dom/mdsal-dom-broker/src/main/java/org/opendaylight/mdsal/dom/broker/PingPongDataBroker.java

   1 /*
   2  * Copyright (c) 2014 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.mdsal.dom.broker;
   9
  10 import org.opendaylight.mdsal.dom.spi.ForwardingDOMDataBroker;
  11
  12 import org.opendaylight.mdsal.common.api.TransactionChainListener;
  13 import org.opendaylight.mdsal.dom.api.DOMDataBroker;
  14 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeListener;
  15 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeService;
  16 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  17 import com.google.common.base.Preconditions;
  18 import javax.annotation.Nonnull;
  19 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  20
  21 /**
  22  * An implementation of a {@link DOMDataBroker}, which forwards most requests to a delegate.
  23  *
  24  * Its interpretation of the API contract is somewhat looser, specifically it does not
  25  * guarantee transaction ordering between transactions allocated directly from the broker
  26  * and its transaction chains.
  27  */
  28 public final class PingPongDataBroker extends ForwardingDOMDataBroker implements AutoCloseable, DOMDataTreeChangeService {
  29     private final DOMDataBroker delegate;
  30
  31     /**
  32      * Instantiate a new broker, backed by the the specified delegate
  33      * {@link DOMDataBroker}.
  34      *
  35      * @param delegate Backend broker, may not be null.
  36      */
  37     public PingPongDataBroker(@Nonnull final DOMDataBroker delegate) {
  38         this.delegate = Preconditions.checkNotNull(delegate);
  39     }
  40
  41     @Override
  42     protected DOMDataBroker delegate() {
  43         return delegate;
  44     }
  45
  46     @Override
  47     public PingPongTransactionChain createTransactionChain(final TransactionChainListener listener) {
  48         return new PingPongTransactionChain(delegate, listener);
  49     }
  50
  51     @Override
  52     public void close() {
  53         // TODO Auto-generated method stub
  54     }
  55
  56     @Override
  57     public <L extends DOMDataTreeChangeListener> ListenerRegistration<L> registerDataTreeChangeListener(final DOMDataTreeIdentifier treeId, final L listener) {
  58         final DOMDataTreeChangeService treeService =
  59                 (DOMDataTreeChangeService) delegate.getSupportedExtensions().get(DOMDataTreeChangeService.class);
  60         if(treeService != null) {
  61             return treeService.registerDataTreeChangeListener(treeId, listener);
  62         }
  63         throw new UnsupportedOperationException("Delegate " + delegate + " does not support required functionality");
  64     }
  65 }