content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.chemistry.opencmis.server.async.impl;
  
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.LinkedBlockingQueue;
  import java.util.concurrent.ThreadFactory;
  import java.util.concurrent.ThreadPoolExecutor;
  import java.util.concurrent.TimeUnit;
  
  import javax.servlet.AsyncContext;
  
  import org.apache.chemistry.opencmis.server.async.AsyncCmisExecutor;
  
  /**
   * A simple {@link AsyncCmisExecutor} implementation that uses a
   * {@code ThreadPoolExecutor} for executing asynchronous CMIS requests.
   */
  public class SimpleAsyncCmisExecutor implements AsyncCmisExecutor {
  
      private static int cmisThreadInitNumber = 0;
  
      private ExecutorService executorService;
      private long timeout;
  
      public SimpleAsyncCmisExecutor() {
          executorService = createExecutorService();
          timeout = 24 * 60 * 60 * 1000; // 24 hours
      }
  
      private static synchronized int nextThreadNum() {
          return cmisThreadInitNumber++;
      }
  
      /**
       * Creates an ExecutorService instance.
       */
      private ExecutorService createExecutorService() {
          final ThreadGroup threadGroup = new ThreadGroup("cmis-thread-group");
          final ThreadFactory threadFactory = new ThreadFactory() {
              @Override
              public Thread newThread(Runnable r) {
                  return new Thread(threadGroup, r, "cmis-" + nextThreadNum());
              }
          };
  
          int processors = Runtime.getRuntime().availableProcessors();
          int maximumPoolSize = processors * 100;
          int corePoolSize = processors;
          int queueSize = maximumPoolSize / 2;
  
          ThreadPoolExecutor threadPoolexecutor = new ThreadPoolExecutor(corePoolSize, maximumPoolSize, 60L,
                  TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>(queueSize), threadFactory);
  
          return threadPoolexecutor;
      }
  
      /**
       * Waits until all running threads are stopped.
       */
      public void destroy() {
          executorService.shutdown();
      }
  
      /**
       * Gets the timeout for the AsyncContext.
       * 
       * @return the timeout in milliseconds
       */
      public long getTimeout() {
          return timeout;
      }
  
      /**
       * Sets the timeout for the AsyncContext.
       * 
       * @param timeout
       *            the timeout in milliseconds
       * 
       * @see AsyncContext#setTimeout(long)
       */
      public void setTimeout(long timeout) {
          this.timeout = timeout;
      }
  
      @Override
      public void execute(AsyncContext asyncContext, Runnable runable) {
          asyncContext.setTimeout(timeout);
          asyncContext.addListener(new SimpleCmisAsyncListener());
  
          executorService.submit(runable);
      }
  }
  