org.apache.tinkerpop.gremlin.process.computer

## Class MapReduce.NullObject

- java.lang.Object
- - org.apache.tinkerpop.gremlin.process.computer.MapReduce.NullObject

- All Implemented Interfaces:
    Serializable, Comparable<MapReduce.NullObject>
  Enclosing interface:
    MapReduce<MK,MV,RK,RV,R>

      public static class MapReduce.NullObject
      extends Object
      implements Comparable<MapReduce.NullObject>, Serializable

  A convenience singleton when a single key is needed so that all emitted values converge to the same combiner/reducer.
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `NullObject()`

  - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `int` | `compareTo(MapReduce.NullObject object)`
    `boolean` | `equals(Object object)`
    `int` | `hashCode()`
    `static MapReduce.NullObject` | `instance()`
    `String` | `toString()`

    - ### Methods inherited from class java.lang.Object

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### NullObject

          public NullObject()

  - ### Method Detail

    - #### instance

          public static MapReduce.NullObject instance()

    - #### hashCode

          public int hashCode()

      Overrides:
        `hashCode` in class `Object`

    - #### equals

          public boolean equals(Object object)

      Overrides:
        `equals` in class `Object`

    - #### compareTo

          public int compareTo(MapReduce.NullObject object)

      Specified by:
        `compareTo` in interface `Comparable<MapReduce.NullObject>`

    - #### toString

          public String toString()

      Overrides:
        `toString` in class `Object`

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