openflowplugin-impl/src/main/java/org/opendaylight/openflowplugin/impl/util/BarrierUtil.java

   1 /*
   2  * Copyright (c) 2016 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.util;
  10
  11 import com.google.common.base.Function;
  12 import com.google.common.util.concurrent.AsyncFunction;
  13 import com.google.common.util.concurrent.Futures;
  14 import com.google.common.util.concurrent.JdkFutureAdapters;
  15 import com.google.common.util.concurrent.ListenableFuture;
  16 import javax.annotation.Nullable;
  17 import org.apache.commons.lang3.tuple.MutablePair;
  18 import org.apache.commons.lang3.tuple.Pair;
  19 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.transaction.rev150304.FlowCapableTransactionService;
  20 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.transaction.rev150304.SendBarrierInput;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.transaction.rev150304.SendBarrierInputBuilder;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.NodeRef;
  23 import org.opendaylight.yangtools.yang.common.RpcResult;
  24 import org.slf4j.Logger;
  25 import org.slf4j.LoggerFactory;
  26
  27 /**
  28  * provides barrier message chaining and factory methods
  29  */
  30 public final class BarrierUtil {
  31
  32     private static final Logger LOG = LoggerFactory.getLogger(BarrierUtil.class);
  33
  34
  35     private BarrierUtil() {
  36         throw new IllegalStateException("This class should not be instantiated.");
  37     }
  38
  39
  40     /**
  41      * chain a barrier message - regardless of previous result and use given {@link Function} to combine
  42      * original result and barrier result
  43      *
  44      * @param <T>                type of input future
  45      * @param input              future to chain barrier to
  46      * @param nodeRef            target device
  47      * @param transactionService barrier service
  48      * @param compositeTransform
  49      * @return future holding both results (input and of the barrier)
  50      */
  51     public static <T> ListenableFuture<RpcResult<T>> chainBarrier(
  52             final ListenableFuture<RpcResult<T>> input, final NodeRef nodeRef,
  53             final FlowCapableTransactionService transactionService,
  54             final Function<Pair<RpcResult<T>, RpcResult<Void>>, RpcResult<T>> compositeTransform) {
  55         final MutablePair<RpcResult<T>, RpcResult<Void>> resultPair = new MutablePair<>();
  56
  57         // store input result and append barrier
  58         final ListenableFuture<RpcResult<Void>> barrierResult = Futures.transform(input,
  59                 new AsyncFunction<RpcResult<T>, RpcResult<Void>>() {
  60                     @Override
  61                     public ListenableFuture<RpcResult<Void>> apply(@Nullable final RpcResult<T> interInput) throws Exception {
  62                         resultPair.setLeft(interInput);
  63                         final SendBarrierInput barrierInput = createSendBarrierInput(nodeRef);
  64                         return JdkFutureAdapters.listenInPoolThread(transactionService.sendBarrier(barrierInput));
  65                     }
  66                 });
  67         // store barrier result and return initiated pair
  68         final ListenableFuture<Pair<RpcResult<T>, RpcResult<Void>>> compositeResult = Futures.transform(
  69                 barrierResult, new Function<RpcResult<Void>, Pair<RpcResult<T>, RpcResult<Void>>>() {
  70                     @Nullable
  71                     @Override
  72                     public Pair<RpcResult<T>, RpcResult<Void>> apply(@Nullable final RpcResult<Void> input) {
  73                         resultPair.setRight(input);
  74                         return resultPair;
  75                     }
  76                 });
  77         // append assembling transform to barrier result
  78         return Futures.transform(compositeResult, compositeTransform);
  79     }
  80
  81     /**
  82      * @param nodeRef rpc routing context
  83      * @return input for {@link FlowCapableTransactionService#sendBarrier(SendBarrierInput)}
  84      */
  85     public static SendBarrierInput createSendBarrierInput(final NodeRef nodeRef) {
  86         return new SendBarrierInputBuilder()
  87                 .setNode(nodeRef)
  88                 .build();
  89     }
  90 }