runtime/org.argeo.slc.detached/src/main/java/org/argeo/slc/detached/drivers/MemoryDriver.java

   1 /*
   2  * Copyright (C) 2007-2012 Mathieu Baudier
   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 package org.argeo.slc.detached.drivers;
  17
  18 import org.argeo.slc.detached.DetachedAnswer;
  19 import org.argeo.slc.detached.DetachedClient;
  20 import org.argeo.slc.detached.DetachedDriver;
  21 import org.argeo.slc.detached.DetachedRequest;
  22
  23 /**
  24  * Implements both <code>DetachedClient</code> and <code>DetachedDriver</code>
  25  * using memory access
  26  */
  27 public class MemoryDriver implements DetachedClient, DetachedDriver {
  28         private DetachedRequest currentRequest = null;
  29         private DetachedAnswer currentAnswer = null;
  30
  31         // DRIVER
  32         public synchronized DetachedRequest receiveRequest() throws Exception {
  33                 while (currentRequest == null)
  34                         this.wait(500);
  35                 return currentRequest;
  36         }
  37
  38         public synchronized void sendAnswer(DetachedAnswer answer) throws Exception {
  39                 currentAnswer = answer;
  40                 this.notify();
  41         }
  42
  43         // CLIENT
  44         public synchronized DetachedAnswer receiveAnswer() throws Exception {
  45                 while (currentAnswer == null)
  46                         this.wait(500);
  47                 DetachedAnswer answer = currentAnswer;
  48                 currentAnswer = null;
  49                 currentRequest = null;
  50                 return answer;
  51         }
  52
  53         public synchronized void sendRequest(DetachedRequest request)
  54                         throws Exception {
  55                 currentRequest = request;
  56                 this.notify();
  57         }
  58
  59         public void stop() {
  60                 // NOTHING
  61         }
  62 }