Package org.apache.commons.lang3
Class ObjectUtils.Null
java.lang.Object
org.apache.commons.lang3.ObjectUtils.Null
- All Implemented Interfaces:
Serializable
- Enclosing class:
- ObjectUtils
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:
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Field Summary
FieldsModifier and TypeFieldDescriptionprivate static final long
Required for serialization support. -
Constructor Summary
Constructors -
Method Summary
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Field Details
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serialVersionUID
private static final long serialVersionUIDRequired for serialization support. Declare serialization compatibility with Commons Lang 1.0- See Also:
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Constructor Details
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Null
Null()Restricted constructor - singleton.
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Method Details
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readResolve
Ensure singleton.
- Returns:
- the singleton value
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