Package com.tangosol.util
Class NullImplementation.NullValueExtractor
java.lang.Object
com.tangosol.util.NullImplementation.NullValueExtractor
- All Implemented Interfaces:
CanonicallyNamed
,ExternalizableLite
,PortableObject
,Remote.Function
,Remote.ToDoubleFunction
,Remote.ToIntFunction
,Remote.ToLongFunction
,ValueExtractor
,Serializable
,Function
,ToDoubleFunction
,ToIntFunction
,ToLongFunction
- Enclosing class:
NullImplementation
public static class NullImplementation.NullValueExtractor
extends Object
implements ValueExtractor, Serializable, ExternalizableLite, PortableObject
A ValueExtractor that always results in the passed-in value.
- See Also:
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Field Summary
Modifier and TypeFieldDescriptionstatic final NullImplementation.NullValueExtractor
Since the ValueExtractor contains no information, only one ever has to exist. -
Constructor Summary
ConstructorDescriptionDefault constructor (for ExternalizableLite and PortableObject). -
Method Summary
Modifier and TypeMethodDescriptionboolean
Compare the ValueExtractor with another object to determine equality.Extract the value from the passed object.int
hashCode()
Determine a hash value for the ValueExtractor object according to the generalObject.hashCode()
contract.void
Restore the contents of a user type instance by reading its state using the specified PofReader object.void
Restore the contents of this object by loading the object's state from the passed DataInput object.toString()
Provide a human-readable description of this ValueExtractor object.void
writeExternal
(PofWriter out) Save the contents of a POF user type instance by writing its state using the specified PofWriter object.void
writeExternal
(DataOutput out) Save the contents of this object by storing the object's state into the passed DataOutput object.Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
Methods inherited from interface com.tangosol.util.function.Remote.Function
andThen, compose
Methods inherited from interface com.tangosol.util.ValueExtractor
andThen, apply, applyAsDouble, applyAsInt, applyAsLong, compose, fromKey, getCanonicalName, getTarget
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Field Details
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INSTANCE
Since the ValueExtractor contains no information, only one ever has to exist.
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Constructor Details
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NullValueExtractor
public NullValueExtractor()Default constructor (for ExternalizableLite and PortableObject).
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Method Details
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extract
Extract the value from the passed object. The returned value may be null. For intrinsic types, the returned value is expected to be a standard wrapper type in the same manner that reflection works; for example, int would be returned as a java.lang.Integer.- Specified by:
extract
in interfaceValueExtractor
- Parameters:
o
- the object to extract the value from- Returns:
- the extracted value as an Object; null is an acceptable value
- Throws:
ClassCastException
- if this ValueExtractor is incompatible with the passed object to extract a value from and the implementation requires the passed object to be of a certain typeWrapperException
- if this ValueExtractor encounters an exception in the course of extracting the valueIllegalArgumentException
- if this ValueExtractor cannot handle the passed object for any other reason; an implementor should include a descriptive message
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equals
Compare the ValueExtractor with another object to determine equality. Two ValueExtractor objects, ve1 and ve2 are considered equal iff ve1.extract(o) equals ve2.extract(o) for all values of o.- Specified by:
equals
in interfaceValueExtractor
- Overrides:
equals
in classObject
- Returns:
- true iff this ValueExtractor and the passed object are equivalent ValueExtractors
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hashCode
public int hashCode()Determine a hash value for the ValueExtractor object according to the generalObject.hashCode()
contract.- Specified by:
hashCode
in interfaceValueExtractor
- Overrides:
hashCode
in classObject
- Returns:
- an integer hash value for this ValueExtractor object
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toString
Provide a human-readable description of this ValueExtractor object. -
readExternal
Restore the contents of this object by loading the object's state from the passed DataInput object.- Specified by:
readExternal
in interfaceExternalizableLite
- Parameters:
in
- the DataInput stream to read data from in order to restore the state of this object- Throws:
IOException
- if an I/O exception occurs
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writeExternal
Save the contents of this object by storing the object's state into the passed DataOutput object.- Specified by:
writeExternal
in interfaceExternalizableLite
- Parameters:
out
- the DataOutput stream to write the state of this object to- Throws:
IOException
- if an I/O exception occurs
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readExternal
Restore the contents of a user type instance by reading its state using the specified PofReader object.- Specified by:
readExternal
in interfacePortableObject
- Parameters:
in
- the PofReader from which to read the object's state- Throws:
IOException
- if an I/O error occurs
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writeExternal
Save the contents of a POF user type instance by writing its state using the specified PofWriter object.- Specified by:
writeExternal
in interfacePortableObject
- Parameters:
out
- the PofWriter to which to write the object's state- Throws:
IOException
- if an I/O error occurs
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