Tinyj2c transfer JAVA source to C source, build as standlone binary, and run without any class file. It's so small can be used to embedded device.
- A very very small java runtime
- Garbage collection
- Minimize memory footprint
- Exception stack trace
- Thread support
- Lambda support
- JDK 8+ (not only jre).
- clang/gcc/vsc.
win i686 download: https://github.com/digitalgust/mingw-w64/releases/download/release/i686-8.1.0-release-posix-dwarf-rt_v6-rev0.7z
win x64 download: https://github.com/digitalgust/mingw-w64/releases/download/release/x86_64-8.1.0-release-posix-seh-rt_v6-rev0.7z
- run build script :
/tinyj2c/posix_build.sh
Or
- git clone https://github.com/digitalgust/tinyj2c.git
- Idea open /tinyj2c/class2c , run translator.
- Clion/vs/xcode open /tinyj2c/app , compile c source and run .
- Run binary no java classes dependence.
- Java code:
package test;
public class HelloWorld {
static String str = "Hello world!";
void test() throws RuntimeException {
try {
System.out.println(str);
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String args[]) {
new HelloWorld().test();
}
}
- converted C code:
// CLASS: test/HelloWorld extends java/lang/Object
#include "metadata.h"
// generation
// globals
//struct test_HelloWorld_static {struct java_lang_String* str_0; };
struct test_HelloWorld_static static_var_test_HelloWorld = {NULL};
__refer arr_vmtable_test_HelloWorld_from_test_HelloWorld[] = {
func_test_HelloWorld_test___V //0
};
__refer arr_vmtable_test_HelloWorld_from_java_lang_Object[] = {
func_java_lang_Object_toString___Ljava_lang_String_2, //0
func_java_lang_Object_wait___V, //1
func_java_lang_Object_finalize___V, //2
func_java_lang_Object_equals__Ljava_lang_Object_2_Z, //3
func_java_lang_Object_clone___Ljava_lang_Object_2, //4
func_java_lang_Object_getClass___Ljava_lang_Class_2, //5
func_java_lang_Object_wait__J_V, //6
func_java_lang_Object_notify___V, //7
func_java_lang_Object_notifyAll___V, //8
func_java_lang_Object_hashCode___I //9
};
VMTable vmtable_test_HelloWorld[] = {
{147, 1, arr_vmtable_test_HelloWorld_from_test_HelloWorld}, //0
{5, 10, arr_vmtable_test_HelloWorld_from_java_lang_Object}, //1
};
// locals: 1
// stack: 1
// args: 1
void func_test_HelloWorld__init____V(JThreadRuntime *runtime, struct test_HelloWorld* p0){
StackItem local[1] = {0};
RStackItem rlocal[1] = {0};
StackItem stack[2];
RStackItem rstack[2];
s32 sp = 0;
StackFrame *__frame = method_enter(runtime, 1207, &rstack[0], &rlocal[0], &sp);
rlocal[0].obj = p0;
;
// line no 3 , L1842355195 , bytecode index = 0
__frame->bytecodeIndex = 0; //first
__frame->lineNo = 3;
rstack[sp++].obj = rlocal[0].obj;
// invokespecial java/lang/Object.<init>()V
sp -= 1; //pop para
// it's a empty method
method_exit(runtime);
return;
;
__ExceptionHandler:
switch (find_exception_handler_index(runtime)) {
default: goto __ExceptionHandlerNotFound;
}
__ExceptionHandlerNotFound:
method_exit(runtime);
return ;
}
void bridge_test_HelloWorld__init____V(JThreadRuntime *runtime, __refer ins, ParaItem *para, ParaItem *ret) {
func_test_HelloWorld__init____V(runtime, ins);
}
ExceptionItem arr_extable_func_test_HelloWorld_test___V[] = {
{ 0, 9, 130}
};
ExceptionTable extable_func_test_HelloWorld_test___V = {1, arr_extable_func_test_HelloWorld_test___V};
// locals: 2
// stack: 2
// args: 1
void func_test_HelloWorld_test___V(JThreadRuntime *runtime, struct test_HelloWorld* p0){
StackItem local[2] = {0};
RStackItem rlocal[2] = {0};
StackItem stack[3];
RStackItem rstack[3];
s32 sp = 0;
StackFrame *__frame = method_enter(runtime, 1208, &rstack[0], &rlocal[0], &sp);
rlocal[0].obj = p0;
// try catch :L389748355 L944266478 L1437243359 (0,9)->12
L389748355:
__frame->bytecodeIndex = 0; //try catch begin
// line no 8 , L389748355 , bytecode index = 0
__frame->bytecodeIndex = 0; //first
__frame->lineNo = 8;
// getstatic java/lang/System out Ljava/io/PrintStream;
rstack[sp].obj =static_var_java_lang_System.out_2;
sp += 1;
// getstatic test/HelloWorld str Ljava/lang/String;
rstack[sp].obj =static_var_test_HelloWorld.str_0;
sp += 1;
// invokevirtual java/io/PrintStream.println(Ljava/lang/String;)V
{
sp -= 2;
JObject *__ins = rstack[sp + 0].ins;
if (!__ins) {
rstack[sp++].obj = construct_and_throw_exception(runtime, 0, 0, 8);
goto __ExceptionHandler;
}
void (*__func_p) (JThreadRuntime *,struct java_io_PrintStream*,struct java_lang_String*) = find_method(__ins->vm_table, 19, 4);
__func_p(runtime, rstack[sp + 0].obj, rstack[sp + 1].obj);
sp += 0;
if (runtime->exception) {
rstack[sp++].obj = runtime->exception;
goto __ExceptionHandler;
}
}
L944266478:
__frame->bytecodeIndex = 9; //try catch end
// line no 11 , L944266478 , bytecode index = 9
goto L1959940703;
L1437243359:
// line no 9 , L1437243359 , bytecode index = 12
rlocal[1].obj = rstack[--sp].obj;
;
// line no 10 , L999480648 , bytecode index = 13
rstack[sp++].obj = rlocal[1].obj;
// invokevirtual java/lang/Exception.printStackTrace()V
{
sp -= 1;
JObject *__ins = rstack[sp + 0].ins;
if (!__ins) {
rstack[sp++].obj = construct_and_throw_exception(runtime, 0, 13, 10);
goto __ExceptionHandler;
}
void (*__func_p) (JThreadRuntime *,struct java_lang_Throwable*) = find_method(__ins->vm_table, 18, 4);
__func_p(runtime, rstack[sp + 0].obj);
sp += 0;
if (runtime->exception) {
rstack[sp++].obj = runtime->exception;
goto __ExceptionHandler;
}
}
L1959940703:
// line no 12 , L1959940703 , bytecode index = 17
method_exit(runtime);
return;
;
__ExceptionHandler:
switch (find_exception_handler_index(runtime)) {
case 0 : goto L1437243359;
default: goto __ExceptionHandlerNotFound;
}
__ExceptionHandlerNotFound:
method_exit(runtime);
return ;
}
void bridge_test_HelloWorld_test___V(JThreadRuntime *runtime, __refer ins, ParaItem *para, ParaItem *ret) {
func_test_HelloWorld_test___V(runtime, ins);
}
// locals: 1
// stack: 2
// args: 1
void func_test_HelloWorld_main___3Ljava_lang_String_2_V(JThreadRuntime *runtime, JArray * p0){
StackItem local[1] = {0};
RStackItem rlocal[1] = {0};
StackItem stack[3];
RStackItem rstack[3];
s32 sp = 0;
StackFrame *__frame = method_enter(runtime, 1209, &rstack[0], &rlocal[0], &sp);
rlocal[0].obj = p0;
;
// line no 15 , L1087515232 , bytecode index = 0
__frame->bytecodeIndex = 0; //first
__frame->lineNo = 15;
// new test/HelloWorld
rstack[sp++].obj = new_instance_with_classraw_index(runtime, 147);
// dup
stack[sp].j = stack[sp - 1].j;
rstack[sp].obj = rstack[sp - 1].obj;
++sp;
// invokespecial test/HelloWorld.<init>()V
{
sp -= 1;
JObject *__ins = rstack[sp + 0].ins;
if (!__ins) {
rstack[sp++].obj = construct_and_throw_exception(runtime, 0, 0, 15);
goto __ExceptionHandler;
}
func_test_HelloWorld__init____V(runtime, rstack[sp + 0].obj);
sp += 0;
if (runtime->exception) {
rstack[sp++].obj = runtime->exception;
goto __ExceptionHandler;
}
}
// invokevirtual test/HelloWorld.test()V
{
sp -= 1;
JObject *__ins = rstack[sp + 0].ins;
if (!__ins) {
rstack[sp++].obj = construct_and_throw_exception(runtime, 0, 0, 15);
goto __ExceptionHandler;
}
void (*__func_p) (JThreadRuntime *,struct test_HelloWorld*) = find_method(__ins->vm_table, 147, 0);
__func_p(runtime, rstack[sp + 0].obj);
sp += 0;
if (runtime->exception) {
rstack[sp++].obj = runtime->exception;
goto __ExceptionHandler;
}
}
;
// line no 16 , L645187727 , bytecode index = 10
method_exit(runtime);
return;
;
__ExceptionHandler:
switch (find_exception_handler_index(runtime)) {
default: goto __ExceptionHandlerNotFound;
}
__ExceptionHandlerNotFound:
method_exit(runtime);
return ;
}
void bridge_test_HelloWorld_main___3Ljava_lang_String_2_V(JThreadRuntime *runtime, __refer ins, ParaItem *para, ParaItem *ret) {
func_test_HelloWorld_main___3Ljava_lang_String_2_V(runtime, para[0].obj);
}
// locals: 0
// stack: 1
// args: 0
void func_test_HelloWorld__clinit____V(JThreadRuntime *runtime){
StackItem stack[2];
RStackItem rstack[2];
s32 sp = 0;
StackFrame *__frame = method_enter(runtime, 1210, &rstack[0], NULL, &sp);
;
// line no 4 , L1892854145 , bytecode index = 0
__frame->bytecodeIndex = 0; //first
__frame->lineNo = 4;
// ldc
rstack[sp++].obj = construct_string_with_utfraw_index(runtime, 2092);
// putstatic test/HelloWorld str Ljava/lang/String;
sp -= 1;
static_var_test_HelloWorld.str_0 = rstack[sp].obj;
method_exit(runtime);
return;
__ExceptionHandler:
switch (find_exception_handler_index(runtime)) {
default: goto __ExceptionHandlerNotFound;
}
__ExceptionHandlerNotFound:
method_exit(runtime);
return ;
}
void bridge_test_HelloWorld__clinit____V(JThreadRuntime *runtime, __refer ins, ParaItem *para, ParaItem *ret) {
func_test_HelloWorld__clinit____V(runtime);
}
License: MIT
Gust , digitalgust@163.com .
