org.apache.cassandra.serializers.CollectionSerializer Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of cassandra-all Show documentation
Show all versions of cassandra-all Show documentation
A fork of the Apache Cassandra Project ready to embed Elasticsearch.
/*
* 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.serializers;
import java.nio.ByteBuffer;
import java.util.Collection;
import java.util.List;
import org.apache.cassandra.transport.Server;
import org.apache.cassandra.utils.ByteBufferUtil;
public abstract class CollectionSerializer implements TypeSerializer
{
protected abstract List serializeValues(T value);
protected abstract int getElementCount(T value);
public abstract T deserializeForNativeProtocol(ByteBuffer buffer, int version);
public abstract void validateForNativeProtocol(ByteBuffer buffer, int version);
public ByteBuffer serialize(T value)
{
List values = serializeValues(value);
// See deserialize() for why using the protocol v3 variant is the right thing to do.
return pack(values, getElementCount(value), Server.VERSION_3);
}
public T deserialize(ByteBuffer bytes)
{
// The only cases we serialize/deserialize collections internally (i.e. not for the protocol sake),
// is:
// 1) when collections are frozen
// 2) for internal calls.
// In both case, using the protocol 3 version variant is the right thing to do.
return deserializeForNativeProtocol(bytes, Server.VERSION_3);
}
public void validate(ByteBuffer bytes) throws MarshalException
{
// Same thing as above
validateForNativeProtocol(bytes, Server.VERSION_3);
}
public static ByteBuffer pack(Collection buffers, int elements, int version)
{
int size = 0;
for (ByteBuffer bb : buffers)
size += sizeOfValue(bb, version);
ByteBuffer result = ByteBuffer.allocate(sizeOfCollectionSize(elements, version) + size);
writeCollectionSize(result, elements, version);
for (ByteBuffer bb : buffers)
writeValue(result, bb, version);
return (ByteBuffer)result.flip();
}
protected static void writeCollectionSize(ByteBuffer output, int elements, int version)
{
output.putInt(elements);
}
public static int readCollectionSize(ByteBuffer input, int version)
{
return input.getInt();
}
protected static int sizeOfCollectionSize(int elements, int version)
{
return 4;
}
public static void writeValue(ByteBuffer output, ByteBuffer value, int version)
{
if (value == null)
{
output.putInt(-1);
return;
}
output.putInt(value.remaining());
output.put(value.duplicate());
}
public static ByteBuffer readValue(ByteBuffer input, int version)
{
int size = input.getInt();
if (size < 0)
return null;
return ByteBufferUtil.readBytes(input, size);
}
public static int sizeOfValue(ByteBuffer value, int version)
{
return value == null ? 4 : 4 + value.remaining();
}
}