/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.cassandra.db;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import org.apache.cassandra.io.ICompactSerializer;
import org.apache.cassandra.utils.ByteBufferUtil;
/*
* The read response message is sent by the server when reading data
* this encapsulates the tablename and the row that has been read.
* The table name is needed so that we can use it to create repairs.
*/
public class ReadResponse
{
private static ICompactSerializer<ReadResponse> serializer_;
static
{
serializer_ = new ReadResponseSerializer();
}
public static ICompactSerializer<ReadResponse> serializer()
{
return serializer_;
}
private final Row row_;
private final ByteBuffer digest_;
public ReadResponse(ByteBuffer digest )
{
assert digest != null;
digest_= digest;
row_ = null;
}
public ReadResponse(Row row)
{
assert row != null;
row_ = row;
digest_ = null;
}
public Row row()
{
return row_;
}
public ByteBuffer digest()
{
return digest_;
}
public boolean isDigestQuery()
{
return digest_ != null;
}
}
class ReadResponseSerializer implements ICompactSerializer<ReadResponse>
{
public void serialize(ReadResponse rm, DataOutputStream dos) throws IOException
{
dos.writeInt(rm.isDigestQuery() ? rm.digest().remaining() : 0);
ByteBuffer buffer = rm.isDigestQuery() ? rm.digest() : ByteBufferUtil.EMPTY_BYTE_BUFFER;
ByteBufferUtil.write(buffer, dos);
dos.writeBoolean(rm.isDigestQuery());
if (!rm.isDigestQuery())
{
Row.serializer().serialize(rm.row(), dos);
}
}
public ReadResponse deserialize(DataInputStream dis) throws IOException
{
byte[] digest = null;
int digestSize = dis.readInt();
if (digestSize > 0)
{
digest = new byte[digestSize];
dis.readFully(digest, 0, digestSize);
}
boolean isDigest = dis.readBoolean();
assert isDigest == digestSize > 0;
Row row = null;
if (!isDigest)
{
row = Row.serializer().deserialize(dis);
}
return isDigest ? new ReadResponse(ByteBuffer.wrap(digest)) : new ReadResponse(row);
}
}