Java ClassVisitor.visitMethod方法代码示例

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 *  Generate test with an invokedynamic, a static bootstrap method without extra args and
 *  args to the target method.
 */
private void generateMethodTest2(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "test2", "()V",
      null, null);
  MethodType mt = MethodType.methodType(
          CallSite.class, MethodHandles.Lookup.class, String.class, MethodType.class);
  Handle bootstrap = new Handle( Opcodes.H_INVOKESTATIC, Type.getInternalName(InvokeCustom.class),
      "bsmLookupStatic", mt.toMethodDescriptorString(), false);
  mv.visitLdcInsn(new Boolean(true));
  mv.visitLdcInsn(new Byte((byte) 127));
  mv.visitLdcInsn(new Character('c'));
  mv.visitLdcInsn(new Short((short) 1024));
  mv.visitLdcInsn(new Integer(123456));
  mv.visitLdcInsn(new Float(1.2f));
  mv.visitLdcInsn(new Long(123456789));
  mv.visitLdcInsn(new Double(3.5123456789));
  mv.visitLdcInsn("String");
  mv.visitInvokeDynamicInsn("targetMethodTest2", "(ZBCSIFJDLjava/lang/String;)V", bootstrap);
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 *  Generate test with an invokedynamic, a static bootstrap method with an extra arg that is a
 *  MethodHandle of kind invokespecial.
 */
private void generateMethodTest4(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "test4", "()V",
      null, null);
  MethodType mt = MethodType.methodType(CallSite.class, MethodHandles.Lookup.class, String.class,
      MethodType.class, MethodHandle.class);
  Handle bootstrap = new Handle( Opcodes.H_INVOKESTATIC, Type.getInternalName(InvokeCustom.class),
      "bsmCreateCallSite", mt.toMethodDescriptorString(), false);
  mv.visitTypeInsn(Opcodes.NEW, Type.getInternalName(InvokeCustom.class));
  mv.visitInsn(Opcodes.DUP);
  mv.visitMethodInsn(
      Opcodes.INVOKESPECIAL, Type.getInternalName(InvokeCustom.class), "<init>", "()V", false);
  mv.visitInvokeDynamicInsn("targetMethodTest5", "(Linvokecustom/InvokeCustom;)V", bootstrap,
      new Handle( Opcodes.H_INVOKESPECIAL, Type.getInternalName(Super.class),
          "targetMethodTest5", "()V", false));
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 *  Generate test with an invokedynamic, a static bootstrap method with an extra arg that is a
 *  MethodHandle of kind invoke interface. The target method is a default method into an interface
 *  that shadows another default method from a super interface.
 */
private void generateMethodTest5(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "test5", "()V",
      null, null);
  MethodType mt = MethodType.methodType(CallSite.class, MethodHandles.Lookup.class, String.class,
      MethodType.class, MethodHandle.class);
  Handle bootstrap = new Handle(Opcodes.H_INVOKESTATIC, Type.getInternalName(InvokeCustom.class),
      "bsmCreateCallCallingtargetMethodTest6", mt.toMethodDescriptorString(), false);
  mv.visitTypeInsn(Opcodes.NEW, Type.getInternalName(InvokeCustom.class));
  mv.visitInsn(Opcodes.DUP);
  mv.visitMethodInsn(
      Opcodes.INVOKESPECIAL, Type.getInternalName(InvokeCustom.class), "<init>", "()V", false);
  mv.visitInvokeDynamicInsn("targetMethodTest6", "(Linvokecustom/I;)V", bootstrap,
      new Handle(Opcodes.H_INVOKEINTERFACE, Type.getInternalName(I.class),
          "targetMethodTest6", "()V", true));
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 *  Generate test with an invokedynamic, a static bootstrap method with an extra arg that is a
 *  MethodHandle of kind invoke interface. The target method is a method into an interface
 *  that is shadowed by another definition into a sub interfaces.
 */
private void generateMethodTest7(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "test7", "()V",
      null, null);
  MethodType mt = MethodType.methodType(CallSite.class, MethodHandles.Lookup.class, String.class,
      MethodType.class, MethodHandle.class);
  Handle bootstrap = new Handle(Opcodes.H_INVOKESTATIC, Type.getInternalName(InvokeCustom.class),
      "bsmCreateCallCallingtargetMethodTest8", mt.toMethodDescriptorString(), false);
  mv.visitTypeInsn(Opcodes.NEW, Type.getInternalName(InvokeCustom.class));
  mv.visitInsn(Opcodes.DUP);
  mv.visitMethodInsn(
      Opcodes.INVOKESPECIAL, Type.getInternalName(InvokeCustom.class), "<init>", "()V", false);
  mv.visitInvokeDynamicInsn("targetMethodTest8", "(Linvokecustom/J;)V", bootstrap,
      new Handle(Opcodes.H_INVOKEINTERFACE, Type.getInternalName(J.class),
          "targetMethodTest8", "()V", true));
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 *  Generate test with an invokedynamic, a static bootstrap method with an extra arg that is a
 *  MethodHandle of kind invoke virtual. The target method is a method into an interface that is
 *  not shadowed by an implementation into a classes implementing the interface.
 */
private void generateMethodTest8(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "test8", "()V",
      null, null);
  MethodType mt = MethodType.methodType(CallSite.class, MethodHandles.Lookup.class, String.class,
      MethodType.class, MethodHandle.class);
  Handle bootstrap = new Handle(Opcodes.H_INVOKESTATIC, Type.getInternalName(InvokeCustom.class),
      "bsmCreateCallCallingtargetMethodTest9", mt.toMethodDescriptorString(), false);
  mv.visitTypeInsn(Opcodes.NEW, Type.getInternalName(InvokeCustom.class));
  mv.visitInsn(Opcodes.DUP);
  mv.visitMethodInsn(
      Opcodes.INVOKESPECIAL, Type.getInternalName(InvokeCustom.class), "<init>", "()V", false);
  mv.visitInvokeDynamicInsn("targetMethodTest9", "(Linvokecustom/InvokeCustom;)V", bootstrap,
      new Handle(Opcodes.H_INVOKEVIRTUAL, Type.getInternalName(InvokeCustom.class),
          "targetMethodTest9", "()V", false));
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
private void writeEqualsMethod(ClassVisitor cw, Type generatedType) {
    MethodVisitor methodVisitor = cw.visitMethod(Opcodes.ACC_PUBLIC, "equals", EQUALS_METHOD_DESCRIPTOR, null, null);
    methodVisitor.visitCode();

    // if (arg == this) { return true; }
    methodVisitor.visitVarInsn(ALOAD, 0);
    methodVisitor.visitVarInsn(ALOAD, 1);
    Label notSameLabel = new Label();
    methodVisitor.visitJumpInsn(IF_ACMPNE, notSameLabel);
    methodVisitor.visitInsn(ICONST_1);
    methodVisitor.visitInsn(IRETURN);

    // if (!(age instanceof GeneratedView)) { return false; }
    methodVisitor.visitLabel(notSameLabel);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitTypeInsn(INSTANCEOF, GENERATED_VIEW_TYPE.getInternalName());
    Label generatedViewLabel = new Label();
    methodVisitor.visitJumpInsn(IFNE, generatedViewLabel);
    methodVisitor.visitInsn(ICONST_0);
    methodVisitor.visitInsn(IRETURN);

    // return state.equals(((GeneratedView)arg).__view_state());
    methodVisitor.visitLabel(generatedViewLabel);
    putStateFieldValueOnStack(methodVisitor, generatedType);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitTypeInsn(CHECKCAST, GENERATED_VIEW_TYPE.getInternalName());
    methodVisitor.visitMethodInsn(INVOKEINTERFACE, GENERATED_VIEW_TYPE.getInternalName(), "__view_state__", GET_VIEW_STATE_METHOD_DESCRIPTOR, true);
    methodVisitor.visitMethodInsn(INVOKEINTERFACE, GENERATED_VIEW_STATE_TYPE_NAME, "equals", EQUALS_METHOD_DESCRIPTOR, true);
    finishVisitingMethod(methodVisitor, Opcodes.IRETURN);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 * Makes the given class visitor visit this method.
 * 
 * @param cv
 *            a class visitor.
 */
public void accept(final ClassVisitor cv) {
    String[] exceptions = new String[this.exceptions.size()];
    this.exceptions.toArray(exceptions);
    MethodVisitor mv = cv.visitMethod(access, name, desc, signature,
            exceptions);
    if (mv != null) {
        accept(mv);
    }
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
private void generateMethodMain(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(
          Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "main", "([Ljava/lang/String;)V", null, null);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test1", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test2", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test3", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test4", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test5", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test6", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test7", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test8", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test9", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test10", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test11", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test12", "()V", false);
  mv.visitMethodInsn(
      Opcodes.INVOKESTATIC, Type.getInternalName(InvokeCustom.class), "test13", "()V", false);
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 *  Generate test with an invokedynamic, a static bootstrap method without extra args and no arg
 *  to the target method.
 */
private void generateMethodTest1(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "test1", "()V",
          null, null);
  MethodType mt =
      MethodType.methodType(
          CallSite.class, MethodHandles.Lookup.class, String.class, MethodType.class);
  Handle bootstrap = new Handle( Opcodes.H_INVOKESTATIC, Type.getInternalName(InvokeCustom.class),
      "bsmLookupStatic", mt.toMethodDescriptorString(), false);
  mv.visitInvokeDynamicInsn("targetMethodTest1", "()V", bootstrap);
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
/**
 *  Generate test with an invokedynamic, a static bootstrap method with extra args and no arg
 *  to the target method.
 */
private void generateMethodTest3(ClassVisitor cv) {
  MethodVisitor mv = cv.visitMethod(Opcodes.ACC_PUBLIC + Opcodes.ACC_STATIC, "test3", "()V",
      null, null);
  MethodType mt = MethodType.methodType(
          CallSite.class, MethodHandles.Lookup.class, String.class, MethodType.class, int.class,
      long.class, float.class, double.class);
  Handle bootstrap = new Handle( Opcodes.H_INVOKESTATIC, Type.getInternalName(InvokeCustom.class),
      "bsmLookupStaticWithExtraArgs", mt.toMethodDescriptorString(), false);
  mv.visitInvokeDynamicInsn("targetMethodTest3", "()V", bootstrap, new Integer(1),
      new Long(123456789), new Float(123.456), new Double(123456.789123));
  mv.visitInsn(Opcodes.RETURN);
  mv.visitMaxs(-1, -1);
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
public MethodWriter(int access, Method method, ClassVisitor cw, BitSet statements, CompilerSettings settings) {
    super(Opcodes.ASM5, cw.visitMethod(access, method.getName(), method.getDescriptor(), null, null),
            access, method.getName(), method.getDescriptor());

    this.statements = statements;
    this.settings = settings;
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
private MethodVisitor declareMethod(ClassVisitor visitor, String methodName, String methodDescriptor, String methodSignature, int access) {
    MethodVisitor methodVisitor = visitor.visitMethod(access, methodName, methodDescriptor, methodSignature, NO_EXCEPTIONS);
    methodVisitor.visitCode();
    return methodVisitor;
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
@Contract("null, null, null, null, null, null, null, null, _, _ -> fail")
static void generateMethodProxy(ClassVisitor cv, Method interfaceMethod,
                                Type reflectorClass, Type targetClass, Type interfaceClass,
                                String targetMethodName, Type[] targetParameters, Type targetReturnType,
                                int flags, int mhIndex) {
    String methodName = interfaceMethod.getName();
    String methodDesc = Type.getMethodDescriptor(interfaceMethod);
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, methodName, methodDesc, null, null);
    GeneratorAdapter adapter = new GeneratorAdapter(mv, ACC_PUBLIC, methodName, methodDesc);
    adapter.visitCode();

    /* Load MethodHandle, if required */
    loadMH(adapter, reflectorClass, flags, mhIndex);

    /* Load instance, if required */
    loadInstance(adapter, reflectorClass, targetClass, flags);

    /* Load method parameters into stack */
    loadArguments(adapter, Type.getArgumentTypes(interfaceMethod), targetParameters, (flags & Magic.TARGET_CLASS_VISIBILITY_PUBLIC) != 0);

    if((flags & Magic.REFLECTOR_METHOD_USE_METHODHANDLE) != 0) {
        /* Build MethodHandle descriptor (invokeExact is polymorphic) */
        String mhDescriptor = convertDesc(targetParameters,
                ((flags & Magic.RETURN_TYPE_PUBLIC) != 0 ? targetReturnType : OBJECT),
                (flags & Magic.REFLECTOR_METHOD_USE_INSTANCE) != 0 ? ((flags & Magic.TARGET_CLASS_VISIBILITY_PUBLIC) != 0 ? targetClass : OBJECT) : null);

        /* Select right MethodHandle invoker */
        String mhInvoker = (flags & Magic.TARGET_CLASS_VISIBILITY_PUBLIC) != 0 && (flags & Magic.RETURN_TYPE_PUBLIC) != 0 ? "invokeExact" : "invoke";

        /* Invoke MethodHandle */
        mv.visitMethodInsn(INVOKEVIRTUAL, MH.getInternalName(), mhInvoker, mhDescriptor, false);
    } else {
        /* Figure out what opcode to use */
        int opCode = (flags & Magic.REFLECTOR_METHOD_USE_INVOKEINTERFACE) != 0 ?
                ((flags & Magic.REFLECTOR_METHOD_USE_INSTANCE) != 0 ? INVOKEINTERFACE : INVOKESTATIC)
                :
                ((flags & Magic.REFLECTOR_METHOD_USE_INSTANCE) != 0 ? INVOKEVIRTUAL : INVOKESTATIC);

        /* Build descriptor & select target class */
        String targetDescriptor = convertDesc(targetParameters, targetReturnType, null);
        String targetName = (flags & Magic.REFLECTOR_METHOD_USE_INVOKEINTERFACE) != 0 ? interfaceClass.getInternalName() : targetClass.getInternalName();

        /* Invoke method */
        adapter.visitMethodInsn(opCode, targetName, targetMethodName, targetDescriptor, (flags & Magic.REFLECTOR_METHOD_USE_INVOKEINTERFACE) != 0);
    }

    /* Return */
    handleReturn(adapter, interfaceMethod, targetReturnType);
    adapter.returnValue();

    /* End method */
    adapter.endMethod();
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
@Contract("null, null, null, null, null, null, _, _ -> fail")
static void generateFieldReadMethod(ClassVisitor cv, Method interfaceMethod,
                                    Type reflectorClass, Type targetClass, Type fieldType, String fieldName,
                                    int flags, int mhIndex) {
    String methodName = interfaceMethod.getName();
    String methodDesc = Type.getMethodDescriptor(interfaceMethod);
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, methodName, methodDesc, null, null);
    GeneratorAdapter adapter = new GeneratorAdapter(mv, ACC_PUBLIC, methodName, methodDesc);
    adapter.visitCode();

    /* Load MethodHandle, if required */
    loadMH(adapter, reflectorClass, flags, mhIndex);

    /* Load instance, if required */
    loadInstance(adapter, reflectorClass, targetClass, flags);

    if((flags & Magic.REFLECTOR_METHOD_USE_METHODHANDLE) != 0) {
        /* Build MethodHandle descriptor */
        String mhDescriptor = newDescriptor()
                .accepts((flags & Magic.REFLECTOR_METHOD_USE_INSTANCE) != 0 ? ((flags & Magic.TARGET_CLASS_VISIBILITY_PUBLIC) != 0 ? targetClass : OBJECT).getDescriptor() : "")
                .returns(fieldType.getDescriptor())
                .toString();

        /* Select right MethodHandle invoker */
        String mhInvoker = (flags & Magic.TARGET_CLASS_VISIBILITY_PUBLIC) != 0 && (flags & Magic.RETURN_TYPE_PUBLIC) != 0 ? "invokeExact" : "invoke";

        /* Invoke MethodHandle */
        adapter.visitMethodInsn(INVOKEVIRTUAL, MH.getInternalName(), mhInvoker, mhDescriptor, false);
    } else {
        if((flags & Magic.REFLECTOR_METHOD_USE_INSTANCE) != 0)
            adapter.getField(targetClass, fieldName, fieldType);
        else
            adapter.getStatic(targetClass, fieldName, fieldType);
    }

    /* Return */
    handleReturn(adapter, interfaceMethod, fieldType);
    adapter.returnValue();

    /* End method */
    adapter.endMethod();
}
 

import org.objectweb.asm.ClassVisitor; //导入方法依赖的package包/类
@Contract("null, null, null, null, null, null, _, _ -> fail")
static void generateFieldWriteMethod(ClassVisitor cv, Method interfaceMethod,
                                     Type reflectorClass, Type targetClass, Type fieldType, String fieldName,
                                     int flags, int mhIndex) {
    String methodName = interfaceMethod.getName();
    String methodDesc = Type.getMethodDescriptor(interfaceMethod);
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, methodName, methodDesc, null, null);
    GeneratorAdapter adapter = new GeneratorAdapter(mv, ACC_PUBLIC, methodName, methodDesc);
    adapter.visitCode();

    /* Load MethodHandle, if required */
    loadMH(adapter, reflectorClass, flags, mhIndex);

    /* Load instance, if required */
    loadInstance(adapter, reflectorClass, targetClass, flags);

    /* Load method parameter into stack */
    adapter.loadArg(0);

    if((flags & Magic.REFLECTOR_METHOD_USE_METHODHANDLE) != 0) {
        /* Build MethodHandle descriptor */
        String mhDescriptor = newDescriptor()
                .accepts(((flags & Magic.REFLECTOR_METHOD_USE_INSTANCE) != 0 ?
                        ((flags & Magic.TARGET_CLASS_VISIBILITY_PUBLIC) != 0 ? targetClass : OBJECT).getDescriptor(): "")
                        + fieldType.getDescriptor())
                .toString();

        /* Select right MethodHandle invoker */
        String mhInvoker = (flags & Magic.TARGET_CLASS_VISIBILITY_PUBLIC) != 0 && (flags & Magic.RETURN_TYPE_PUBLIC) != 0 ? "invokeExact" : "invoke";

        /* Invoke MethodHandle */
        adapter.visitMethodInsn(INVOKEVIRTUAL, MH.getInternalName(), mhInvoker, mhDescriptor, false);
    } else {
        if((flags & Magic.REFLECTOR_METHOD_USE_INSTANCE) != 0)
            adapter.putField(targetClass, fieldName, fieldType);
        else
            adapter.putStatic(targetClass, fieldName, fieldType);
    }

    /* Return */
    adapter.returnValue();

    /* End method */
    adapter.endMethod();
}