openflowplugin-impl/src/main/java/org/opendaylight/openflowplugin/impl/connection/OutboundQueueProviderImpl.java

   1 /*
   2  * Copyright (c) 2015 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
   9 package org.opendaylight.openflowplugin.impl.connection;
  10
  11 import com.google.common.util.concurrent.FutureCallback;
  12 import javax.annotation.Nonnull;
  13 import org.opendaylight.openflowjava.protocol.api.connection.OutboundQueue;
  14 import org.opendaylight.openflowplugin.api.openflow.connection.OutboundQueueProvider;
  15 import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.protocol.rev130731.BarrierInput;
  16 import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.protocol.rev130731.BarrierInputBuilder;
  17 import org.opendaylight.yang.gen.v1.urn.opendaylight.openflow.protocol.rev130731.OfHeader;
  18 import org.slf4j.Logger;
  19 import org.slf4j.LoggerFactory;
  20
  21 public class OutboundQueueProviderImpl implements OutboundQueueProvider {
  22     private static final Logger LOG = LoggerFactory.getLogger(OutboundQueueProviderImpl.class);
  23     private final short ofVersion;
  24     private volatile OutboundQueue outboundQueue;
  25
  26     public OutboundQueueProviderImpl(final short ofVersion) {
  27         this.ofVersion = ofVersion;
  28     }
  29
  30     @Nonnull
  31     @Override
  32     public BarrierInput createBarrierRequest(@Nonnull final Long xid) {
  33         final BarrierInputBuilder biBuilder = new BarrierInputBuilder();
  34         biBuilder.setVersion(ofVersion);
  35         biBuilder.setXid(xid);
  36         return biBuilder.build();
  37
  38     }
  39
  40     @Override
  41     public synchronized void onConnectionQueueChanged(final OutboundQueue queue) {
  42         LOG.debug("Replacing queue {} with {}", outboundQueue, queue);
  43         outboundQueue = queue;
  44         notifyAll();
  45     }
  46
  47     @Override
  48     public Long reserveEntry() {
  49         for (;;) {
  50             OutboundQueue queue = outboundQueue;
  51             if (queue == null) {
  52                 LOG.error("No queue present, failing request");
  53                 return null;
  54             }
  55
  56             final Long ret = queue.reserveEntry();
  57             if (ret != null) {
  58                 return ret;
  59             }
  60
  61             LOG.debug("Reservation failed, trying to recover");
  62             synchronized (this) {
  63                 while (queue.equals(outboundQueue)) {
  64                     LOG.debug("Queue {} is not replaced yet, going to sleep", queue);
  65                     try {
  66                         wait();
  67                     } catch (InterruptedException e) {
  68                         LOG.error("Interrupted while waiting for entry", e);
  69                         return null;
  70                     }
  71                 }
  72             }
  73         }
  74     }
  75
  76     @Override
  77     public void commitEntry(final Long xid, final OfHeader message, final FutureCallback<OfHeader> callback) {
  78         outboundQueue.commitEntry(xid, message, callback);
  79     }
  80 }