internalmessageio.java

ALGAE是一个快速创建算法演示的框架。目前支持的算法实现语言包括java和c

/**
 * InternalMessageIO.java
 *
 *
 * Created: Fri Jun 30 
 *
 * @author Steven Zeil
 * @version
 */

package edu.odu.cs.zeil.AlgAE.Server;

import edu.odu.cs.zeil.AlgAE.Debug;
import edu.odu.cs.zeil.AlgAE.Queue;

import edu.odu.cs.zeil.AlgAE.Message;
import edu.odu.cs.zeil.AlgAE.MessageIO;
import edu.odu.cs.zeil.AlgAE.ParameterizedMessage;


public class InternalMessageIO
{

  class QueuedMessageIO implements MessageIO
  {
    private Queue inq;
    private Queue outq;
    
    QueuedMessageIO (Queue in, Queue out)
    {
      inq = in;
      outq = out;
    }


    /**
     *   Send a message
     */
    public void send (ParameterizedMessage pmsg)
    {
      boolean wasEmpty;
      synchronized (outq)
      {
	wasEmpty = outq.isEmpty();
	outq.addToRear (pmsg);
	if (wasEmpty)
	  outq.notifyAll();
      }
    }
  
	      
    /**
     *  Read a message
     **/
    public ParameterizedMessage read()
    {
      boolean noMsgWaiting = true;
      ParameterizedMessage pmsg = null;
      while (noMsgWaiting)
	{
	  synchronized (inq)
	    {
	      noMsgWaiting = inq.isEmpty();
	      if (noMsgWaiting)
		{
		  try {
		    inq.wait();
		  }
		  catch (java.lang.InterruptedException e) {
		  }
		}
	      else
		{
		  pmsg = (ParameterizedMessage)inq.getFront();
		  inq.removeFront();
		}
	    }
	}
      return pmsg;
    }

    public void close()
    {
    }

  }
  

  private Queue q1;
  private Queue q2;

  private QueuedMessageIO serverio;
  private QueuedMessageIO clientio;

  public InternalMessageIO()
  {
    q1 = new Queue();
    q2 = new Queue();
    
    serverio = new QueuedMessageIO(q1,q2);
    clientio = new QueuedMessageIO(q2,q1);
  }
  
  
    
  public MessageIO serverIO()
  {
    return serverio;
  }

  public MessageIO clientIO()
  {
    return clientio;
  }
  
 } // InternalMessageIO