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.DataInput; 022import java.io.DataOutput; 023import java.io.IOException; 024 025import org.apache.hadoop.classification.InterfaceAudience; 026import org.apache.hadoop.classification.InterfaceStability; 027 028/** A WritableComparable for shorts. */ 029@InterfaceAudience.Public 030@InterfaceStability.Stable 031public class ShortWritable implements WritableComparable<ShortWritable> { 032 private short value; 033 034 public ShortWritable() { 035 } 036 037 public ShortWritable(short value) { 038 set(value); 039 } 040 041 /** Set the value of this ShortWritable. */ 042 public void set(short value) { 043 this.value = value; 044 } 045 046 /** Return the value of this ShortWritable. */ 047 public short get() { 048 return value; 049 } 050 051 /** read the short value */ 052 @Override 053 public void readFields(DataInput in) throws IOException { 054 value = in.readShort(); 055 } 056 057 /** write short value */ 058 @Override 059 public void write(DataOutput out) throws IOException { 060 out.writeShort(value); 061 } 062 063 /** Returns true iff <code>o</code> is a ShortWritable with the same value. */ 064 @Override 065 public boolean equals(Object o) { 066 if (!(o instanceof ShortWritable)) 067 return false; 068 ShortWritable other = (ShortWritable) o; 069 return this.value == other.value; 070 } 071 072 /** hash code */ 073 @Override 074 public int hashCode() { 075 return value; 076 } 077 078 /** Compares two ShortWritable. */ 079 @Override 080 public int compareTo(ShortWritable o) { 081 short thisValue = this.value; 082 short thatValue = (o).value; 083 return (thisValue < thatValue ? -1 : (thisValue == thatValue ? 0 : 1)); 084 } 085 086 /** Short values in string format */ 087 @Override 088 public String toString() { 089 return Short.toString(value); 090 } 091 092 /** A Comparator optimized for ShortWritable. */ 093 public static class Comparator extends WritableComparator { 094 095 public Comparator() { 096 super(ShortWritable.class); 097 } 098 099 @Override 100 public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) { 101 short thisValue = (short) readUnsignedShort(b1, s1); 102 short thatValue = (short) readUnsignedShort(b2, s2); 103 return (thisValue < thatValue ? -1 : (thisValue == thatValue ? 0 : 1)); 104 } 105 } 106 107 static { // register this comparator 108 WritableComparator.define(ShortWritable.class, new Comparator()); 109 } 110 111}