/***
* ASM Guide
* Copyright (c) 2007 Eric Bruneton
* 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 the copyright holders 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.
*/
package ch6.sec1;
import static org.objectweb.asm.Opcodes.ACC_INTERFACE;
import static org.objectweb.asm.Opcodes.ACC_PUBLIC;
import static org.objectweb.asm.Opcodes.ACC_STATIC;
import static org.objectweb.asm.Opcodes.ATHROW;
import static org.objectweb.asm.Opcodes.GETSTATIC;
import static org.objectweb.asm.Opcodes.INVOKESTATIC;
import static org.objectweb.asm.Opcodes.IRETURN;
import static org.objectweb.asm.Opcodes.LADD;
import static org.objectweb.asm.Opcodes.LSUB;
import static org.objectweb.asm.Opcodes.PUTSTATIC;
import static org.objectweb.asm.Opcodes.RETURN;
import java.util.Iterator;
import java.util.List;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.ClassNode;
import org.objectweb.asm.tree.FieldInsnNode;
import org.objectweb.asm.tree.FieldNode;
import org.objectweb.asm.tree.InsnList;
import org.objectweb.asm.tree.InsnNode;
import org.objectweb.asm.tree.MethodInsnNode;
import org.objectweb.asm.tree.MethodNode;
import ch5.sec1.ClassTransformer;
/**
* ASM Guide example class.
*
* @author Eric Bruneton
*/
public class AddTimerTransformer extends ClassTransformer {
public AddTimerTransformer(ClassTransformer ct) {
super(ct);
}
public void transform(ClassNode cn) {
if ((cn.access & ACC_INTERFACE) == 0) {
for (MethodNode mn : (List<MethodNode>) cn.methods) {
if ("<init>".equals(mn.name) || "<clinit>".equals(mn.name)) {
continue;
}
InsnList insns = mn.instructions;
if (insns.size() == 0) {
continue;
}
Iterator j = insns.iterator();
while (j.hasNext()) {
AbstractInsnNode in = (AbstractInsnNode) j.next();
int op = in.getOpcode();
if ((op >= IRETURN && op <= RETURN) || op == ATHROW) {
InsnList il = new InsnList();
il.add(new FieldInsnNode(GETSTATIC, cn.name, "timer", "J"));
il.add(new MethodInsnNode(INVOKESTATIC, "java/lang/System",
"currentTimeMillis", "()J"));
il.add(new InsnNode(LADD));
il.add(new FieldInsnNode(PUTSTATIC, cn.name, "timer", "J"));
if (in.getPrevious() == null) {
continue;
}
insns.insert(in.getPrevious(), il);
}
}
InsnList il = new InsnList();
il.add(new FieldInsnNode(GETSTATIC, cn.name, "timer", "J"));
il.add(new MethodInsnNode(INVOKESTATIC, "java/lang/System",
"currentTimeMillis", "()J"));
il.add(new InsnNode(LSUB));
il.add(new FieldInsnNode(PUTSTATIC, cn.name, "timer", "J"));
insns.insert(il);
mn.maxStack += 4;
}
int acc = ACC_PUBLIC + ACC_STATIC;
cn.fields.add(new FieldNode(acc, "timer", "J", null, null));
}
super.transform(cn);
}
}