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 */
018
019package org.apache.hadoop.io;
020
021import java.io.*;
022
023import org.apache.hadoop.classification.InterfaceAudience;
024import org.apache.hadoop.classification.InterfaceStability;
025
026/** A WritableComparable for longs in a variable-length format. Such values take
027 *  between one and five bytes.  Smaller values take fewer bytes.
028 *  
029 *  @see org.apache.hadoop.io.WritableUtils#readVLong(DataInput)
030 */
031@InterfaceAudience.Public
032@InterfaceStability.Stable
033public class VLongWritable implements WritableComparable<VLongWritable> {
034  private long value;
035
036  public VLongWritable() {}
037
038  public VLongWritable(long value) { set(value); }
039
040  /** Set the value of this LongWritable. */
041  public void set(long value) { this.value = value; }
042
043  /** Return the value of this LongWritable. */
044  public long get() { return value; }
045
046  public void readFields(DataInput in) throws IOException {
047    value = WritableUtils.readVLong(in);
048  }
049
050  public void write(DataOutput out) throws IOException {
051    WritableUtils.writeVLong(out, value);
052  }
053
054  /** Returns true iff <code>o</code> is a VLongWritable with the same value. */
055  @Override
056  public boolean equals(Object o) {
057    if (!(o instanceof VLongWritable))
058      return false;
059    VLongWritable other = (VLongWritable)o;
060    return this.value == other.value;
061  }
062
063  @Override
064  public int hashCode() {
065    return (int)value;
066  }
067
068  /** Compares two VLongWritables. */
069  @Override
070  public int compareTo(VLongWritable o) {
071    long thisValue = this.value;
072    long thatValue = o.value;
073    return (thisValue < thatValue ? -1 : (thisValue == thatValue ? 0 : 1));
074  }
075
076  @Override
077  public String toString() {
078    return Long.toString(value);
079  }
080
081}
082