001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 *  Unless required by applicable law or agreed to in writing, software
012 *  distributed under the License is distributed on an "AS IS" BASIS,
013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 *  See the License for the specific language governing permissions and
015 *  limitations under the License.
016 *
017 */
018package org.apache.bcel.verifier;
019
020import org.apache.bcel.Repository;
021import org.apache.bcel.classfile.JavaClass;
022import org.apache.bcel.classfile.Utility;
023
024/**
025 * This class has a main method implementing a demonstration program of how to use the VerifierFactoryObserver. It
026 * transitively verifies all class files encountered; this may take up a lot of time and, more notably, memory.
027 *
028 */
029public class TransitiveHull implements VerifierFactoryObserver {
030
031    /**
032     * This method implements a demonstration program of how to use the VerifierFactoryObserver. It transitively verifies
033     * all class files encountered; this may take up a lot of time and, more notably, memory.
034     */
035    public static void main(final String[] args) {
036        if (args.length != 1) {
037            System.out.println("Need exactly one argument: The root class to verify.");
038            System.exit(1);
039        }
040        final int dotclasspos = args[0].lastIndexOf(".class");
041        if (dotclasspos != -1) {
042            args[0] = args[0].substring(0, dotclasspos);
043        }
044        args[0] = Utility.pathToPackage(args[0]);
045        final TransitiveHull th = new TransitiveHull();
046        VerifierFactory.attach(th);
047        VerifierFactory.getVerifier(args[0]); // the observer is called back and does the actual trick.
048        VerifierFactory.detach(th);
049    }
050
051    /** Used for indentation. */
052    private int indent;
053
054    /** Not publicly instantiable. */
055    private TransitiveHull() {
056    }
057
058    /* Implementing VerifierFactoryObserver. */
059    @Override
060    public void update(final String classname) {
061        System.gc(); // avoid swapping if possible.
062        for (int i = 0; i < indent; i++) {
063            System.out.print(" ");
064        }
065        System.out.println(classname);
066        indent += 1;
067        final Verifier v = VerifierFactory.getVerifier(classname);
068        VerificationResult vr;
069        vr = v.doPass1();
070        if (vr != VerificationResult.VR_OK) {
071            System.out.println("Pass 1:\n" + vr);
072        }
073        vr = v.doPass2();
074        if (vr != VerificationResult.VR_OK) {
075            System.out.println("Pass 2:\n" + vr);
076        }
077        if (vr == VerificationResult.VR_OK) {
078            try {
079                final JavaClass jc = Repository.lookupClass(v.getClassName());
080                for (int i = 0; i < jc.getMethods().length; i++) {
081                    vr = v.doPass3a(i);
082                    if (vr != VerificationResult.VR_OK) {
083                        System.out.println(v.getClassName() + ", Pass 3a, method " + i + " ['" + jc.getMethods()[i] + "']:\n" + vr);
084                    }
085                    vr = v.doPass3b(i);
086                    if (vr != VerificationResult.VR_OK) {
087                        System.out.println(v.getClassName() + ", Pass 3b, method " + i + " ['" + jc.getMethods()[i] + "']:\n" + vr);
088                    }
089                }
090            } catch (final ClassNotFoundException e) {
091                System.err.println("Could not find class " + v.getClassName() + " in Repository");
092            }
093        }
094        indent -= 1;
095    }
096}