content: /*
   * 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 com.aliyun.odps.io;
  
  /**
   * DateWritable 提供了 date 的 {@link Writable} 和 {@link WritableComparable}
   * 的实现。
   */
  public class DateWritable extends AbstractDatetimeWritable<DateWritable> {
  
    /**
     * 默认构造 datetime 值为0的 DatetimeWritable.
     */
    public DateWritable() {
    }
  
    /**
     * 构造 long 值为给定 value 的 DatetimeWritable.
     *
     * @param value
     */
    public DateWritable(long value) {
      super(value);
    }
  
    /**
     * 获取该writable对应的 java.sql.Date 对象
     */
    public java.sql.Date getDate() {
      return new java.sql.Date(get());
    }
  
    /**
     * DatetimeWritable 对象的 {@link WritableComparator} 自然顺序实现（升序）.
     */
    public static class Comparator extends WritableComparator {
  
      public Comparator() {
        super(DateWritable.class);
      }
  
      /**
       * 基于二进制内容的 DatetimeWritable 对象比较函数.
       */
      @Override
      public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
        long thisValue = readLong(b1, s1);
        long thatValue = readLong(b2, s2);
        return (thisValue < thatValue ? -1 : (thisValue == thatValue ? 0 : 1));
      }
    }
  
    /**
     * DatetimeWritable 对象的 {@link WritableComparator} 降序实现.
     */
    public static class DecreasingComparator extends Comparator {
  
      @Override
      public int compare(WritableComparable a, WritableComparable b) {
        return -super.compare(a, b);
      }
  
      @Override
      public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
        return -super.compare(b1, s1, l1, b2, s2, l2);
      }
    }
  
    static { // register default comparator
      WritableComparator.define(DateWritable.class, new Comparator());
    }
  
  }
  