Null.java

/*
   Copyright (c) 2012 LinkedIn Corp.

   Licensed 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.linkedin.data;


/**
 * Represent NULL value in DataMap.
 */
@SuppressWarnings({"overrides"}) //for hashCode/equals contract
public final class Null
{
  private static final Null INSTANCE = new Null();

  public static final Null getInstance()
  {
    return INSTANCE;
  }

  private Null()
  {
  }

  public boolean equals(Object o)
  {
    return o == INSTANCE;
  }

  public String toString()
  {
    return "null";
  }
}