package com.infomancers.collections.yield.asmbase;

import org.objectweb.asm.ClassAdapter;
import org.objectweb.asm.ClassVisitor;

/**
 * Copyright (c) 2007, Aviad Ben Dov
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this list
 * of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice, this
 * list of conditions and the following disclaimer in the documentation and/or other
 * materials provided with the distribution.
 * 3. Neither the name of Infomancers, Ltd. nor the names of its contributors may be
 * used to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */


/**
 * Makes sure that the class being examined is in fact
 * a sub-class of the Yielder class.
 * <p/>
 * This is necessary because during instrumentation, all we have
 * is the bytecode. Only a bytecode framework can load up the class
 * from that and check for such information.
 */
final class YielderChecker extends ClassAdapter {
    private boolean isYielder = false;


    public boolean isYielder() {
        return isYielder;
    }

    /**
     * Constructs a new {@link org.objectweb.asm.ClassAdapter} object.
     *
     * @param cv the class visitor to which this adapter must delegate calls.
     */
    public YielderChecker(ClassVisitor cv) {
        super(cv);
    }


    @Override
    public void visit(final int version, final int access, final String name, final String signature, final String superName, final String[] interfaces) {
        super.visit(version, access, name, signature, superName, interfaces);

        if (Util.isYielderClassName(superName) || Util.isYielderInHierarchyTree(superName)) {
            isYielder = true;
        }
    }
}