com.dragome.methodlogger.serverside.MethodLoggerAdapter.java Source code

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Here is the source code for com.dragome.methodlogger.serverside.MethodLoggerAdapter.java

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/*
 * Copyright (c) 2011-2014 Fernando Petrola
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.dragome.methodlogger.serverside;

import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.commons.AdviceAdapter;

public class MethodLoggerAdapter extends ClassVisitor {
    private String className;

    public MethodLoggerAdapter(ClassVisitor cv) {
        super(Opcodes.ASM5, cv);
    }

    @Override
    public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
        MethodVisitor mv;
        mv = cv.visitMethod(access, name, desc, signature, exceptions);
        mv = new MethodReturnAdapter(Opcodes.ASM5, className, access, name, desc, mv);
        return mv;
    }

    public void visit(int version, int access, String name, String signature, String superName,
            String[] interfaces) {
        className = name;
        super.visit(version, access, name, signature, superName, interfaces);
    }

}

class MethodReturnAdapter extends AdviceAdapter {
    private String name;
    private String owner;
    protected Label l0;

    public MethodReturnAdapter(int api, String owner, int access, String name, String desc, MethodVisitor mv) {
        super(Opcodes.ASM5, mv, access, name, desc);
        this.owner = owner;
        this.name = name;
    }

    public MethodReturnAdapter(MethodVisitor mv, int access, String name, String desc) {
        super(Opcodes.ASM5, mv, access, name, desc);
        this.name = name;
    }

    protected void onMethodEnter() {
        if (!isStatic()) {
            l0 = new Label();
            super.visitLabel(l0);

            super.visitVarInsn(Opcodes.ALOAD, 0);
            super.visitLdcInsn(name);
            super.visitMethodInsn(Opcodes.INVOKESTATIC, "com/dragome/methodlogger/enhancers/MethodInvocationLogger",
                    "onMethodEnter", "(Ljava/lang/Object;Ljava/lang/String;)V", false);
        }
        super.onMethodEnter();
    }

    public void visitLocalVariable(String name, String desc, String signature, Label start, Label end, int index) {
        if (!isStatic())
            start = l0;

        super.visitLocalVariable(name, desc, signature, start, end, index);
    }

    private boolean isStatic() {
        return (methodAccess & Opcodes.ACC_STATIC) != 0 || name.equals("<init>");
    }

    protected void onMethodExit(int opcode) {
        if (!isStatic()) {
            super.visitVarInsn(Opcodes.ALOAD, 0);
            super.visitLdcInsn(name);
            super.visitMethodInsn(Opcodes.INVOKESTATIC, "com/dragome/methodlogger/enhancers/MethodInvocationLogger",
                    "onMethodExit", "(Ljava/lang/Object;Ljava/lang/String;)V", false);
        }
    }
}