com.sun.enterprise.admin.util.JarFileUtils Maven / Gradle / Ivy

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/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2015-2018 Payara Foundation and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://github.com/payara/Payara/blob/master/LICENSE.txt
 * See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * The Payara Foundation designates this particular file as subject to the "Classpath"
 * exception as provided by the Payara Foundation in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
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package com.sun.enterprise.admin.util;

import java.io.IOException;
import java.lang.reflect.Field;
import java.net.URL;
import java.util.ConcurrentModificationException;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.jar.JarFile;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Utilities class for JarFiles
 *
 * @author Sven Diedrichsen
 * @since 13.06.18
 */
public class JarFileUtils {

    private static final Logger LOG = Logger.getLogger(JarFileUtils.class.getName());

    /**
     * Ensures that all cached JarFile instances are closed.
     */
    public static void closeCachedJarFiles() {
        try {
            Map files = null;
            Object jarFileFactoryInstance = null;
            Class clazz = Class.forName("sun.net.www.protocol.jar.JarFileFactory", true, URL.class.getClassLoader());
            Field fields[] = clazz.getDeclaredFields();
            for (Field field : fields) {
                if ("fileCache".equals(field.getName())) {
                    field.setAccessible(true);
                    files = (Map) field.get(null);
                }
                if ("instance".equals(field.getName())) {
                    field.setAccessible(true);
                    jarFileFactoryInstance = field.get(null);
                }
            }
            if (files != null && !files.isEmpty()) {
                Set jarFiles = new HashSet<>();
                if(jarFileFactoryInstance != null) {
                    synchronized (jarFileFactoryInstance) {
                        jarFiles.addAll(files.values());
                    }
                } else {
                    jarFiles.addAll(files.values());
                }
                for (JarFile file : jarFiles) {
                    if (file != null) {
                        file.close();
                    }
                }
            }
        } catch (ClassNotFoundException | IllegalAccessException | SecurityException | IllegalArgumentException | IOException | ConcurrentModificationException ex) {
            LOG.log(Level.SEVERE, null, ex);
        }
    }

}