pushmessage.java

P2P协议GUNTELLA的java源代码

/*
 * Copyright (C) 2000-2001  Ken McCrary
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Email: [e-mail]
 */
package com.kenmccrary.jtella;

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;


/**
 *  Push message, represents a request to push a file to a receiving node
 *
 *
 */
public class PushMessage extends Message
{
  private SearchReplyMessage searchReplyMessage;
  private int fileIndex;
  private String ipAddress;
  private short port;
  
  /**
   *  Construct a PUSH message, indicates a node wants this servant
   *  to connect and transfer a file
   *
   */
  PushMessage()
  {
    super(Message.PUSH);
  }

  /**
   *  Construct a PushMessage from network data
   *
   *  @param rawMessage binary data from a connection
   *  @param originatingConnection Connection creating this message
   */
  PushMessage(short[] rawMessage, Connection originatingConnection)
  {
    super(rawMessage, originatingConnection);
  }
  
  
  /**
   *  Construct a PushMessage using a previously received SearchReplyMessage.
   *
   *  @param searchReplyMessage search reply containing file to push
   *  @param fileIndex index of file (from FileRecord) to push
   *  @param ipAddress for push transfer
   *  @param port port for push transfer
   */
  public PushMessage(SearchReplyMessage searchReplyMessage,
                     int fileIndex,
                     String ipAddress,
                     short port)
  {
    super(Message.PUSH);
    this.searchReplyMessage = searchReplyMessage;
    this.fileIndex = fileIndex;
    this.ipAddress = ipAddress;
    this.port = port;
    
    buildPayload();
  }              

  /**
   *  Retrieve the client GUID targeted by this push request
   *
   *  @return client GUID
   */
  public GUID getClientIdentifier()
  {
    short[] guidData = new short[16];

    for (int i = 0; i < 16; i++) 
    {
      guidData[i] = payload[i];
    }

    return new GUID(guidData);
  }

  /**
   *  Retrieve the index of the file to push
   *
   *  @return file index
   */
  public int getFileIndex()
  {
    int byte1 = payload[16];
    int byte2 = payload[17];
    int byte3 = payload[18];
    int byte4 = payload[19];

    return byte1 | (byte2 << 8) | (byte3 << 16) | (byte4 << 24);
  }

  /**
   *  Get the IP Address to push to 
   *
   *  @return IP address
   */
  public String getIPAddress()
  {
    int byte1 = payload[20];
    int byte2 = payload[21];
    int byte3 = payload[22];
    int byte4 = payload[23];

    return (new Integer(byte1)).toString() + "." +
           (new Integer(byte2)).toString() + "." +
           (new Integer(byte3)).toString() + "." +
           (new Integer(byte4)).toString();
  }
  
  /**
   *  Get the port the connection should use
   *
   *  @return port
   */
  public short getPort()
  {
    int byte1 = payload[24];
    int byte2 = payload[25];

    return (short)(byte1 | (byte2 <<8));
  }
  
  /**
   *   Builds the PUSH message payload
   *
   */
  void buildPayload()
  {
    try
    {
      ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
      DataOutputStream dataStream = new DataOutputStream(byteStream);
     
      // Servant Identifier
      short[] guidData = searchReplyMessage.getClientIdentifier().getData();
      for (int i = 0; i < guidData.length; i++) 
      {
        dataStream.writeByte((byte)guidData[i]);
      }
      
      // File Index
      int indexByte1 = 0x000000FF & fileIndex;
      int indexByte2 = (0x0000FF00 & fileIndex) >> 8;
      int indexByte3 = (0x00FF0000 & fileIndex) >> 16;
      int indexByte4 = (0xFF000000 & fileIndex) >> 24;
      dataStream.writeByte(indexByte1);
      dataStream.writeByte(indexByte2);
      dataStream.writeByte(indexByte3);
      dataStream.writeByte(indexByte4);

      
      // IP Address
      int beginIndex = 0;
      int endIndex = ipAddress.indexOf('.');

      int ip1 = Integer.parseInt(ipAddress.substring(beginIndex, endIndex));

      beginIndex = endIndex + 1;
      endIndex = ipAddress.indexOf('.', beginIndex);

      int ip2 = Integer.parseInt(ipAddress.substring(beginIndex, endIndex));

      beginIndex = endIndex + 1;
      endIndex = ipAddress.indexOf('.', beginIndex);

      int ip3 = Integer.parseInt(ipAddress.substring(beginIndex, endIndex));

      beginIndex = endIndex + 1;

      int ip4 = Integer.parseInt(ipAddress.substring(beginIndex, ipAddress.length()));

      dataStream.write(ip1);
      dataStream.write(ip2);
      dataStream.write(ip3);
      dataStream.write(ip4);
      
      // Port (little endian)
      int byte1 = 0x00FF & port;
      int byte2 = (0xFF00 & port) >> 8;
      dataStream.write(byte1);
      dataStream.write(byte2);

      addPayload(byteStream.toByteArray());
      dataStream.close();
      
    }    
    catch (IOException io)
    {
    }   
  }    

}