001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase;
019
020import java.nio.ByteBuffer;
021import org.apache.hadoop.hbase.util.ByteBufferUtils;
022import org.apache.yetus.audience.InterfaceAudience;
023import org.apache.yetus.audience.InterfaceStability;
024
025/**
026 * This is a {@link Tag} implementation in which value is backed by {@link java.nio.ByteBuffer}
027 */
028@InterfaceAudience.Private
029@InterfaceStability.Evolving
030public class ByteBufferTag implements Tag {
031
032  private ByteBuffer buffer;
033  private int offset, length;
034  private byte type;
035
036  public ByteBufferTag(ByteBuffer buffer, int offset, int length) {
037    this.buffer = buffer;
038    this.offset = offset;
039    this.length = length;
040    this.type = ByteBufferUtils.toByte(buffer, offset + TAG_LENGTH_SIZE);
041  }
042
043  @Override
044  public byte getType() {
045    return this.type;
046  }
047
048  @Override
049  public int getValueOffset() {
050    return this.offset + INFRASTRUCTURE_SIZE;
051  }
052
053  @Override
054  public int getValueLength() {
055    return this.length - INFRASTRUCTURE_SIZE;
056  }
057
058  @Override
059  public boolean hasArray() {
060    return false;
061  }
062
063  @Override
064  public byte[] getValueArray() {
065    throw new UnsupportedOperationException(
066      "Tag is backed by an off heap buffer. Use getValueByteBuffer()");
067  }
068
069  @Override
070  public ByteBuffer getValueByteBuffer() {
071    return this.buffer;
072  }
073
074  @Override
075  public String toString() {
076    return "[Tag type : " + this.type + ", value : "
077      + ByteBufferUtils.toStringBinary(buffer, getValueOffset(), getValueLength()) + "]";
078  }
079}