Glassfish example source code file (JDBCExtender.java)

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Java - Glassfish tags/keywords

bundleevent, bundleevent, bundletracker, classloader, datasourcefactoryimpl, habitat, jdbcbundletrackercustomizer, jdbcextender, log, logging, object, object, properties, properties, string, string, util

The Glassfish JDBCExtender.java source code

/*
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 *
 * Copyright (c) 2009-2010 Oracle and/or its affiliates. All rights reserved.
 *
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 * 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
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package org.glassfish.osgijdbc;

import org.glassfish.internal.api.ClassLoaderHierarchy;
import org.glassfish.internal.api.Globals;
import org.glassfish.osgijavaeebase.Extender;
import org.jvnet.hk2.component.Habitat;
import org.osgi.framework.*;
import org.osgi.service.jdbc.DataSourceFactory;
import org.osgi.service.url.URLConstants;
import org.osgi.service.url.URLStreamHandlerService;
import org.osgi.util.tracker.BundleTracker;
import org.osgi.util.tracker.BundleTrackerCustomizer;

import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;

public class JDBCExtender implements Extender {

    private BundleContext bundleContext;

    private ServiceRegistration urlHandlerService;

    private Set<DataSourceFactoryImpl> dataSourceFactories = new HashSet();
    private Habitat habitat;

    private BundleTracker bundleTracker;

    private static final Logger logger = Logger.getLogger(
            JDBCExtender.class.getPackage().getName());

    public JDBCExtender(BundleContext context) {
        this.bundleContext = context;
    }

    public void start() {
        debug("begin start()");
        habitat = Globals.getDefaultHabitat();
        bundleTracker = new BundleTracker(bundleContext, Bundle.ACTIVE, new JDBCBundleTrackerCustomizer());
        bundleTracker.open();
        addURLHandler();
        debug("completed start()");
    }

    public void stop() {
        removeURLHandler();
        if (bundleTracker != null) {
            bundleTracker.close();
        }
        for (DataSourceFactoryImpl dsfi : dataSourceFactories) {
            dsfi.preDestroy();
        }
        debug("stopped");
    }

    private Habitat getHabitat(){
        return habitat;
    }

    private void addURLHandler() {

        //create parent class-loader (API ClassLoader to access Java EE API)
        ClassLoaderHierarchy clh = getHabitat().getByContract(ClassLoaderHierarchy.class);
        ClassLoader apiClassLoader = clh.getAPIClassLoader();

        Properties p = new Properties();
        p.put(URLConstants.URL_HANDLER_PROTOCOL, new String[]{Constants.JDBC_DRIVER_SCHEME});
        urlHandlerService = bundleContext.registerService(URLStreamHandlerService.class.getName(),
                new JDBCDriverURLStreamHandlerService(apiClassLoader), p);
    }

    private void removeURLHandler() {
        if (urlHandlerService != null) {
            urlHandlerService.unregister();
            urlHandlerService = null;
        }
    }

    private boolean isJdbcDriverBundle(Bundle b) {
        String osgiRFC = (String) b.getHeaders().get(Constants.OSGI_RFC_122);
        if (osgiRFC != null && Boolean.valueOf(osgiRFC)) {
            return true;
        } else {
            return false;
        }
    }

    private void debug(String s) {
        if(logger.isLoggable(Level.FINEST)){
            logger.finest("[osgi-jdbc] : " + s);
        }
    }

    private class JDBCBundleTrackerCustomizer implements BundleTrackerCustomizer {
        public Object addingBundle(Bundle bundle, BundleEvent event) {
            if (isJdbcDriverBundle(bundle)) {
                debug("Starting JDBC Bundle : " + bundle.getSymbolicName());

                DataSourceFactoryImpl dsfi = new DataSourceFactoryImpl(bundle.getBundleContext());
                dataSourceFactories.add(dsfi);

                Properties serviceProperties = new Properties();
                Dictionary header = bundle.getHeaders();
                serviceProperties.put(DataSourceFactory.OSGI_JDBC_DRIVER_CLASS,
                        header.get(Constants.DRIVER.replace(".", "_")));

                String implVersion = (String) header.get(Constants.IMPL_VERSION);
                if (implVersion != null) {
                    serviceProperties.put(DataSourceFactory.OSGI_JDBC_DRIVER_VERSION, implVersion);
                }

                String implTitle = (String) header.get(Constants.IMPL_TITLE);
                if (implTitle != null) {
                    serviceProperties.put(DataSourceFactory.OSGI_JDBC_DRIVER_NAME, implTitle);
                }
                debug(" registering service for driver [" +
                        header.get(Constants.DRIVER.replace(".", "_")) + "]");
                bundle.getBundleContext().registerService(DataSourceFactory.class.getName(),
                        dsfi, serviceProperties);
            }
            return null; // no need to track this any more
        }

        public void modifiedBundle(Bundle bundle, BundleEvent event, Object object) {
        }

        public void removedBundle(Bundle bundle, BundleEvent event, Object object) {
        }
    }
}