    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 */
    017package org.apache.bcel.util;
    018
    019import java.io.IOException;
    020import java.io.InputStream;
    021import java.util.HashMap;
    022import java.util.Map;
    023
    024import org.apache.bcel.classfile.ClassParser;
    025import org.apache.bcel.classfile.JavaClass;
    026import org.apache.bcel.classfile.Utility;
    027
    028/**
    029 * The repository maintains information about which classes have been loaded.
    030 *
    031 * It loads its data from the ClassLoader implementation passed into its constructor.
    032 *
    033 * @see org.apache.bcel.Repository
    034 */
    035public class ClassLoaderRepository implements Repository {
    036
    037    private final java.lang.ClassLoader loader;
    038    private final Map<String, JavaClass> loadedClasses = new HashMap<>(); // CLASSNAME X JAVACLASS
    039
    040    public ClassLoaderRepository(final java.lang.ClassLoader loader) {
    041        this.loader = loader;
    042    }
    043
    044    /**
    045     * Clear all entries from cache.
    046     */
    047    @Override
    048    public void clear() {
    049        loadedClasses.clear();
    050    }
    051
    052    /**
    053     * Find an already defined JavaClass.
    054     */
    055    @Override
    056    public JavaClass findClass(final String className) {
    057        return loadedClasses.get(className);
    058    }
    059
    060    /*
    061     * @return null
    062     */
    063    @Override
    064    public ClassPath getClassPath() {
    065        return null;
    066    }
    067
    068    @Override
    069    public JavaClass loadClass(final Class<?> clazz) throws ClassNotFoundException {
    070        return loadClass(clazz.getName());
    071    }
    072
    073    /**
    074     * Lookup a JavaClass object from the Class Name provided.
    075     */
    076    @Override
    077    public JavaClass loadClass(final String className) throws ClassNotFoundException {
    078        final String classFile = Utility.packageToPath(className);
    079        JavaClass RC = findClass(className);
    080        if (RC != null) {
    081            return RC;
    082        }
    083        try (InputStream is = loader.getResourceAsStream(classFile + JavaClass.EXTENSION)) {
    084            if (is == null) {
    085                throw new ClassNotFoundException(className + " not found.");
    086            }
    087            final ClassParser parser = new ClassParser(is, className);
    088            RC = parser.parse();
    089            storeClass(RC);
    090            return RC;
    091        } catch (final IOException e) {
    092            throw new ClassNotFoundException(className + " not found: " + e, e);
    093        }
    094    }
    095
    096    /**
    097     * Remove class from repository
    098     */
    099    @Override
    100    public void removeClass(final JavaClass clazz) {
    101        loadedClasses.remove(clazz.getClassName());
    102    }
    103
    104    /**
    105     * Store a new JavaClass into this Repository.
    106     */
    107    @Override
    108    public void storeClass(final JavaClass clazz) {
    109        loadedClasses.put(clazz.getClassName(), clazz);
    110        clazz.setRepository(this);
    111    }
    112}