hadoop DoubleWritable 源码

  • 2022-10-20
  • 浏览 (328)

haddop DoubleWritable 代码

文件路径:/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/io/DoubleWritable.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.hadoop.io;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;

/**
 * Writable for Double values.
 */
@InterfaceAudience.Public
@InterfaceStability.Stable
public class DoubleWritable implements WritableComparable<DoubleWritable> {

  private double value = 0.0;
  
  public DoubleWritable() {
    
  }
  
  public DoubleWritable(double value) {
    set(value);
  }
  
  @Override
  public void readFields(DataInput in) throws IOException {
    value = in.readDouble();
  }

  @Override
  public void write(DataOutput out) throws IOException {
    out.writeDouble(value);
  }
  
  public void set(double value) { this.value = value; }
  
  public double get() { return value; }

  /**
   * Returns true iff <code>o</code> is a DoubleWritable with the same value.
   */
  @Override
  public boolean equals(Object o) {
    if (!(o instanceof DoubleWritable)) {
      return false;
    }
    DoubleWritable other = (DoubleWritable)o;
    return this.value == other.value;
  }
  
  @Override
  public int hashCode() {
    return (int)Double.doubleToLongBits(value);
  }
  
  @Override
  public int compareTo(DoubleWritable o) {
    return Double.compare(value, o.value);
  }
  
  @Override
  public String toString() {
    return Double.toString(value);
  }

  /** A Comparator optimized for DoubleWritable. */ 
  public static class Comparator extends WritableComparator {
    public Comparator() {
      super(DoubleWritable.class);
    }

    @Override
    public int compare(byte[] b1, int s1, int l1,
                       byte[] b2, int s2, int l2) {
      double thisValue = readDouble(b1, s1);
      double thatValue = readDouble(b2, s2);
      return Double.compare(thisValue, thatValue);
    }
  }

  static {                                        // register this comparator
    WritableComparator.define(DoubleWritable.class, new Comparator());
  }

}

相关信息

hadoop 源码目录

相关文章

hadoop AbstractMapWritable 源码

hadoop ArrayFile 源码

hadoop ArrayPrimitiveWritable 源码

hadoop ArrayWritable 源码

hadoop BinaryComparable 源码

hadoop BloomMapFile 源码

hadoop BooleanWritable 源码

hadoop BoundedByteArrayOutputStream 源码

hadoop ByteBufferPool 源码

hadoop ByteWritable 源码

0  赞