Java tutorial
/** * 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.hadoop.io; import java.io.*; import org.apache.hadoop.classification.InterfaceAudience; import org.apache.hadoop.classification.InterfaceStability; /** * A WritableComparable for booleans. */ @InterfaceAudience.Public @InterfaceStability.Stable public class BooleanWritable implements WritableComparable<BooleanWritable> { private boolean value; /** */ public BooleanWritable() { }; /** */ public BooleanWritable(boolean value) { set(value); } /** * Set the value of the BooleanWritable */ public void set(boolean value) { this.value = value; } /** * Returns the value of the BooleanWritable */ public boolean get() { return value; } /** */ @Override public void readFields(DataInput in) throws IOException { value = in.readBoolean(); } /** */ @Override public void write(DataOutput out) throws IOException { out.writeBoolean(value); } /** */ @Override public boolean equals(Object o) { if (!(o instanceof BooleanWritable)) { return false; } BooleanWritable other = (BooleanWritable) o; return this.value == other.value; } @Override public int hashCode() { return value ? 0 : 1; } /** */ @Override public int compareTo(BooleanWritable o) { boolean a = this.value; boolean b = o.value; return ((a == b) ? 0 : (a == false) ? -1 : 1); } @Override public String toString() { return Boolean.toString(get()); } /** * A Comparator optimized for BooleanWritable. */ public static class Comparator extends WritableComparator { public Comparator() { super(BooleanWritable.class); } @Override public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) { return compareBytes(b1, s1, l1, b2, s2, l2); } } static { WritableComparator.define(BooleanWritable.class, new Comparator()); } }