org.htmlunit.corejs.javascript.commonjs.module.provider.SoftCachingModuleScriptProvider Maven / Gradle / Ivy

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package org.htmlunit.corejs.javascript.commonjs.module.provider;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.SoftReference;
import java.net.URI;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import org.htmlunit.corejs.javascript.Context;
import org.htmlunit.corejs.javascript.Script;
import org.htmlunit.corejs.javascript.Scriptable;
import org.htmlunit.corejs.javascript.commonjs.module.ModuleScript;

/**
 * A module script provider that uses a module source provider to load modules and caches the loaded
 * modules. It softly references the loaded modules' Rhino {@link Script} objects, thus a module
 * once loaded can become eligible for garbage collection if it is otherwise unused under memory
 * pressure. Instances of this class are thread safe.
 *
 * @author Attila Szegedi
 * @version $Id: SoftCachingModuleScriptProvider.java,v 1.3 2011/04/07 20:26:12 hannes%helma.at Exp
 *     $
 */
public class SoftCachingModuleScriptProvider extends CachingModuleScriptProviderBase {
    private static final long serialVersionUID = 1L;
    private transient ReferenceQueue