Java GeneratorAdapter.dupX2方法代碼示例

import org.objectweb.asm.commons.GeneratorAdapter; //導入方法依賴的package包/類
public void emit(C context, ObjExpr objx, GeneratorAdapter gen){
    Label endLabel = gen.newLabel();
    Label faultLabel = gen.newLabel();

    gen.visitLineNumber(line, gen.mark());
    gen.getStatic(objx.objtype, objx.thunkNameStatic(siteIndex),ObjExpr.ILOOKUP_THUNK_TYPE);
    gen.dup();  //thunk, thunk
    target.emit(C.EXPRESSION, objx, gen); //thunk,thunk,target
    gen.visitLineNumber(line, gen.mark());
    gen.dupX2();                          //target,thunk,thunk,target
    gen.invokeInterface(ObjExpr.ILOOKUP_THUNK_TYPE, Method.getMethod("Object get(Object)")); //target,thunk,result
    gen.dupX2();                          //result,target,thunk,result
    gen.visitJumpInsn(IF_ACMPEQ, faultLabel); //result,target
    gen.pop();                                //result
    gen.goTo(endLabel);

    gen.mark(faultLabel);    //result,target
    gen.swap();              //target,result
    gen.pop();               //target
 gen.dup();               //target,target
    gen.getStatic(objx.objtype, objx.siteNameStatic(siteIndex),ObjExpr.KEYWORD_LOOKUPSITE_TYPE);  //target,target,site
    gen.swap();              //target,site,target
    gen.invokeInterface(ObjExpr.ILOOKUP_SITE_TYPE,
                        Method.getMethod("clojure.lang.ILookupThunk fault(Object)"));    //target,new-thunk
 gen.dup();   //target,new-thunk,new-thunk
 gen.putStatic(objx.objtype, objx.thunkNameStatic(siteIndex),ObjExpr.ILOOKUP_THUNK_TYPE);  //target,new-thunk
 gen.swap();              //new-thunk,target
 gen.invokeInterface(ObjExpr.ILOOKUP_THUNK_TYPE, Method.getMethod("Object get(Object)")); //result

    gen.mark(endLabel);
    if(context == C.STATEMENT)
        gen.pop();
}
 

import org.objectweb.asm.commons.GeneratorAdapter; //導入方法依賴的package包/類
@Override
@Unsafe(Unsafe.ASM_API)
public byte[] transform(String name, String transformedName, byte[] basicClass) {
	String srgName = this.srgName;
	if (!AlchemyEngine.isRuntimeDeobfuscationEnabled())
		srgName = DeobfuscatingRemapper.instance().mapMethodName(transformedName, this.srgName, desc);
	AlchemyTransformerManager.transform("<proxy>" + name + "|" + transformedName + "#" + proxyMethod.name + proxyMethod.signature
			+ "\n->  " + target + "#" + srgName + desc);
	ClassReader reader = new ClassReader(basicClass);
	ClassWriter writer = ASMHelper.newClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES);
	ClassNode node = new ClassNode(ASM5);
	reader.accept(node, 0);
	MethodNode oldMethod = null, newMethod = new MethodNode(proxyMethod.access, proxyMethod.name, proxyMethod.desc, proxyMethod.signature,
			proxyMethod.exceptions.toArray(new String[proxyMethod.exceptions.size()]));
	for (MethodNode method : node.methods)
		if (method.name.equals(proxyMethod.name) && method.desc.equals(proxyMethod.desc)) {
			oldMethod = method;
			GeneratorAdapter adapter = new GeneratorAdapter(newMethod, method.access, method.name, method.desc);
			Type owner = Type.getType(ASMHelper.getClassDesc(target));
			Method targetMethod = new Method(srgName, desc);
			switch (opcode) {
				case INVOKESTATIC:
					adapter.loadArgs();
					adapter.invokeStatic(owner, targetMethod);
					break;
				case INVOKEVIRTUAL:
					adapter.loadArgs();
					adapter.invokeVirtual(owner, targetMethod);
					break;
				case INVOKESPECIAL:
					adapter.invokeStatic(Type.getType(AlchemyEngine.class), new Method("lookup",
							"()Ljava/lang/invoke/MethodHandles$Lookup;"));
					adapter.push(srgName);
					Type args[] = Type.getArgumentTypes(desc);
					adapter.visitFieldInsn(GETSTATIC, "java/lang/Void", "TYPE", "Ljava/lang/Class;");
					adapter.push(args.length);
					adapter.newArray(Type.getType(Class.class));
					for (Type arg : args) {
						adapter.dup();
						adapter.push(arg);
						adapter.arrayStore(Type.getType(Class.class));
					}
					adapter.invokeStatic(Type.getType(MethodType.class), new Method("methodType",
							"(Ljava/lang/Class;[Ljava/lang/Class;)Ljava/lang/invoke/MethodType;"));
					adapter.push(owner);
					adapter.dupX2();
					adapter.invokeVirtual(Type.getType(MethodHandles.Lookup.class), new Method("findSpecial",
							"(Ljava/lang/Class;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/Class;)Ljava/lang/invoke/MethodHandle;"));
					adapter.loadArgs();
					adapter.invokeVirtual(Type.getType(MethodHandle.class), new Method("invoke", proxyMethod.desc));
					break;
				case INVOKEINTERFACE:
					adapter.loadArgs();
					adapter.invokeInterface(owner, targetMethod);
					break;
				default:
					AlchemyRuntimeException.onException(new RuntimeException("Unsupported opcode: " + opcode));
			}
			adapter.returnValue();
			adapter.endMethod();
			break;
		}
	node.methods.remove(oldMethod);
	node.methods.add(newMethod);
	node.accept(writer);
	return writer.toByteArray();
}