = " + res_map.to_hu_conv_name + ";\n"
1270         else:
1271             java_hu_struct += "\t\t\tthis.res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1272         java_hu_struct += "\t\t}\n"
1273         java_hu_struct += "\t}\n\n"
1274
1275         java_hu_struct += "\tpublic static final class " + human_ty + "_Err extends " + human_ty + " {\n"
1276         if err_map.java_hu_ty != "void":
1277             java_hu_struct += "\t\tpublic final " + err_map.java_hu_ty + " err;\n"
1278         java_hu_struct += "\t\tprivate " + human_ty + "_Err(Object _dummy, long ptr) {\n"
1279         java_hu_struct += "\t\t\tsuper(_dummy, ptr);\n"
1280         if err_map.java_hu_ty == "void":
1281             pass
1282         elif err_map.to_hu_conv is not None:
1283             java_hu_struct += "\t\t\t" + err_map.java_ty + " err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1284             java_hu_struct += "\t\t\t" + err_map.to_hu_conv.replace("\n", "\n\t\t\t")
1285             java_hu_struct += "\n\t\t\tthis.err = " + err_map.to_hu_conv_name + ";\n"
1286         else:
1287             java_hu_struct += "\t\t\tthis.err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1288         java_hu_struct += "\t\t}\n"
1289
1290         java_hu_struct += "\t}\n\n"
1291         return java_hu_struct
1292
1293     def map_function(self, argument_types, c_call_string, method_name, meth_n, return_type_info, struct_meth, default_constructor_args, takes_self, takes_self_as_ref, args_known, type_mapping_generator, doc_comment):
1294         out_java = ""
1295         out_c = ""
1296         out_java_struct = None
1297
1298         out_java += ("\tpublic static native ")
1299         out_c += (self.c_fn_ty_pfx)
1300         out_c += (return_type_info.c_ty)
1301         out_java += (return_type_info.java_ty)
1302         if return_type_info.ret_conv is not None:
1303             ret_conv_pfx, ret_conv_sfx = return_type_info.ret_conv
1304         out_java += (" " + method_name + "(")
1305         have_args = len(argument_types) > 1 or (len(argument_types) > 0 and argument_types[0].c_ty != "void")
1306         out_c += (" " + self.c_fn_name_define_pfx(method_name, have_args))
1307
1308         for idx, arg_conv_info in enumerate(argument_types):
1309             if idx != 0:
1310                 out_java += (", ")
1311                 out_c += (", ")
1312             if arg_conv_info.c_ty != "void":
1313                 out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
1314                 out_java += (arg_conv_info.java_ty + " " + arg_conv_info.arg_name)
1315
1316         out_java_struct = ""
1317         extra_java_struct_out = ""
1318         if not args_known:
1319             out_java_struct += ("\t// Skipped " + method_name + "\n")
1320         else:
1321             if doc_comment is not None:
1322                 out_java_struct += "\t/**\n\t * " + doc_comment.replace("\n", "\n\t * ") + "\n\t */\n"
1323             if return_type_info.nullable:
1324                 out_java_struct += "\t@Nullable\n"
1325             if not takes_self:
1326                 if meth_n == "new":
1327                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " of("
1328                 elif meth_n == "default":
1329                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " with_default("
1330                 else:
1331                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " " + meth_n + "("
1332             elif meth_n == "clone_ptr" or (struct_meth.startswith("LDKCResult") and (meth_n == "get_ok" or meth_n == "get_err")):
1333                 out_java_struct += ("\t" + return_type_info.java_hu_ty + " " + meth_n + "(")
1334             else:
1335                 if meth_n == "hash" and return_type_info.java_hu_ty == "long":
1336                     extra_java_struct_out = "\t@Override public int hashCode() {\n"
1337                     extra_java_struct_out += "\t\treturn (int)this.hash();\n"
1338                     extra_java_struct_out += "\t}\n"
1339                 elif meth_n == "eq" and return_type_info.java_hu_ty == "boolean":
1340                     extra_java_struct_out = "\t@Override public boolean equals(Object o) {\n"
1341                     extra_java_struct_out += "\t\tif (!(o instanceof " + struct_meth + ")) return false;\n"
1342                     extra_java_struct_out += "\t\treturn this.eq((" + struct_meth + ")o);\n"
1343                     extra_java_struct_out += "\t}\n"
1344                 if meth_n == "wait":
1345                     meth_n = "wait_indefinite"
1346                 out_java_struct += ("\tpublic " + return_type_info.java_hu_ty + " " + meth_n + "(")
1347             for idx, arg in enumerate(argument_types):
1348                 if idx != 0:
1349                     if not takes_self or idx > 1:
1350                         out_java_struct += ", "
1351                 elif takes_self:
1352                     continue
1353                 if arg.java_ty != "void":
1354                     if arg.arg_name in default_constructor_args:
1355                         assert not arg.nullable
1356                         for explode_idx, explode_arg in enumerate(default_constructor_args[arg.arg_name]):
1357                             if explode_idx != 0:
1358                                 out_java_struct += (", ")
1359                             out_java_struct += (
1360                                 explode_arg.java_hu_ty + " " + arg.arg_name + "_" + explode_arg.arg_name)
1361                     else:
1362                         if arg.nullable:
1363                             out_java_struct += "@Nullable "
1364                         ty_string = self.fully_qualified_hu_ty_path(arg)
1365                         out_java_struct += ty_string + " " + arg.arg_name
1366         out_java += (");\n")
1367         out_c += (") {\n")
1368         if out_java_struct is not None:
1369             out_java_struct += (") {\n")
1370         for info in argument_types:
1371             if info.arg_conv is not None:
1372                 out_c += ("\t" + info.arg_conv.replace('\n', "\n\t") + "\n")
1373         if return_type_info.ret_conv is not None:
1374             out_c += ("\t" + ret_conv_pfx.replace('\n', '\n\t'))
1375         elif return_type_info.c_ty != "void":
1376             out_c += ("\t" + return_type_info.c_ty + " ret_val = ")
1377         else:
1378             out_c += ("\t")
1379         if c_call_string is None:
1380             out_c += (method_name + "(")
1381         else:
1382             out_c += (c_call_string)
1383         for idx, info in enumerate(argument_types):
1384             if info.arg_conv_name is not None:
1385                 if idx != 0:
1386                     out_c += (", ")
1387                 elif c_call_string is not None:
1388                     continue
1389                 out_c += (info.arg_conv_name)
1390         out_c += (")")
1391         if return_type_info.ret_conv is not None:
1392             out_c += (ret_conv_sfx.replace('\n', '\n\t'))
1393         else:
1394             out_c += (";")
1395         for info in argument_types:
1396             if info.arg_conv_cleanup is not None:
1397                 out_c += ("\n\t" + info.arg_conv_cleanup.replace("\n", "\n\t"))
1398         if return_type_info.ret_conv is not None:
1399             out_c += ("\n\treturn " + return_type_info.ret_conv_name + ";")
1400         elif return_type_info.c_ty != "void":
1401             out_c += ("\n\treturn ret_val;")
1402         out_c += ("\n}\n\n")
1403
1404         if args_known:
1405             out_java_struct += ("\t\t")
1406             if return_type_info.java_ty != "void":
1407                 out_java_struct += (return_type_info.java_ty + " ret = ")
1408             out_java_struct += ("bindings." + method_name + "(")
1409             for idx, info in enumerate(argument_types):
1410                 if idx != 0:
1411                     out_java_struct += (", ")
1412                 if idx == 0 and takes_self:
1413                     out_java_struct += ("this.ptr")
1414                 elif info.arg_name in default_constructor_args:
1415                     out_java_struct += ("bindings." + info.java_hu_ty + "_new(")
1416                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1417                         if explode_idx != 0:
1418                             out_java_struct += (", ")
1419                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1420                         if explode_arg.from_hu_conv is not None:
1421                             out_java_struct += (
1422                                 explode_arg.from_hu_conv[0].replace(explode_arg.arg_name, expl_arg_name))
1423                         else:
1424                             out_java_struct += (expl_arg_name)
1425                     out_java_struct += (")")
1426                 elif info.from_hu_conv is not None:
1427                     out_java_struct += (info.from_hu_conv[0])
1428                 else:
1429                     out_java_struct += (info.arg_name)
1430             out_java_struct += (");\n")
1431
1432             # This is completely nuts. The OpenJDK JRE JIT will optimize out a object which is on
1433             # the stack, calling its finalizer immediately even if member methods are *actively
1434             # executing* on the same object, as long as said object is on the stack. There is no
1435             # concrete specification for when the optimizer is allowed to do this, and when it is
1436             # not, so there is absolutely no way to be certain that this fix suffices.
1437             #
1438             # Instead, the "Java Language Specification" says only that an object is reachable
1439             # (i.e. will not yet be finalized) if it "can be accessed in any potential continuing
1440             # computation from any live thread". To any sensible reader this would mean actively
1441             # executing a member function on an object would make it not eligible for finalization.
1442             # But, no, dear reader, this statement does not say that. Well, okay, it says that,
1443             # very explicitly in fact, but those are just, like, words, man.
1444             #
1445             # In the seemingly non-normative text further down, a few examples of things the
1446             # optimizer can do are given, including "if the values in an object's fields are
1447             # stored in registers[, t]he may then access the registers instead of the object, and
1448             # never access the object again[, implying] that the object is garbage". This appears
1449             # to fully contradict both the above statement, the API documentation in java.lang.ref
1450             # regarding when a reference is "strongly reachable", and basic common sense. There is
1451             # no concrete set of limitations stated, however, seemingly implying the JIT could
1452             # decide your code would run faster by simply garbage collecting everything
1453             # immediately, ensuring your code finishes soon, just by SEGFAULT. Thus, we're really
1454             # entirely flying blind here. We add some fences and hope that its sufficient, but
1455             # with no specification to rely on, we cannot be certain of anything.
1456             #
1457             # TL;DR: The Java Language "Specification" provides no real guarantees on when an
1458             # object will be considered available for garbage collection once the JIT kicks in, so
1459             # we put in some fences and hope to god the JIT doesn't get smarter/more broken.
1460             for idx, info in enumerate(argument_types):
1461                 if idx == 0 and takes_self:
1462                     out_java_struct += ("\t\tReference.reachabilityFence(this);\n")
1463                 elif info.arg_name in default_constructor_args:
1464                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1465                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1466                         out_java_struct += ("\t\tReference.reachabilityFence(" + expl_arg_name + ");\n")
1467                 elif info.c_ty != "void":
1468                     out_java_struct += ("\t\tReference.reachabilityFence(" + info.arg_name + ");\n")
1469
1470             if return_type_info.java_ty == "long" and return_type_info.java_hu_ty != "long":
1471                 out_java_struct += "\t\tif (ret >= 0 && ret <= 4096) { return null; }\n"
1472
1473             if return_type_info.to_hu_conv is not None:
1474                 if not takes_self:
1475                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t").replace("this",
1476                                                                                                                return_type_info.to_hu_conv_name) + "\n")
1477                 else:
1478                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t") + "\n")
1479
1480             for idx, info in enumerate(argument_types):
1481                 if idx == 0 and takes_self:
1482                     pass
1483                 elif info.arg_name in default_constructor_args:
1484                     for explode_arg in default_constructor_args[info.arg_name]:
1485                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1486                         if explode_arg.from_hu_conv is not None and return_type_info.to_hu_conv_name:
1487                             out_java_struct += ("\t\t" + explode_arg.from_hu_conv[1].replace(explode_arg.arg_name,
1488                                                                                                expl_arg_name).replace(
1489                                 "this", return_type_info.to_hu_conv_name) + ";\n")
1490                 elif info.from_hu_conv is not None and info.from_hu_conv[1] != "":
1491                     if not takes_self and return_type_info.to_hu_conv_name is not None:
1492                         out_java_struct += (
1493                             "\t\t" + info.from_hu_conv[1].replace("this", return_type_info.to_hu_conv_name).replace("\n", "\n\t\t") + ";\n")
1494                     else:
1495                         out_java_struct += ("\t\t" + info.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n")
1496
1497             if takes_self and not takes_self_as_ref:
1498                 out_java_struct += "\t\t" + argument_types[0].from_hu_conv[1].replace("\n", "\n\t\t").replace("this_arg", "this") + ";\n"
1499             if return_type_info.to_hu_conv_name is not None:
1500                 out_java_struct += ("\t\treturn " + return_type_info.to_hu_conv_name + ";\n")
1501             elif return_type_info.java_ty != "void" and return_type_info.rust_obj != "LDK" + struct_meth:
1502                 out_java_struct += ("\t\treturn ret;\n")
1503             out_java_struct += ("\t}\n\n")
1504
1505         return (out_java, out_c, out_java_struct + extra_java_struct_out)
1506
1507     def cleanup(self):
1508         pass