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.Futures;
  13 import com.google.common.util.concurrent.ListenableFuture;
  14 import com.google.common.util.concurrent.MoreExecutors;
  15 import org.apache.commons.lang3.tuple.MutablePair;
  16 import org.apache.commons.lang3.tuple.Pair;
  17 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.transaction.rev150304.FlowCapableTransactionService;
  18 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.transaction.rev150304.SendBarrierInput;
  19 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.transaction.rev150304.SendBarrierInputBuilder;
  20 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.transaction.rev150304.SendBarrierOutput;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.NodeRef;
  22 import org.opendaylight.yangtools.yang.common.RpcResult;
  23
  24 /**
  25  * Provides barrier message chaining and factory methods.
  26  */
  27 public final class BarrierUtil {
  28
  29
  30     private BarrierUtil() {
  31         throw new IllegalStateException("This class should not be instantiated.");
  32     }
  33
  34
  35     /**
  36      * Chain a barrier message - regardless of previous result and use given {@link Function} to combine
  37      * original result and barrier result.
  38      *
  39      * @param <T>                type of input future
  40      * @param input              future to chain barrier to
  41      * @param nodeRef            target device
  42      * @param transactionService barrier service
  43      * @param compositeTransform composite transform
  44      * @return future holding both results (input and of the barrier)
  45      */
  46     public static <T> ListenableFuture<RpcResult<T>> chainBarrier(
  47             final ListenableFuture<RpcResult<T>> input, final NodeRef nodeRef,
  48             final FlowCapableTransactionService transactionService,
  49             final Function<Pair<RpcResult<T>, RpcResult<SendBarrierOutput>>, RpcResult<T>> compositeTransform) {
  50         final MutablePair<RpcResult<T>, RpcResult<SendBarrierOutput>> resultPair = new MutablePair<>();
  51
  52         // store input result and append barrier
  53         final ListenableFuture<RpcResult<SendBarrierOutput>> barrierResult = Futures.transformAsync(input,
  54             interInput -> {
  55                 resultPair.setLeft(interInput);
  56                 final SendBarrierInput barrierInput = createSendBarrierInput(nodeRef);
  57                 return transactionService.sendBarrier(barrierInput);
  58             }, MoreExecutors.directExecutor());
  59         // store barrier result and return initiated pair
  60         final ListenableFuture<Pair<RpcResult<T>, RpcResult<SendBarrierOutput>>> compositeResult = Futures.transform(
  61                 barrierResult,
  62             input1 -> {
  63                 resultPair.setRight(input1);
  64                 return resultPair;
  65             }, MoreExecutors.directExecutor());
  66         // append assembling transform to barrier result
  67         return Futures.transform(compositeResult, compositeTransform, MoreExecutors.directExecutor());
  68     }
  69
  70     /**
  71      * Creates barrier input.
  72      *
  73      * @param nodeRef rpc routing context
  74      * @return input for {@link FlowCapableTransactionService#sendBarrier(SendBarrierInput)}
  75      */
  76     public static SendBarrierInput createSendBarrierInput(final NodeRef nodeRef) {
  77         return new SendBarrierInputBuilder()
  78                 .setNode(nodeRef)
  79                 .build();
  80     }
  81 }