001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.bcel.verifier;
020
021import org.apache.bcel.Repository;
022import org.apache.bcel.classfile.JavaClass;
023import org.apache.bcel.classfile.Utility;
024
025/**
026 * This class has a main method implementing a demonstration program of how to use the VerifierFactoryObserver. It
027 * transitively verifies all class files encountered; this may take up a lot of time and, more notably, memory.
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     * @param args command line arguments (expects one argument: the root class to verify).
036     */
037    public static void main(final String[] args) {
038        if (args.length != 1) {
039            System.out.println("Need exactly one argument: The root class to verify.");
040            System.exit(1);
041        }
042        final int dotclasspos = args[0].lastIndexOf(JavaClass.EXTENSION);
043        if (dotclasspos != -1) {
044            args[0] = args[0].substring(0, dotclasspos);
045        }
046        args[0] = Utility.pathToPackage(args[0]);
047        final TransitiveHull th = new TransitiveHull();
048        VerifierFactory.attach(th);
049        VerifierFactory.getVerifier(args[0]); // the observer is called back and does the actual trick.
050        VerifierFactory.detach(th);
051    }
052
053    /** Used for indentation. */
054    private int indent;
055
056    /** Not publicly instantiable. */
057    private TransitiveHull() {
058    }
059
060    /* Implementing VerifierFactoryObserver. */
061    @Override
062    public void update(final String className) {
063        System.gc(); // avoid swapping if possible.
064        for (int i = 0; i < indent; i++) {
065            System.out.print(" ");
066        }
067        System.out.println(className);
068        indent += 1;
069        final Verifier v = VerifierFactory.getVerifier(className);
070        VerificationResult vr;
071        vr = v.doPass1();
072        if (vr != VerificationResult.VR_OK) {
073            System.out.println("Pass 1:\n" + vr);
074        }
075        vr = v.doPass2();
076        if (vr != VerificationResult.VR_OK) {
077            System.out.println("Pass 2:\n" + vr);
078        }
079        if (vr == VerificationResult.VR_OK) {
080            try {
081                final JavaClass jc = Repository.lookupClass(v.getClassName());
082                for (int i = 0; i < jc.getMethods().length; i++) {
083                    vr = v.doPass3a(i);
084                    if (vr != VerificationResult.VR_OK) {
085                        System.out.println(v.getClassName() + ", Pass 3a, method " + i + " ['" + jc.getMethods()[i] + "']:\n" + vr);
086                    }
087                    vr = v.doPass3b(i);
088                    if (vr != VerificationResult.VR_OK) {
089                        System.out.println(v.getClassName() + ", Pass 3b, method " + i + " ['" + jc.getMethods()[i] + "']:\n" + vr);
090                    }
091                }
092            } catch (final ClassNotFoundException e) {
093                System.err.println("Could not find class " + v.getClassName() + " in Repository");
094            }
095        }
096        indent -= 1;
097    }
098}