//
   //  ========================================================================
   //  Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.server;
  
  import java.io.IOException;
  import java.util.concurrent.BlockingQueue;
  import java.util.concurrent.TimeUnit;
  
  import org.eclipse.jetty.util.BlockingArrayQueue;
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  
  
  /* ------------------------------------------------------------ */
  /**
   * An asynchronously writing NCSA Request Log
   */
  public class AsyncNCSARequestLog extends NCSARequestLog
  {
      private static final Logger LOG = Log.getLogger(AsyncNCSARequestLog.class);
      private final BlockingQueue<String> _queue;
      private transient WriterThread _thread;
      private boolean _warnedFull;
  
      public AsyncNCSARequestLog()
      {
          this(null,null);
      }
  
      public AsyncNCSARequestLog(BlockingQueue<String> queue)
      {
          this(null,queue);
      }
  
      public AsyncNCSARequestLog(String filename)
      {
          this(filename,null);
      }
  
      public AsyncNCSARequestLog(String filename,BlockingQueue<String> queue)
      {
          super(filename);
          if (queue==null)
              queue=new BlockingArrayQueue<>(1024);
          _queue=queue;
      }
  
      private class WriterThread extends Thread
      {
          WriterThread()
          {
              setName("AsyncNCSARequestLog@"+Integer.toString(AsyncNCSARequestLog.this.hashCode(),16));
          }
  
          @Override
          public void run()
          {
              while (isRunning())
              {
                  try
                  {
                      String log = _queue.poll(10,TimeUnit.SECONDS);
                      if (log!=null)
                          AsyncNCSARequestLog.super.write(log);
  
                      while(!_queue.isEmpty())
                      {
                          log=_queue.poll();
                          if (log!=null)
                              AsyncNCSARequestLog.super.write(log);
                      }
                  }
                  catch (IOException e)
                  {
                      LOG.warn(e);
                  }
                  catch (InterruptedException e)
                  {
                      LOG.ignore(e);
                  }
              }
          }
      }
 
     @Override
     protected synchronized void doStart() throws Exception
     {
         super.doStart();
         _thread = new WriterThread();
         _thread.start();
     }
 
     @Override
     protected void doStop() throws Exception
     {
         _thread.interrupt();
         _thread.join();
         super.doStop();
         _thread=null;
     }
 
     @Override
     public void write(String log) throws IOException
     {
         if (!_queue.offer(log))
         {
             if (_warnedFull)
                 LOG.warn("Log Queue overflow");
             _warnedFull=true;
         }
     }
 
 }