    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.util;
    020
    021import java.util.Map;
    022import java.util.concurrent.ConcurrentHashMap;
    023
    024/**
    025 * This repository is used in situations where a Class is created outside the realm of a ClassLoader. Classes are loaded
    026 * from the file systems using the paths specified in the given class path. By default, this is the value returned by
    027 * ClassPath.getClassPath().
    028 * <p>
    029 * This repository uses a factory design, allowing it to maintain a collection of different classpaths, and as such It
    030 * is designed to be used as a singleton per classpath.
    031 * </p>
    032 *
    033 * @see org.apache.bcel.Repository
    034 */
    035public class SyntheticRepository extends MemorySensitiveClassPathRepository {
    036
    037    private static final Map<ClassPath, SyntheticRepository> MAP = new ConcurrentHashMap<>(); // CLASSPATH X REPOSITORY
    038
    039    public static SyntheticRepository getInstance() {
    040        return getInstance(ClassPath.SYSTEM_CLASS_PATH);
    041    }
    042
    043    public static SyntheticRepository getInstance(final ClassPath classPath) {
    044        return MAP.computeIfAbsent(classPath, SyntheticRepository::new);
    045    }
    046
    047    private SyntheticRepository(final ClassPath path) {
    048        super(path);
    049    }
    050}