opendaylight/config/config-manager/src/main/java/org/opendaylight/controller/config/manager/impl/osgi/ExtensibleBundleTracker.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.config.manager.impl.osgi;
   9
  10 import org.osgi.framework.Bundle;
  11 import org.osgi.framework.BundleContext;
  12 import org.osgi.framework.BundleEvent;
  13 import org.osgi.util.tracker.BundleTracker;
  14 import org.osgi.util.tracker.BundleTrackerCustomizer;
  15 import org.slf4j.Logger;
  16 import org.slf4j.LoggerFactory;
  17
  18 /**
  19  *
  20  * Extensible bundle tracker. Takes several BundleTrackerCustomizers and propagates bundle events to all of them.
  21  * Primary customizer
  22  *
  23  * @param <T>
  24  */
  25 public final class ExtensibleBundleTracker<T> extends BundleTracker<T> {
  26
  27     private final BundleTrackerCustomizer<T> primaryTracker;
  28     private final BundleTrackerCustomizer<?>[] additionalTrackers;
  29
  30     private static final Logger logger = LoggerFactory.getLogger(ExtensibleBundleTracker.class);
  31
  32     public ExtensibleBundleTracker(BundleContext context, BundleTrackerCustomizer<T> primaryBundleTrackerCustomizer,
  33                                    BundleTrackerCustomizer<?>... additionalBundleTrackerCustomizers) {
  34         this(context, Bundle.ACTIVE, primaryBundleTrackerCustomizer, additionalBundleTrackerCustomizers);
  35     }
  36
  37     public ExtensibleBundleTracker(BundleContext context, int bundleState,
  38                                    BundleTrackerCustomizer<T> primaryBundleTrackerCustomizer,
  39                                    BundleTrackerCustomizer<?>... additionalBundleTrackerCustomizers) {
  40         super(context, bundleState, null);
  41         this.primaryTracker = primaryBundleTrackerCustomizer;
  42         this.additionalTrackers = additionalBundleTrackerCustomizers;
  43         logger.trace("Registered as extender with context {} and bundle state {}", context, bundleState);
  44     }
  45
  46     @Override
  47     public T addingBundle(final Bundle bundle, final BundleEvent event) {
  48         T primaryTrackerRetVal = primaryTracker.addingBundle(bundle, event);
  49
  50         forEachAdditionalBundle(new BundleStrategy() {
  51             @Override
  52             public void execute(BundleTrackerCustomizer<?> tracker) {
  53                 tracker.addingBundle(bundle, event);
  54             }
  55         });
  56
  57         return primaryTrackerRetVal;
  58     }
  59
  60     @Override
  61     public void modifiedBundle(final Bundle bundle, final BundleEvent event, final T object) {
  62         primaryTracker.modifiedBundle(bundle, event, object);
  63
  64         forEachAdditionalBundle(new BundleStrategy() {
  65             @Override
  66             public void execute(BundleTrackerCustomizer<?> tracker) {
  67                 tracker.modifiedBundle(bundle, event, null);
  68             }
  69         });
  70
  71     }
  72
  73     @Override
  74     public void removedBundle(final Bundle bundle, final BundleEvent event, final T object) {
  75         primaryTracker.removedBundle(bundle, event, object);
  76
  77         forEachAdditionalBundle(new BundleStrategy() {
  78             @Override
  79             public void execute(BundleTrackerCustomizer<?> tracker) {
  80                 tracker.removedBundle(bundle, event, null);
  81             }
  82         });
  83     }
  84
  85     private void forEachAdditionalBundle(BundleStrategy lambda) {
  86         for (BundleTrackerCustomizer<?> trac : additionalTrackers) {
  87             lambda.execute(trac);
  88         }
  89     }
  90
  91     private static interface BundleStrategy {
  92         void execute(BundleTrackerCustomizer<?> tracker);
  93     }
  94
  95 }