broker-plugins/amqp-1-0-protocol/src/main/java/org/apache/qpid/server/protocol/v1_0/codec/SmallULongConstructor.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.qpid.server.protocol.v1_0.codec;

import org.apache.qpid.server.bytebuffer.QpidByteBuffer;
import org.apache.qpid.server.protocol.v1_0.type.AmqpErrorException;
import org.apache.qpid.server.protocol.v1_0.type.UnsignedLong;
import org.apache.qpid.server.protocol.v1_0.type.transport.AmqpError;

public class SmallULongConstructor implements TypeConstructor<UnsignedLong>
{
    private static final SmallULongConstructor INSTANCE = new SmallULongConstructor();


    public static SmallULongConstructor getInstance()
    {
        return INSTANCE;
    }

    private SmallULongConstructor()
    {
    }

    @Override
    public UnsignedLong construct(final QpidByteBuffer in, final ValueHandler handler) throws AmqpErrorException
    {
        if (in.hasRemaining())
        {
            byte b = in.get();
            return UnsignedLong.valueOf(((long) b) & 0xffL);
        }
        else
        {
            throw new AmqpErrorException(AmqpError.DECODE_ERROR, "Cannot construct ulong: insufficient input data");
        }
    }
}