/*
* 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]
*
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*
*
* Copyright 2006-2009 Sun Microsystems, Inc.
* Portions Copyright 2013 ForgeRock AS.
*/
package org.opends.server.replication.protocol;
import java.util.zip.DataFormatException;
import java.io.UnsupportedEncodingException;
import org.opends.server.replication.common.AssuredMode;
import org.opends.server.replication.common.ChangeNumber;
/**
* Abstract class that must be extended to define a message
* used for sending Updates between servers.
*/
public class UpdateMsg extends ReplicationMsg
implements Comparable<UpdateMsg>
{
/**
* Protocol version.
*/
protected short protocolVersion;
/**
* The ChangeNumber of this update.
*/
protected ChangeNumber changeNumber;
/**
* True when the update must use assured replication.
*/
protected boolean assuredFlag = false;
/**
* When assuredFlag is true, defines the requested assured mode.
*/
protected AssuredMode assuredMode = AssuredMode.SAFE_DATA_MODE;
/**
* When assured mode is safe data, gives the requested level.
*/
protected byte safeDataLevel = (byte)1;
/**
* The payload that must be encoded in this message.
*/
private byte[] payload;
/**
* Creates a new empty UpdateMsg.
*/
protected UpdateMsg()
{}
/**
* Creates a new UpdateMsg with the given information.
*
* @param bytes A Byte Array with the encoded form of the message.
*
* @throws DataFormatException If bytes is not valid.
*/
UpdateMsg(byte[] bytes) throws DataFormatException
{
// Decode header
int pos = decodeHeader(MSG_TYPE_GENERIC_UPDATE, bytes);
/* Read the payload : all the remaining bytes but the terminating 0 */
int length = bytes.length - pos;
payload = new byte[length];
try
{
System.arraycopy(bytes, pos, payload, 0, length);
} catch (IndexOutOfBoundsException e)
{
throw new DataFormatException(e.getMessage());
} catch (ArrayStoreException e)
{
throw new DataFormatException(e.getMessage());
} catch (NullPointerException e)
{
throw new DataFormatException(e.getMessage());
}
}
/**
* Creates a new UpdateMsg with the given informations.
* <p>
* This constructor is only used for testing.
*
* @param changeNumber The ChangeNumber associated with the change
* encoded in this message.
* @param payload The payload that must be encoded in this message.
*/
public UpdateMsg(ChangeNumber changeNumber, byte[] payload)
{
this.payload = payload;
this.protocolVersion = ProtocolVersion.getCurrentVersion();
this.changeNumber = changeNumber;
}
/**
* Get the ChangeNumber from the message.
* @return the ChangeNumber
*/
public ChangeNumber getChangeNumber()
{
return changeNumber;
}
/**
* Get a boolean indicating if the Update must be processed as an
* Asynchronous or as an assured replication.
*
* @return Returns the assuredFlag.
*/
public boolean isAssured()
{
return assuredFlag;
}
/**
* Set the Update message as an assured message.
*
* @param assured If the message is assured or not. Using true implies
* setAssuredMode method must be called.
*/
public void setAssured(boolean assured)
{
assuredFlag = assured;
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object obj)
{
return obj != null && obj.getClass() == this.getClass() &&
changeNumber.equals(((UpdateMsg) obj).changeNumber);
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode()
{
return changeNumber.hashCode();
}
/**
* {@inheritDoc}
*/
public int compareTo(UpdateMsg msg)
{
return changeNumber.compareTo(msg.getChangeNumber());
}
/**
* Get the assured mode in this message.
* @return The assured mode in this message
*/
public AssuredMode getAssuredMode()
{
return assuredMode;
}
/**
* Get the safe data level in this message.
* @return The safe data level in this message
*/
public byte getSafeDataLevel()
{
return safeDataLevel;
}
/**
* Set the assured mode. Assured boolean must be set to true for this field
* to mean something.
* @param assuredMode The chosen assured mode.
*/
public void setAssuredMode(AssuredMode assuredMode)
{
this.assuredMode = assuredMode;
}
/**
* Set the safe data level. Assured mode should be set to safe data for this
* field to mean something.
* @param safeDataLevel The chosen safe data level.
*/
public void setSafeDataLevel(byte safeDataLevel)
{
this.safeDataLevel = safeDataLevel;
}
/**
* Get the version included in the update message. Means the replication
* protocol version with which this update message was instantiated.
*
* @return The version with which this update message was instantiated.
*/
public short getVersion()
{
return protocolVersion;
}
/**
* Return the number of bytes used by this message.
*
* @return The number of bytes used by this message.
*/
public int size()
{
return 10 + payload.length;
}
/**
* Encode the common header for all the UpdateMsg. This uses the current
* protocol version.
*
* @param type the type of UpdateMsg to encode.
* @param additionalLength additional length needed to encode the remaining
* part of the UpdateMsg.
* @param version The ProtocolVersion to use when encoding.
* @return a byte array containing the common header and enough space to
* encode the remaining bytes of the UpdateMsg as was specified
* by the additionalLength.
* (byte array length = common header length + additionalLength)
* @throws UnsupportedEncodingException if UTF-8 is not supported.
*/
protected byte[] encodeHeader(byte type, int additionalLength, short version)
throws UnsupportedEncodingException
{
byte[] changeNumberByte =
this.getChangeNumber().toString().getBytes("UTF-8");
/* The message header is stored in the form :
* <operation type><protocol version><changenumber><assured>
* <assured mode> <safe data level>
* the length of result byte array is therefore :
* 1 + 1 + change number length + 1 + 1
* + 1 + 1 + additional_length
*/
int length = 6 + changeNumberByte.length + additionalLength;
byte[] encodedMsg = new byte[length];
/* put the type of the operation */
encodedMsg[0] = type;
/* put the protocol version */
encodedMsg[1] = (byte)ProtocolVersion.getCurrentVersion();
int pos = 2;
/* Put the ChangeNumber */
pos = addByteArray(changeNumberByte, encodedMsg, pos);
/* Put the assured flag */
encodedMsg[pos++] = (assuredFlag ? (byte) 1 : 0);
/* Put the assured mode */
encodedMsg[pos++] = assuredMode.getValue();
/* Put the safe data level */
encodedMsg[pos++] = safeDataLevel;
return encodedMsg;
}
/**
* Decode the Header part of this Update Message, and check its type.
*
* @param type The allowed type of this Update Message.
* @param encodedMsg the encoded form of the UpdateMsg.
* @return the position at which the remaining part of the message starts.
* @throws DataFormatException if the encodedMsg does not contain a valid
* common header.
*/
protected int decodeHeader(byte type, byte[] encodedMsg)
throws DataFormatException
{
/* The message header is stored in the form :
* <operation type><protocol version><changenumber><assured>
* <assured mode> <safe data level>
*/
if (!(type == encodedMsg[0]))
throw new DataFormatException("byte[] is not a valid update msg: "
+ encodedMsg[0]);
/* read the protocol version */
protocolVersion = (short)encodedMsg[1];
try
{
/* Read the changeNumber */
int pos = 2;
int length = getNextLength(encodedMsg, pos);
String changenumberStr = new String(encodedMsg, pos, length, "UTF-8");
pos += length + 1;
changeNumber = new ChangeNumber(changenumberStr);
/* Read the assured information */
assuredFlag = encodedMsg[pos++] == 1;
/* Read the assured mode */
assuredMode = AssuredMode.valueOf(encodedMsg[pos++]);
/* Read the safe data level */
safeDataLevel = encodedMsg[pos++];
return pos;
} catch (UnsupportedEncodingException e)
{
throw new DataFormatException("UTF-8 is not supported by this jvm.");
} catch (IllegalArgumentException e)
{
throw new DataFormatException(e.getMessage());
}
}
/**
* Returns the encoded representation of this update message using the current
* protocol version.
*
* @return The encoded representation of this update message.
* @throws UnsupportedEncodingException
* If the message could not be encoded.
*/
public byte[] getBytes() throws UnsupportedEncodingException
{
return getBytes(ProtocolVersion.getCurrentVersion());
}
/**
* This implementation is only called during unit testing, so we are free to
* force the protocol version. Underlying implementations override this method
* in order to provide version specific encodings.
*
* {@inheritDoc}
*/
@Override
public byte[] getBytes(short protocolVersion)
throws UnsupportedEncodingException
{
/* Encode the header in a byte[] large enough to also contain the payload */
byte[] resultByteArray = encodeHeader(MSG_TYPE_GENERIC_UPDATE,
payload.length, ProtocolVersion.getCurrentVersion());
int pos = resultByteArray.length - payload.length;
/* Add the payload */
for (int i = 0; i < payload.length; i++, pos++)
{
resultByteArray[pos] = payload[i];
}
return resultByteArray;
}
/**
* Get the payload of the UpdateMsg.
*
* @return The payload of the UpdateMsg.
*/
public byte[] getPayload()
{
return payload;
}
}