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.util.Map;
020import java.util.concurrent.ConcurrentHashMap;
021
022/**
023 * This repository is used in situations where a Class is created outside the realm of a ClassLoader. Classes are loaded
024 * from the file systems using the paths specified in the given class path. By default, this is the value returned by
025 * ClassPath.getClassPath().
026 * <p>
027 * This repository uses a factory design, allowing it to maintain a collection of different classpaths, and as such It
028 * is designed to be used as a singleton per classpath.
029 * </p>
030 *
031 * @see org.apache.bcel.Repository
032 */
033public class SyntheticRepository extends MemorySensitiveClassPathRepository {
034
035    private static final Map<ClassPath, SyntheticRepository> MAP = new ConcurrentHashMap<>(); // CLASSPATH X REPOSITORY
036
037    public static SyntheticRepository getInstance() {
038        return getInstance(ClassPath.SYSTEM_CLASS_PATH);
039    }
040
041    public static SyntheticRepository getInstance(final ClassPath classPath) {
042        return MAP.computeIfAbsent(classPath, SyntheticRepository::new);
043    }
044
045    private SyntheticRepository(final ClassPath path) {
046        super(path);
047    }
048}