netvirt/renderers/neutron/src/main/java/org/opendaylight/netvirt/netvirt/renderers/neutron/DelegatingDataTreeListener.java

   1 /*
   2  * Copyright (c) 2013, 2016 Red Hat, 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
   9 package org.opendaylight.netvirt.netvirt.renderers.neutron;
  10
  11 import com.google.common.base.Preconditions;
  12 import java.util.Collection;
  13 import java.util.concurrent.ExecutorService;
  14 import java.util.concurrent.Executors;
  15 import java.util.concurrent.ThreadFactory;
  16 import javax.annotation.Nonnull;
  17
  18 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  19 import org.opendaylight.controller.md.sal.binding.api.*;
  20 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  21 import org.opendaylight.yangtools.yang.binding.DataObject;
  22 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25
  26 /**
  27  * Data-tree listener which delegates data processing to a {@link DataProcessor}.
  28  */
  29 public class DelegatingDataTreeListener<T extends DataObject> implements AutoCloseable, ClusteredDataTreeChangeListener<T> {
  30     private static final Logger LOG = LoggerFactory.getLogger(DelegatingDataTreeListener.class);
  31     protected NeutronProvider provider;
  32     protected DataBroker db;
  33     private static final ThreadFactory threadFactory = new ThreadFactoryBuilder()
  34         .setNameFormat("NV-NeutronDTL-%d").build();
  35     private final ExecutorService executorService = Executors.newFixedThreadPool(1, threadFactory);
  36     private final DataProcessor<T> dataProcessor;
  37     private ListenerRegistration<DelegatingDataTreeListener<T>> listenerRegistration;
  38
  39     public DelegatingDataTreeListener(NeutronProvider provider, DataProcessor<T> dataProcessor,
  40                                       DataBroker db, DataTreeIdentifier<T> treeId) {
  41         this.provider = Preconditions.checkNotNull(provider, "provider can not be null!");
  42         this.dataProcessor = Preconditions.checkNotNull(dataProcessor, "Data processor can not be null!");
  43         registerListener(Preconditions.checkNotNull(db, "Data broker can not be null!"),
  44                 Preconditions.checkNotNull(treeId, "Tree identifier can not be null!"));
  45     }
  46
  47     private void registerListener(final DataBroker db, DataTreeIdentifier<T> treeId) {
  48         try {
  49             LOG.info("Registering Data Change Listener for {}", getClass().getSimpleName());
  50             this.db = db;
  51             listenerRegistration = db.registerDataTreeChangeListener(treeId, this);
  52         } catch (final Exception e) {
  53             LOG.warn("{} DataChange listener registration fail!", getClass().getSimpleName(), e);
  54             throw new IllegalStateException("DataTreeListener startup fail! System needs restart.", e);
  55         }
  56     }
  57
  58     private void processChanges(Collection<DataTreeModification<T>> changes) {
  59         for (DataTreeModification<T> change : changes) {
  60             final InstanceIdentifier<T> key = change.getRootPath().getRootIdentifier();
  61             final DataObjectModification<T> mod = change.getRootNode();
  62             switch (mod.getModificationType()) {
  63                 case DELETE:
  64                     dataProcessor.remove(key, mod.getDataBefore());
  65                     break;
  66                 case SUBTREE_MODIFIED:
  67                     dataProcessor.update(key, mod.getDataBefore(), mod.getDataAfter());
  68                     break;
  69                 case WRITE:
  70                     if (mod.getDataBefore() == null) {
  71                         dataProcessor.add(key, mod.getDataAfter());
  72                     } else {
  73                         dataProcessor.update(key, mod.getDataBefore(), mod.getDataAfter());
  74                     }
  75                     break;
  76                 default:
  77                     throw new IllegalArgumentException("Unhandled modification type " + mod.getModificationType());
  78             }
  79         }
  80     }
  81
  82     @Override
  83     public void onDataTreeChanged(@Nonnull final Collection<DataTreeModification<T>> changes) {
  84         Preconditions.checkNotNull(changes, "Changes may not be null!");
  85         executorService.submit(new Runnable() {
  86             @Override
  87             public void run() {
  88                 processChanges(changes);
  89             }
  90         });
  91     }
  92
  93     @Override
  94     public void close() {
  95         if (listenerRegistration != null) {
  96             listenerRegistration.close();
  97             listenerRegistration = null;
  98         }
  99     }
 100 }