com.google.singletondetector.visitors.SingletonClassVisitor.java Source code

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Here is the source code for com.google.singletondetector.visitors.SingletonClassVisitor.java

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/*
 * Copyright 2007 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.singletondetector.visitors;

import com.google.singletondetector.SingletonDetector;

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

/**
 * Visitor object that is responsible for traversing a class and noting static
 * fields and static method calls. Helps SingletonDetector figure out which
 * classes are special and what type of special class they are.
 * 
 * @author David Rubel
 */
public class SingletonClassVisitor extends NoopClassVisitor {
    // Reference to the singleton detector, used to call visit methods
    SingletonDetector sd;

    public SingletonClassVisitor(SingletonDetector sd) {
        super();
        this.sd = sd;
    }

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

    @Override
    public FieldVisitor visitField(int access, String name, String desc, String signature, Object value) {
        if ((access & Opcodes.ACC_STATIC) == Opcodes.ACC_STATIC) {
            if ((access & Opcodes.ACC_PUBLIC) == Opcodes.ACC_PUBLIC) {
                sd.visitStaticField(name, desc);
            }

            if ((access & Opcodes.ACC_PRIVATE) == Opcodes.ACC_PRIVATE
                    && (access & Opcodes.ACC_FINAL) != Opcodes.ACC_FINAL) {
                sd.addStaticField(name, desc);
            }
        }
        return null;
    }

    @Override
    public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
        if (((access & Opcodes.ACC_STATIC) == Opcodes.ACC_STATIC
                && (access & Opcodes.ACC_PUBLIC) == Opcodes.ACC_PUBLIC)) {
            sd.visitStaticMethod(name, desc);
        }

        return super.visitMethod(access, name, desc, signature, exceptions);
    }

    @Override
    public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
        return null;
    }
}