Glassfish example source code file (ProbeProviderRegistry.java)

This example Glassfish source code file (ProbeProviderRegistry.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Glassfish tags/keywords

class, collection, concurrenthashmap, concurrentmap, flashlightprobeprovider, flashlightprobeprovider, illegalstateexception, probeproviderregistry, probeproviderregistry, provider, provider, string, string, threading, threads, util

The Glassfish ProbeProviderRegistry.java source code

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 1997-2010 Oracle 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://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/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 packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle 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:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package org.glassfish.flashlight.impl.core;

import java.util.*;
import java.util.concurrent.*;
import org.glassfish.flashlight.FlashlightUtils;

/**
 * @author Mahesh Kannan
 * @author Byron Nevins
 * Date: Jun 25, 2008
 *
 * Byron Nevins says:  Note this class is used in one and only one place in all of
 * GF --> FlashlightProbeProviderFactory.java
 * Apparently it is used exclusively for making sure that 2 probes with the same name are not allowed?!?
 * look at the putIfAbsent for clues
 * This class has no business having any public members and should be moved to the only user's package
 *
 * I'm suspicious.  Maybe it is called by reflection from somewhere?!?
 */
public class ProbeProviderRegistry {
    private ProbeProviderRegistry() {
    }

    public static ProbeProviderRegistry getInstance() {
        return _me;
    }

    public static void cleanup() {
        _me = new ProbeProviderRegistry();    
    }

    public Collection<FlashlightProbeProvider> getAllProbeProviders() {
        return Collections.unmodifiableCollection(providerMap.values());
    }

    public FlashlightProbeProvider getProbeProvider(String moduleProviderName, String moduleName, String probeProviderName) {
        if(probeProviderName == null)
            probeProviderName = "";

        return providerMap.get(FlashlightUtils.makeName(moduleProviderName, moduleName, probeProviderName));
    }

    public FlashlightProbeProvider getProbeProvider(Class clz) {
        return classProviderMap.get(clz);
    }
    
    public FlashlightProbeProvider getProbeProvider(FlashlightProbeProvider fpp) {
        return providerMap.get(FlashlightUtils.makeName(fpp));
    }

    public FlashlightProbeProvider registerProbeProvider(FlashlightProbeProvider provider, Class clz) {

        String qname = FlashlightUtils.makeName(provider);

        // if there is an entry in the map for qname already -- it is an error
        // ConcurrentMap allows us to check and put with thread-safety!
        // putIfAbsent returns null iff there was no value already in there.

        if (providerMap.putIfAbsent(qname, provider) != null) {
            throw new IllegalStateException("Provider already mapped " + qname);
        }

        if (classProviderMap.putIfAbsent(clz, provider) != null) {
            throw new IllegalStateException("Provider already mapped " + qname);
        }

        return provider;
    }

    public void unregisterProbeProvider(Object provider) {
        FlashlightProbeProvider fpp = classProviderMap.remove(provider.getClass());
        String qname = FlashlightUtils.makeName(fpp);
        providerMap.remove(qname);
    }

    private static ProbeProviderRegistry _me =
            new ProbeProviderRegistry();

    private ConcurrentMap<String, FlashlightProbeProvider> providerMap =
            new ConcurrentHashMap<String, FlashlightProbeProvider>();
    private ConcurrentMap<Class, FlashlightProbeProvider> classProviderMap =
            new ConcurrentHashMap<Class, FlashlightProbeProvider>();
}