WindowMessage.java revision a395dd575518d9e5280fc5d5d5ef47c61b174647
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE
* or https://OpenDS.dev.java.net/OpenDS.LICENSE.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE. If applicable,
* add the following below this CDDL HEADER, with the fields enclosed
* by brackets "[]" replaced with your own identifying information:
* Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
*
* Copyright 2006-2008 Sun Microsystems, Inc.
*/
package org.opends.server.replication.protocol;
import java.io.Serializable;
import java.io.UnsupportedEncodingException;
import java.util.zip.DataFormatException;
/**
* This message is used by LDAP server or by Replication Servers to
* update the send window of the remote entities.
*
* A receiving entity should create such a message with a given credit
* when it wants to open the send window of the remote entity.
* A LDAP or Replication Server should increase its send window when receiving
* such a message.
*/
public class WindowMessage extends ReplicationMessage implements
Serializable
{
private static final long serialVersionUID = 8442267608764026867L;
private final int numAck;
/**
* Create a new WindowMessage.
*
* @param numAck The number of acknowledged messages.
* The window will be increase by this credit number.
*/
public WindowMessage(int numAck)
{
this.numAck = numAck;
}
/**
* Creates a new WindowMessage from its encoded form.
*
* @param in The byte array containing the encoded form of the
* WindowMessage.
* @throws DataFormatException If the byte array does not contain a valid
* encoded form of the WindowMessage.
*/
public WindowMessage(byte[] in) throws DataFormatException
{
/* The WindowMessage is encoded in the form :
* <numAck>
*/
try
{
/* first byte is the type */
if (in[0] != MSG_TYPE_WINDOW)
throw new DataFormatException("input is not a valid Window Message");
int pos = 1;
/*
* read the number of acks contained in this message.
* first calculate the length then construct the string
*/
int length = getNextLength(in, pos);
String numAckStr = new String(in, pos, length, "UTF-8");
pos += length +1;
numAck = Integer.parseInt(numAckStr);
} catch (UnsupportedEncodingException e)
{
throw new DataFormatException("UTF-8 is not supported by this jvm.");
}
}
/**
* {@inheritDoc}
*/
@Override
public byte[] getBytes()
{
/*
* WindowMessage contains.
* <numAck>
*/
try {
byte[] byteNumAck = String.valueOf(numAck).getBytes("UTF-8");
int length = 1 + byteNumAck.length + 1;
byte[] resultByteArray = new byte[length];
/* put the type of the operation */
resultByteArray[0] = MSG_TYPE_WINDOW;
int pos = 1;
pos = addByteArray(byteNumAck, resultByteArray, pos);
return resultByteArray;
}
catch (UnsupportedEncodingException e)
{
return null;
}
}
/**
* Get the number of message acknowledged by the Window Message.
*
* @return the number of message acknowledged by the Window Message.
*/
public int getNumAck()
{
return numAck;
}
}