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## org.apache.commons.lang
Class ObjectUtils.Null

    java.lang.Object
      org.apache.commons.lang.ObjectUtils.Null

All Implemented Interfaces:
  java.io.Serializable

Enclosing class:
  ObjectUtils

public static class ObjectUtils.Null
extends java.lang.Object
implements java.io.Serializable

Class used as a null placeholder where `null` has another meaning.

For example, in a `HashMap` the `HashMap.get(java.lang.Object)` method returns `null` if the `Map` contains `null` or if there is no matching key. The `Null` placeholder can be used to distinguish between these two cases.

Another example is `Hashtable`, where `null` cannot be stored.

See Also:
  Serialized Form

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

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