public static class NullImplementation.NullValueExtractor extends Object implements ValueExtractor, Serializable, ExternalizableLite, PortableObject
Modifier and Type | Field and Description |
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static NullImplementation.NullValueExtractor |
INSTANCE
Since the ValueExtractor contains no information, only one ever has to
exist.
|
Constructor and Description |
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NullValueExtractor()
Default constructor (for ExternalizableLite and PortableObject).
|
Modifier and Type | Method and Description |
---|---|
boolean |
equals(Object o)
Compare the ValueExtractor with another object to determine equality.
|
Object |
extract(Object o)
Extract the value from the passed object.
|
int |
hashCode()
Determine a hash value for the ValueExtractor object according to the
general
Object.hashCode() contract. |
void |
readExternal(DataInput in)
Restore the contents of this object by loading the object's state from
the passed DataInput object.
|
void |
readExternal(PofReader in)
Restore the contents of a user type instance by reading its state using
the specified PofReader object.
|
String |
toString()
Provide a human-readable description of this ValueExtractor object.
|
void |
writeExternal(DataOutput out)
Save the contents of this object by storing the object's state into
the passed DataOutput object.
|
void |
writeExternal(PofWriter out)
Save the contents of a POF user type instance by writing its state using
the specified PofWriter object.
|
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
andThen, apply, applyAsDouble, applyAsInt, applyAsLong, compose, fromKey, getCanonicalName, getTarget, identity, identityCast, of
andThen, compose
public static final NullImplementation.NullValueExtractor INSTANCE
public NullValueExtractor()
public Object extract(Object o)
extract
in interface ValueExtractor
o
- the object to extract the value fromClassCastException
- 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 messagepublic boolean equals(Object o)
equals
in interface ValueExtractor
equals
in class Object
public int hashCode()
Object.hashCode()
contract.hashCode
in interface ValueExtractor
hashCode
in class Object
public String toString()
public void readExternal(DataInput in) throws IOException
readExternal
in interface ExternalizableLite
in
- the DataInput stream to read data from in order to restore
the state of this objectIOException
- if an I/O exception occursNotActiveException
- if the object is not in its initial
state, and therefore cannot be deserialized intopublic void writeExternal(DataOutput out) throws IOException
writeExternal
in interface ExternalizableLite
out
- the DataOutput stream to write the state of this object toIOException
- if an I/O exception occurspublic void readExternal(PofReader in) throws IOException
readExternal
in interface PortableObject
in
- the PofReader from which to read the object's stateIOException
- if an I/O error occurspublic void writeExternal(PofWriter out) throws IOException
writeExternal
in interface PortableObject
out
- the PofWriter to which to write the object's stateIOException
- if an I/O error occurs