vpp-api/java/jvpp/org/openvpp/jvpp/future/FutureJVppInvokerFacade.java

   1 /*
   2  * Copyright (c) 2016 Cisco and/or its affiliates.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package org.openvpp.jvpp.future;
  18
  19
  20 import org.openvpp.jvpp.JVpp;
  21 import org.openvpp.jvpp.VppInvocationException;
  22 import org.openvpp.jvpp.dto.*;
  23
  24 import java.util.Map;
  25 import java.util.Objects;
  26 import java.util.concurrent.CompletableFuture;
  27 import java.util.concurrent.CompletionStage;
  28 import org.openvpp.jvpp.notification.NotificationRegistryProviderContext;
  29
  30 /**
  31 * Future facade on top of JVpp
  32 */
  33 public class FutureJVppInvokerFacade extends NotificationRegistryProviderContext implements FutureJVppInvoker {
  34
  35     private final JVpp jvpp;
  36
  37     /**
  38      * Guarded by self
  39      */
  40     private final Map<Integer, CompletableFuture<? extends JVppReply<?>>> requests;
  41
  42     public FutureJVppInvokerFacade(final JVpp jvpp,
  43                                    final Map<Integer, CompletableFuture<? extends JVppReply<?>>> requestMap) {
  44         this.jvpp =  Objects.requireNonNull(jvpp, "Null jvpp");
  45         // Request map represents the shared state between this facade and it's callback
  46         // where facade puts futures in and callback completes + removes them
  47         // TODO what if the call never completes ?
  48         this.requests = Objects.requireNonNull(requestMap, "Null requestMap");
  49     }
  50
  51     protected final Map<Integer, CompletableFuture<? extends JVppReply<?>>> getRequests() {
  52         return this.requests;
  53     }
  54
  55     // TODO use Optional in Future, java8
  56
  57     @Override
  58     @SuppressWarnings("unchecked")
  59     public <REQ extends JVppRequest, REPLY extends JVppReply<REQ>> CompletionStage<REPLY> send(REQ req) {
  60         synchronized(requests) {
  61             try {
  62                 final CompletableFuture<REPLY> replyCompletableFuture;
  63                 final int contextId = jvpp.send(req);
  64
  65                 if(req instanceof JVppDump) {
  66                     replyCompletableFuture = (CompletableFuture<REPLY>) new CompletableDumpFuture<>(contextId);
  67                 } else {
  68                     replyCompletableFuture = new CompletableFuture<>();
  69                 }
  70
  71                 requests.put(contextId, replyCompletableFuture);
  72                 if(req instanceof JVppDump) {
  73                     requests.put(jvpp.send(new ControlPing()), replyCompletableFuture);
  74                 }
  75                 return replyCompletableFuture;
  76             } catch (VppInvocationException ex) {
  77                 final CompletableFuture<REPLY> replyCompletableFuture = new CompletableFuture<>();
  78                 replyCompletableFuture.completeExceptionally(ex);
  79                 return replyCompletableFuture;
  80             }
  81         }
  82     }
  83
  84     static final class CompletableDumpFuture<T extends JVppReplyDump<?, ?>> extends CompletableFuture<T> {
  85         // The reason why this is not final is the instantiation of ReplyDump DTOs
  86         // Their instantiation must be generated, so currently the DTOs are created in callback and set when first dump reponses
  87         // is handled in the callback.
  88         private T replyDump;
  89         private final long contextId;
  90
  91         CompletableDumpFuture(final long contextId) {
  92             this.contextId = contextId;
  93         }
  94
  95         long getContextId() {
  96             return contextId;
  97         }
  98
  99         T getReplyDump() {
 100             return replyDump;
 101         }
 102
 103         void setReplyDump(final T replyDump) {
 104             this.replyDump = replyDump;
 105         }
 106     }
 107
 108     @Override
 109     public void close() throws Exception {
 110         // NOOP
 111     }
 112 }