net.sf.collections15.functors.predicate
Class TransformerPredicate<E>

java.lang.Object
  net.sf.collections15.functors.predicate.TransformerPredicate<E>

All Implemented Interfaces:

java.io.Serializable, Predicate<E>

public final class TransformerPredicate<E>
extends java.lang.Object
implements Predicate<E>, java.io.Serializable

Predicate implementation that wraps a Transformer whose output type is Boolean. The Predicate evaluates true if the Transformer returns Boolean.TRUE, and evaluates to false if the Transformer returns Boolean.False or null.

Since:

Collections15 1.0

Author:

Stephen Colebourne, Chris Lambrou (port to Java 5.0)

See Also:

Serialized Form

Constructor Summary

protected

TransformerPredicate(Transformer<E,java.lang.Boolean> transformer) Creates a new instance that evaluates input objects using the specified Transformer.

Method Summary

boolean	evaluate(E object) Evaluates the Predicate returning the result of the wrapped Transformer.
static <T> Predicate<T>	getInstance(Transformer<T,java.lang.Boolean> transformer) Returns an instance that evaluates input objects using the specified Transformer.
Transformer<E,java.lang.Boolean>	getTransformer() Returns the underlying Transformer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TransformerPredicate

protected TransformerPredicate(Transformer<E,java.lang.Boolean> transformer)

Creates a new instance that evaluates input objects using the specified Transformer.

Parameters:

transformer - The Transformer to use.

Throws:

java.lang.IllegalArgumentException - Thrown if the transformer argument is null.

Method Detail

getInstance

public static <T> Predicate<T> getInstance(Transformer<T,java.lang.Boolean> transformer)

Returns an instance that evaluates input objects using the specified Transformer.

Parameters:

transformer - The Transformer to use.

Returns:

A Predicate that evaluates input objects using the specified Transformer.

Throws:

java.lang.IllegalArgumentException - Thrown if the transformer argument is null.

evaluate

public boolean evaluate(E object)

Evaluates the Predicate returning the result of the wrapped Transformer.

Specified by:

evaluate in interface Predicate<E>

Parameters:

object - The input object yo evaluate.

Returns:

true if the underlying Transformer returns Boolean.TRUE. false if the underlying Transformer returns Boolean.FALSE or null.

getTransformer

public Transformer<E,java.lang.Boolean> getTransformer()

Returns the underlying Transformer.

Returns:

The underlying Transformer.

Since:

Collections15 1.0