com.hazelcast.query.impl

Class FalsePredicate<K,V>

java.lang.Object

com.hazelcast.query.impl.FalsePredicate<K,V>

All Implemented Interfaces:

DataSerializable, IdentifiedDataSerializable, IndexAwarePredicate<K,V>, Predicate<K,V>, Serializable

public class FalsePredicate<K,V>
extends Object
implements IdentifiedDataSerializable, Predicate<K,V>, IndexAwarePredicate<K,V>

A Predicate which always returns false.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static FalsePredicate	INSTANCE An instance of the FalsePredicate.

Constructor Summary

Constructors

Constructor and Description
FalsePredicate()

Method Summary

Modifier and Type	Method and Description
boolean	apply(Map.Entry<K,V> mapEntry) Applies this predicate to the given map entry.
boolean	equals(Object o)
Set<QueryableEntry<K,V>>	filter(QueryContext queryContext) Produces a filtered entry set by utilizing the indexes available while executing the query in the given query context.
int	getFactoryId() Returns DataSerializableFactory factory ID for this class.
int	getId() Returns type identifier for this class.
int	hashCode()
boolean	isIndexed(QueryContext queryContext) Signals to the query engine that this predicate is able to utilize the indexes available while executing the query in the given query context.
void	readData(ObjectDataInput in) Reads fields from the input stream
String	toString()
void	writeData(ObjectDataOutput out) Writes object fields to output stream

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

INSTANCE

public static final FalsePredicate INSTANCE

An instance of the FalsePredicate.

Constructor Detail

FalsePredicate

public FalsePredicate()

Method Detail

apply

public boolean apply(Map.Entry<K,V> mapEntry)

Description copied from interface: Predicate

Applies this predicate to the given map entry.

Implementations must be thread-safe, since this method may be called by multiple threads concurrently.

Specified by:

apply in interface Predicate<K,V>

Parameters:

mapEntry - the map entry to apply this predicate to.

Returns:

true if the given map entry matches this predicate, false otherwise.

toString

public String toString()

Overrides:

toString in class Object

filter

public Set<QueryableEntry<K,V>> filter(QueryContext queryContext)

Description copied from interface: IndexAwarePredicate

Produces a filtered entry set by utilizing the indexes available while executing the query in the given query context.

The query engine assumes this method produces the result set faster than a simple evaluation of the predicate on every entry.

Specified by:

filter in interface IndexAwarePredicate<K,V>

Parameters:

queryContext - the query context to access the indexes. The passed query context is valid only for a duration of a single call to the method.

Returns:

the produced filtered entry set.

isIndexed

public boolean isIndexed(QueryContext queryContext)

Description copied from interface: IndexAwarePredicate

Signals to the query engine that this predicate is able to utilize the indexes available while executing the query in the given query context.

Specified by:

isIndexed in interface IndexAwarePredicate<K,V>

Parameters:

queryContext - the query context to consult for the available indexes.

Returns:

true if this predicate is able to use the indexes to speed up the processing, false otherwise.

writeData

public void writeData(ObjectDataOutput out)
               throws IOException

Description copied from interface: DataSerializable

Writes object fields to output stream

Specified by:

writeData in interface DataSerializable

Parameters:

out - output

Throws:

IOException - if an I/O error occurs. In particular, an IOException may be thrown if the output stream has been closed.

readData

public void readData(ObjectDataInput in)
              throws IOException

Description copied from interface: DataSerializable

Reads fields from the input stream

Specified by:

readData in interface DataSerializable

Parameters:

in - input

Throws:

IOException - if an I/O error occurs. In particular, an IOException may be thrown if the input stream has been closed.

getFactoryId

public int getFactoryId()

Description copied from interface: IdentifiedDataSerializable

Returns DataSerializableFactory factory ID for this class.

Specified by:

getFactoryId in interface IdentifiedDataSerializable

Returns:

factory ID

getId

public int getId()

Description copied from interface: IdentifiedDataSerializable

Returns type identifier for this class. It should be unique per DataSerializableFactory.

Specified by:

getId in interface IdentifiedDataSerializable

Returns:

type ID

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object