com.google.devtools.build.wireless.testing.java.injector.WhiteBoxClassAdapter.java Source code

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Here is the source code for com.google.devtools.build.wireless.testing.java.injector.WhiteBoxClassAdapter.java

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/* Copyright 2008 Google Inc.
 * 
 * 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.google.devtools.build.wireless.testing.java.injector;

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

import java.util.logging.Logger;

/**
 * ClassAdapter which exposes all the call to methods and fields-access to 
 * objects. Only objects matching a specific pattern are injected and inside 
 * those only specific methods/field are exposed according to a set of regular 
 * expressions.
 * 
 * @author Michele Sama
 * 
 */
public class WhiteBoxClassAdapter extends ClassAdapter {

    protected Platform targetPlatform;

    /**
     * The regular expression containing the class inclusion.
     */
    protected String classInclusionPattern = null;

    /**
     * The regular expression which specify method inclusion.
     */
    protected String methodInclusionPattern = null;

    /**
     * The regular expression which specify field inclusion.
     */
    protected String fieldInclusionPattern = null;

    protected String currentClass;

    protected boolean isInterface;

    protected static Logger logger = Logger.getLogger("WhiteBoxClassAdapter");

    /**
     * Creates a white box class adapter which will delegate a white box method 
     * adapter for visiting each method.
     * 
     * TODO: this is going to be changed ass soon a selector will be 
     *    implemented.
     * 
     * @param cv The nested ClassVisitor.
     * @param classInclusion A String containing class inclusion.
     * @param methodInclusion A String containing method inclusion.
     * @param fieldInclusion A String containing field inclusion.
     * @param platform The target {@link Platform}.
     */
    public WhiteBoxClassAdapter(ClassVisitor cv, String classInclusion, String methodInclusion,
            String fieldInclusion, Platform platform) {
        super(cv);
        targetPlatform = platform;
        classInclusionPattern = classInclusion;
        methodInclusionPattern = methodInclusion;
        fieldInclusionPattern = fieldInclusion;
    }

    /**
     * Visits a class and stores a flag saying if it is an interface.
     */
    @Override
    public void visit(int version, int access, String name, String signature, String superName,
            String[] interfaces) {
        cv.visit(version, access, name, signature, superName, interfaces);
        currentClass = name;
        isInterface = (access & Opcodes.ACC_INTERFACE) != 0;
    }

    /**
     * Creates and returns a white box method adapter is the current class is not 
     * an interface and is the method is not toString, because toString is 
     * currently used by the white box and instrumenting it would create a loop.
     */
    @Override
    public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
        MethodVisitor mv = cv.visitMethod(access, name, desc, signature, exceptions);
        if (!isInterface && mv != null && !name.equals("toString")) {
            mv = new WhiteBoxMethodAdapter(mv, access, currentClass, name, desc, classInclusionPattern,
                    methodInclusionPattern, fieldInclusionPattern, targetPlatform);
        }
        return mv;
    }

}