org.eclipse.objectteams.otredyn.bytecode.asm.CreateSwitchForAccessAdapter.java Source code

Introduction

Here is the source code for org.eclipse.objectteams.otredyn.bytecode.asm.CreateSwitchForAccessAdapter.java

Source

/**********************************************************************
 * This file is part of "Object Teams Dynamic Runtime Environment"
 * 
 * Copyright 2009, 2012 Oliver Frank and others.
 * 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Please visit http://www.eclipse.org/objectteams for updates and contact.
 * 
 * Contributors:
 *      Oliver Frank - Initial API and implementation
 *      Stephan Herrmann - Initial API and implementation
 **********************************************************************/
package org.eclipse.objectteams.otredyn.bytecode.asm;

import org.eclipse.objectteams.otredyn.bytecode.AbstractBoundClass;
import org.eclipse.objectteams.otredyn.bytecode.Method;
import org.eclipse.objectteams.otredyn.transformer.names.ClassNames;
import org.eclipse.objectteams.otredyn.transformer.names.ConstantMembers;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.tree.InsnNode;
import org.objectweb.asm.tree.IntInsnNode;
import org.objectweb.asm.tree.LdcInsnNode;
import org.objectweb.asm.tree.MethodInsnNode;
import org.objectweb.asm.tree.MethodNode;
import org.objectweb.asm.tree.TypeInsnNode;

/**
 * Initially prepares the method access or accessStatic as follows: <br/><br/>
 * <code>
 * int memberId = TeamManager.getMemberId(accessId, caller);<br/>
 * switch (memberId) {<br/>
 * default:<br/>
 *     return super.access(accessId, opKind, args, caller);<br/> 
 * }<br/>
 * </code>
 * @author Oliver Frank
 */
public class CreateSwitchForAccessAdapter extends CreateSwitchAdapter {

    private String superClassName;
    private AbstractBoundClass clazz;

    public CreateSwitchForAccessAdapter(Method method, String superClassName, AbstractBoundClass clazz) {
        super(method);
        this.superClassName = superClassName;
        this.clazz = clazz;
    }

    @Override
    protected void addPreSwitchInstructions(MethodNode method) {
        // put "accessId" on the stack
        method.instructions.add(new IntInsnNode(Opcodes.ILOAD, getFirstArgIndex()));
        // put "caller".getClass() on the stack
        method.instructions.add(new IntInsnNode(Opcodes.ALOAD, getFirstArgIndex() + 3));
        method.instructions.add(new MethodInsnNode(Opcodes.INVOKEVIRTUAL, "java/lang/Object", "getClass",
                "()Ljava/lang/Class;", false));
        // call "getMemberId(accessId, callerClass)
        method.instructions.add(new MethodInsnNode(Opcodes.INVOKESTATIC, ClassNames.TEAM_MANAGER_SLASH,
                ConstantMembers.getMemberId.getName(), ConstantMembers.getMemberId.getSignature(), false));
    }

    @Override
    protected void addInstructionForDefaultLabel(MethodNode method) {
        if (superClassName.equals("java/lang/Object")) {
            method.instructions.add(new TypeInsnNode(Opcodes.NEW, "org/objectteams/NoSuchMethodError"));
            method.instructions.add(new InsnNode(Opcodes.DUP));
            method.instructions.add(new IntInsnNode(Opcodes.ILOAD, getFirstArgIndex())); // accessId
            method.instructions.add(new LdcInsnNode(clazz.getName())); // current class
            method.instructions.add(new LdcInsnNode("decapsulating access")); // access reason
            method.instructions.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, "org/objectteams/NoSuchMethodError",
                    "<init>", "(ILjava/lang/String;Ljava/lang/String;)V", false));
            method.instructions.add(new InsnNode(Opcodes.ATHROW));
        } else {
            Type[] args = Type.getArgumentTypes(method.desc);
            addInstructionsForLoadArguments(method.instructions, args, getMethod().isStatic());

            int opcode = Opcodes.INVOKESPECIAL;
            if (getMethod().isStatic()) {
                opcode = Opcodes.INVOKESTATIC;
            }
            method.instructions.add(
                    new MethodInsnNode(opcode, superClassName, getMethod().getName(), getMethod().getSignature()));
            method.instructions.add(new InsnNode(Opcodes.ARETURN));
        }
    }

    @Override
    protected int getMaxStack() {
        return 5;
    }

}