openstack/sfc-translator/impl/src/main/java/org/opendaylight/netvirt/openstack/sfc/translator/DelegatingDataTreeListener.java

   1 /*
   2  * Copyright (c) 2013, 2016 Dell, 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.openstack.sfc.translator;
  10
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  13 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
  14 import org.opendaylight.controller.md.sal.binding.api.DataObjectModification;
  15 import org.opendaylight.controller.md.sal.binding.api.DataTreeChangeListener;
  16 import org.opendaylight.controller.md.sal.binding.api.DataTreeIdentifier;
  17 import org.opendaylight.controller.md.sal.binding.api.DataTreeModification;
  18 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  19 import org.opendaylight.yangtools.yang.binding.DataObject;
  20 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  21 import org.slf4j.Logger;
  22 import org.slf4j.LoggerFactory;
  23
  24 import javax.annotation.Nonnull;
  25 import java.util.Collection;
  26 import java.util.concurrent.ExecutorService;
  27 import java.util.concurrent.Executors;
  28 import java.util.concurrent.ThreadFactory;
  29
  30 /**
  31  * Data-tree listener which delegates data processing to a {@link INeutronSfcDataProcessor}.
  32  */
  33 public abstract class DelegatingDataTreeListener<T extends DataObject> implements AutoCloseable,
  34         DataTreeChangeListener<T>,
  35         INeutronSfcDataProcessor<T> {
  36     private static final Logger LOG = LoggerFactory.getLogger(DelegatingDataTreeListener.class);
  37     private static final ThreadFactory threadFactory = new ThreadFactoryBuilder()
  38         .setNameFormat("NeutronSfcListener-%d").build();
  39     private final ExecutorService executorService = Executors.newFixedThreadPool(1, threadFactory);
  40     private final INeutronSfcDataProcessor<T> dataProcessor;
  41     private ListenerRegistration<DelegatingDataTreeListener<T>> listenerRegistration;
  42
  43     public DelegatingDataTreeListener(DataBroker db, DataTreeIdentifier<T> treeId) {
  44         this.dataProcessor = Preconditions.checkNotNull(this, "Data processor can not be null!");
  45         registerListener(Preconditions.checkNotNull(db, "Data broker can not be null!"),
  46                 Preconditions.checkNotNull(treeId, "Tree identifier can not be null!"));
  47     }
  48
  49     private void registerListener(final DataBroker db, DataTreeIdentifier<T> treeId) {
  50         try {
  51             LOG.info("Registering Data Change Listener for {}", getClass().getSimpleName());
  52             listenerRegistration = db.registerDataTreeChangeListener(treeId, this);
  53         } catch (final Exception e) {
  54             LOG.warn("{} DataChange listener registration fail!", getClass().getSimpleName(), e);
  55             throw new IllegalStateException("DataTreeListener startup fail! System needs restart.", e);
  56         }
  57     }
  58
  59     private void processChanges(Collection<DataTreeModification<T>> changes) {
  60         LOG.info("onDataTreeChanged: Received Data Tree Changed {}", changes);
  61         for (DataTreeModification<T> change : changes) {
  62             final InstanceIdentifier<T> key = change.getRootPath().getRootIdentifier();
  63             final DataObjectModification<T> mod = change.getRootNode();
  64             LOG.info("onDataTreeChanged: Received Data Tree Changed Update of Type={} for Key={}",
  65                     mod.getModificationType(), key);
  66             switch (mod.getModificationType()) {
  67                 case DELETE:
  68                     dataProcessor.remove(key, mod.getDataBefore());
  69                     break;
  70                 case SUBTREE_MODIFIED:
  71                     dataProcessor.update(key, mod.getDataBefore(), mod.getDataAfter());
  72                     break;
  73                 case WRITE:
  74                     if (mod.getDataBefore() == null) {
  75                         dataProcessor.add(key, mod.getDataAfter());
  76                     } else {
  77                         dataProcessor.update(key, mod.getDataBefore(), mod.getDataAfter());
  78                     }
  79                     break;
  80                 default:
  81                     throw new IllegalArgumentException("Unhandled modification type " + mod.getModificationType());
  82             }
  83         }
  84     }
  85
  86     @Override
  87     public void onDataTreeChanged(@Nonnull final Collection<DataTreeModification<T>> changes) {
  88         Preconditions.checkNotNull(changes, "Changes may not be null!");
  89         executorService.submit(new Runnable() {
  90             @Override
  91             public void run() {
  92                 processChanges(changes);
  93             }
  94         });
  95     }
  96
  97     @Override
  98     public void close() {
  99         if (listenerRegistration != null) {
 100             listenerRegistration.close();
 101             listenerRegistration = null;
 102         }
 103         if (executorService != null) {
 104             executorService.shutdownNow();
 105         }
 106     }
 107 }