Package org.apache.commons.lang3
Class ObjectUtils.Null
- java.lang.Object
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- org.apache.commons.lang3.ObjectUtils.Null
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- 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
theHashMap.get(java.lang.Object)
method returnsnull
if theMap
containsnull
or if there is no matching key. TheNull
placeholder can be used to distinguish between these two cases.Another example is
Hashtable
, wherenull
cannot be stored.- See Also:
- Serialized Form
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Field Summary
Fields Modifier and Type Field Description private static long
serialVersionUID
Required for serialization support.
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Constructor Summary
Constructors Constructor Description Null()
Restricted constructor - singleton.
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description private java.lang.Object
readResolve()
Ensure singleton.
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Field Detail
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serialVersionUID
private static final long serialVersionUID
Required for serialization support. Declare serialization compatibility with Commons Lang 1.0- See Also:
Serializable
, Constant Field Values
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