org.krzogr.trackthread.instrument.StartMethodVisitor.java Source code

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Here is the source code for org.krzogr.trackthread.instrument.StartMethodVisitor.java

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/*
 * Copyright (C) 2015 krzogr (krzogr@gmail.com)
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

package org.krzogr.trackthread.instrument;

import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

/**
 * Visitor which performs instrumentation for Thread.start() method.
 */
public class StartMethodVisitor extends MethodVisitor {
    public StartMethodVisitor(final int api, final MethodVisitor mv) {
        super(api, mv);
    }

    public static boolean matches(final int access, final String name, final String desc) {
        return (access & Opcodes.ACC_PUBLIC) != 0 && "start".equals(name) && "()V".equals(desc);
    }

    @Override
    public void visitCode() {
        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Object", "getClass", "()Ljava/lang/Class;", false);
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "org/krzogr/trackthread/instrument/ThreadTracker",
                "threadStarting", "(Ljava/lang/Class;)V", false);

        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "org/krzogr/trackthread/ThreadListeners", "fireThreadStarting",
                "(Ljava/lang/Thread;)V", false);

        super.visitCode();
    }
}