org.apache.commons.collections4.functors

## Class NullPredicate<T>

- java.lang.Object
- - org.apache.commons.collections4.functors.NullPredicate<T>

- All Implemented Interfaces:
    Serializable, Predicate<T>

      public final class NullPredicate<T>
      extends Object
      implements Predicate<T>, Serializable

  Predicate implementation that returns true if the input is null.
  Since:
    3.0
  See Also:
    Serialized Form

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static Predicate` | `INSTANCE` Singleton predicate instance

  - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `boolean` | `evaluate(T object)` Evaluates the predicate returning true if the input is null.
    `static <T> Predicate<T>` | `nullPredicate()` Factory returning the singleton instance.

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

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Field Detail

    - #### INSTANCE

          public static final Predicate INSTANCE

      Singleton predicate instance

  - ### Method Detail

    - #### nullPredicate

          public static <T> Predicate<T> nullPredicate()

      Factory returning the singleton instance.
      Type Parameters:
        `T` - the type that the predicate queries
      Returns:
        the singleton instance
      Since:
        3.1

    - #### evaluate

          public boolean evaluate(T object)

      Evaluates the predicate returning true if the input is null.
      Specified by:
        `evaluate` in interface `Predicate<T>`
      Parameters:
        `object` - the input object
      Returns:
        true if input is null

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