src/java/org/apache/cassandra/db/marshal/CounterColumnType.java

/*
 * 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.marshal;

import java.nio.ByteBuffer;

import org.apache.cassandra.cql3.CQL3Type;
import org.apache.cassandra.cql3.Term;
import org.apache.cassandra.db.context.CounterContext;
import org.apache.cassandra.serializers.TypeSerializer;
import org.apache.cassandra.serializers.CounterSerializer;
import org.apache.cassandra.serializers.MarshalException;
import org.apache.cassandra.transport.ProtocolVersion;
import org.apache.cassandra.utils.ByteBufferUtil;

public class CounterColumnType extends AbstractType<Long>
{
    public static final CounterColumnType instance = new CounterColumnType();

    CounterColumnType() {super(ComparisonType.NOT_COMPARABLE);} // singleton

    public boolean isEmptyValueMeaningless()
    {
        return true;
    }

    public boolean isCounter()
    {
        return true;
    }

    @Override
    public Long compose(ByteBuffer bytes)
    {
        return CounterContext.instance().total(bytes);
    }

    @Override
    public ByteBuffer decompose(Long value)
    {
        return ByteBufferUtil.bytes(value);
    }

    @Override
    public void validateCellValue(ByteBuffer cellValue) throws MarshalException
    {
        CounterContext.instance().validateContext(cellValue);
    }

    public String getString(ByteBuffer bytes)
    {
        return ByteBufferUtil.bytesToHex(bytes);
    }

    public ByteBuffer fromString(String source)
    {
        return ByteBufferUtil.hexToBytes(source);
    }

    @Override
    public Term fromJSONObject(Object parsed)
    {
        throw new UnsupportedOperationException();
    }

    @Override
    public String toJSONString(ByteBuffer buffer, ProtocolVersion protocolVersion)
    {
        return CounterSerializer.instance.deserialize(buffer).toString();
    }

    public CQL3Type asCQL3Type()
    {
        return CQL3Type.Native.COUNTER;
    }

    public TypeSerializer<Long> getSerializer()
    {
        return CounterSerializer.instance;
    }
}