Java Code Examples for jdk.internal.org.objectweb.asm.MethodVisitor

public static byte[] dumpT2() {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;

    cw.visit(52, ACC_PUBLIC | ACC_SUPER, "p1/T2", null, "p1/T1", null);
    {
        mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
        mv.visitCode();
        mv.visitVarInsn(ALOAD, 0);
        mv.visitMethodInsn(INVOKESPECIAL, "p1/T1", "<init>", "()V", false);
        mv.visitInsn(RETURN);
        mv.visitMaxs(1, 1);
        mv.visitEnd();
    }
    {
        mv = cw.visitMethod(ACC_PUBLIC + ACC_ABSTRACT, "m", "()I", null, null);
        mv.visitEnd();
    }
    cw.visitEnd();

    return cw.toByteArray();
}
 

@Override
public MethodVisitor visitMethod(
    final int access,
    final String name,
    final String desc,
    final String signature,
    final String[] exceptions) {
    return new MethodVisitor(Opcodes.ASM4) {
        @Override
        public AnnotationVisitor visitAnnotationDefault() {
            return new NullAnnotationVisitor();
        }

        @Override
        public AnnotationVisitor visitAnnotation(final String descriptor, final boolean visible) {
            return new NullAnnotationVisitor();
        }
    };
}
 

/**
 * Makes the given visitor visit this stack map frame.
 *
 * @param mv
 *            a method visitor.
 */
@Override
public void accept(final MethodVisitor mv) {
    switch (type) {
    case Opcodes.F_NEW:
    case Opcodes.F_FULL:
        mv.visitFrame(type, local.size(), asArray(local), stack.size(),
                asArray(stack));
        break;
    case Opcodes.F_APPEND:
        mv.visitFrame(type, local.size(), asArray(local), 0, null);
        break;
    case Opcodes.F_CHOP:
        mv.visitFrame(type, local.size(), null, 0, null);
        break;
    case Opcodes.F_SAME:
        mv.visitFrame(type, 0, null, 0, null);
        break;
    case Opcodes.F_SAME1:
        mv.visitFrame(type, 0, null, 1, asArray(stack));
        break;
    }
}
 

private static Type dup(final MethodVisitor method, final Type type, final int depth) {
    final boolean       cat2 = type.isCategory2();

    switch (depth) {
    case 0:
        method.visitInsn(cat2 ? DUP2 : DUP);
        break;
    case 1:
        method.visitInsn(cat2 ? DUP2_X1 : DUP_X1);
        break;
    case 2:
        method.visitInsn(cat2 ? DUP2_X2 : DUP_X2);
        break;
    default:
        return null; //invalid depth
    }

    return type;
}
 

@Override
public void accept(final MethodVisitor mv) {
    int[] keys = new int[this.keys.size()];
    for (int i = 0; i < keys.length; ++i) {
        keys[i] = this.keys.get(i).intValue();
    }
    Label[] labels = new Label[this.labels.size()];
    for (int i = 0; i < labels.length; ++i) {
        labels[i] = this.labels.get(i).getLabel();
    }
    mv.visitLookupSwitchInsn(dflt.getLabel(), keys, labels);
    acceptAnnotations(mv);
}
 

static MethodGenerator makeConstructor(final ClassVisitor cv) {
    final int access = 0;
    final String name = INIT;
    final String desc = DEFAULT_INIT_DESC;
    final MethodVisitor mv = cv.visitMethod(access, name, desc, null, null);
    return new MethodGenerator(mv, access, name, desc);
}
 

/**
 * Add a new method to the class, representing a rest-of version of the
 * function node.
 *
 * @param functionNode the function node to generate a method for
 *
 * @return method emitter to use for weaving this method
 */
MethodEmitter restOfMethod(final FunctionNode functionNode) {
    methodCount++;
    methodNames.add(functionNode.getName());
    final MethodVisitor mv = cw.visitMethod(
        ACC_PUBLIC | ACC_STATIC,
        functionNode.getName(),
        Type.getMethodDescriptor(functionNode.getReturnType().getTypeClass(), RewriteException.class),
        null,
        null);

    return new MethodEmitter(this, mv, functionNode);
}
 

@Override
public Type div(final MethodVisitor method, final int programPoint) {
    if (programPoint == INVALID_PROGRAM_POINT) {
        JSType.DIV_ZERO.invoke(method);
    } else {
        method.visitInvokeDynamicInsn("idiv", "(II)I", MATHBOOTSTRAP, programPoint);
    }
    return INT;
}
 

private byte[] loadClassData(String name) throws Exception {
    ClassWriter cw = new ClassWriter(0);
    MethodVisitor mv;
    switch (name) {
        case INTERFACE_NAME:
            cw.visit(V1_8, ACC_ABSTRACT | ACC_INTERFACE | ACC_PUBLIC, INTERFACE_NAME, null, "java/lang/Object", null);
            {
                mv = cw.visitMethod(ACC_PRIVATE, "privInstance", "()I", null, null);
                mv.visitCode();
                mv.visitLdcInsn(EXPECTED);
                mv.visitInsn(IRETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        case CLASS_NAME:
            cw.visit(52, ACC_SUPER | ACC_PUBLIC, CLASS_NAME, null, "java/lang/Object", new String[]{INTERFACE_NAME});
            {
                mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
                mv.visitInsn(RETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
            break;
        default:
            break;
    }
    cw.visitEnd();

    return cw.toByteArray();
}
 

private static void emitPushFields(String types, String className, MethodVisitor mv) {
    for (int i = 0; i < types.length(); ++i) {
        char tc = types.charAt(i);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
    }
}
 

@Override
public Type add(final MethodVisitor method, final int programPoint) {
    // Adding booleans in JavaScript is perfectly valid, they add as if false=0 and true=1
    if(programPoint == INVALID_PROGRAM_POINT) {
        method.visitInsn(IADD);
    } else {
        method.visitInvokeDynamicInsn("iadd", "(II)I", MATHBOOTSTRAP, programPoint);
    }
    return INT;
}
 

private static void emitPushFields(String types, String className, MethodVisitor mv) {
    for (int i = 0; i < types.length(); ++i) {
        char tc = types.charAt(i);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
    }
}
 

static MethodGenerator makeConstructor(final ClassVisitor cv) {
    final int access = 0;
    final String name = INIT;
    final String desc = DEFAULT_INIT_DESC;
    final MethodVisitor mv = cv.visitMethod(access, name, desc, null, null);
    return new MethodGenerator(mv, access, name, desc);
}
 

/**
  * Makes the given visitor visit all the instructions in this list.
  *
  * @param methodVisitor the method visitor that must visit the instructions.
  */
public void accept(final MethodVisitor methodVisitor) {
    AbstractInsnNode currentInsn = firstInsn;
    while (currentInsn != null) {
        currentInsn.accept(methodVisitor);
        currentInsn = currentInsn.nextInsn;
    }
}
 

@Override
public Type add(final MethodVisitor method, final int programPoint) {
    if(programPoint == INVALID_PROGRAM_POINT) {
        method.visitInsn(IADD);
    } else {
        method.visitInvokeDynamicInsn("iadd", "(II)I", MATHBOOTSTRAP, programPoint);
    }
    return INT;
}
 

/**
 * Makes the given visitor visit all of the instructions in this list.
 *
 * @param mv
 *            the method visitor that must visit the instructions.
 */
public void accept(final MethodVisitor mv) {
    AbstractInsnNode insn = first;
    while (insn != null) {
        insn.accept(mv);
        insn = insn.next;
    }
}
 

void addCarrierAccessor(BinderClassWriter cw) {
    MethodVisitor mv = cw.visitMethod(ACC_FINAL, "carrier", "()Ljava/lang/Class;", null, null);
    mv.visitCode();
    mv.visitLdcInsn(cw.makeConstantPoolPatch(carrier));
    mv.visitTypeInsn(CHECKCAST, Type.getInternalName(Class.class));
    mv.visitInsn(ARETURN);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}
 

/**
 * Creates a new {@link LocalVariablesSorter}.
 *
 * @param api the ASM API version implemented by this visitor. Must be one
 *        of {@link Opcodes#ASM4}.
 * @param access access flags of the adapted method.
 * @param desc the method's descriptor (see {@link Type Type}).
 * @param mv the method visitor to which this adapter delegates calls.
 */
protected LocalVariablesSorter(
    final int api,
    final int access,
    final String desc,
    final MethodVisitor mv)
{
    super(api, mv);
    Type[] args = Type.getArgumentTypes(desc);
    nextLocal = (Opcodes.ACC_STATIC & access) == 0 ? 1 : 0;
    for (int i = 0; i < args.length; i++) {
        nextLocal += args[i].getSize();
    }
    firstLocal = nextLocal;
}
 

private static byte[] loadC(boolean redefine) {
    ClassWriter cw = new ClassWriter(0);

    cw.visit(52, ACC_SUPER | ACC_PUBLIC, "C", null, "java/lang/Object", null);
    {
        MethodVisitor mv;

        mv = cw.visitMethod(ACC_PUBLIC | ACC_STATIC, "m", "()V", null, null);
        mv.visitCode();

        // First time we run we will:
        // 1) Cache resolution errors
        // 2) Redefine the class / method
        // 3) Try to read the resolution errors that were cached
        //
        // The redefined method will never run, throw error to be sure
        if (redefine) {
            createThrowRuntimeExceptionCode(mv, "The redefined method was called");
        } else {
            createMethodBody(mv);
        }
        mv.visitMaxs(3, 0);
        mv.visitEnd();
    }
    cw.visitEnd();
    return cw.toByteArray();
}
 

@Override
public Type add(final MethodVisitor method, final int programPoint) {
    if(programPoint == INVALID_PROGRAM_POINT) {
        method.visitInsn(LADD);
    } else {
        method.visitInvokeDynamicInsn("ladd", "(JJ)J", MATHBOOTSTRAP, programPoint);
    }
    return LONG;
}
 

@Override
public void accept(final MethodVisitor mv) {
    int[] keys = new int[this.keys.size()];
    for (int i = 0; i < keys.length; ++i) {
        keys[i] = this.keys.get(i).intValue();
    }
    Label[] labels = new Label[this.labels.size()];
    for (int i = 0; i < labels.length; ++i) {
        labels[i] = this.labels.get(i).getLabel();
    }
    mv.visitLookupSwitchInsn(dflt.getLabel(), keys, labels);
    acceptAnnotations(mv);
}
 

@Override
public Type load(final MethodVisitor method, final int slot) {
    assert slot != -1;
    method.visitVarInsn(ALOAD, slot);
    return this;
}
 

@Override
public Type ldc(final MethodVisitor method, final Object c) {
    throw new UnsupportedOperationException("ldc " + c);
}
 

public TryCatchBlockSorter(final MethodVisitor mv, final int access,
        final String name, final String desc, final String signature,
        final String[] exceptions) {
    this(Opcodes.ASM5, mv, access, name, desc, signature, exceptions);
}
 

protected MethodRemapper(final int api, final MethodVisitor mv,
        final Remapper remapper) {
    super(api, mv);
    this.remapper = remapper;
}
 

@Override
public Type loadUndefined(final MethodVisitor method) {
    method.visitLdcInsn(UNDEFINED_DOUBLE);
    return NUMBER;
}
 

@Override
public Type loadUndefined(final MethodVisitor method) {
    throw new UnsupportedOperationException("load undefined");
}
 

@Override
public Type newarray(final MethodVisitor method) {
    method.visitIntInsn(NEWARRAY, T_DOUBLE);
    return this;
}
 

@Override
public Type loadUndefined(final MethodVisitor method) {
    method.visitLdcInsn(UNDEFINED_INT);
    return INT;
}
 

@Override
public void _return(final MethodVisitor method) {
    method.visitInsn(LRETURN);
}