org.apache.commons.functor.adapter
Class UnaryFunctionUnaryPredicate<A>

java.lang.Object
  org.apache.commons.functor.adapter.UnaryFunctionUnaryPredicate<A>

Type Parameters:

A - the argument type.

All Implemented Interfaces:

Serializable, Functor, UnaryFunctor<A>, UnaryPredicate<A>

public final class UnaryFunctionUnaryPredicate<A>
extends Object
implements UnaryPredicate<A>, Serializable

Adapts a Boolean-valued UnaryFunction to the UnaryPredicate interface.

Note that although this class implements Serializable, a given instance will only be truly Serializable if the underlying function is. Attempts to serialize an instance whose delegate is not Serializable will result in an exception.

Version:

$Revision: 1157648 $ $Date: 2011-08-14 22:22:47 +0200 (Sun, 14 Aug 2011) $

Author:

Rodney Waldhoff

See Also:

Serialized Form

Constructor Summary

UnaryFunctionUnaryPredicate(UnaryFunction<? super A,Boolean> function)
Create an UnaryPredicate wrapping the given UnaryFunction.

Method Summary

static <A> UnaryFunctionUnaryPredicate<A>	adapt(UnaryFunction<? super A,Boolean> function) Adapt the given, possibly-null, UnaryFunction to the UnaryPredicate interface.
boolean	equals(Object that) Indicates whether some other object is "equal to" this functor.
boolean	equals(UnaryFunctionUnaryPredicate<?> that) Learn whether another UnaryFunctionUnaryPredicate is equal to this.
int	hashCode() Returns a hash code for this functor adhering to the general Object.hashCode contract.
boolean	test(A obj) Evaluate this predicate.
String	toString() Returns a human readable description of this functor.

Methods inherited from class java.lang.Object

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

Constructor Detail

UnaryFunctionUnaryPredicate

public UnaryFunctionUnaryPredicate(UnaryFunction<? super A,Boolean> function)

Create an UnaryPredicate wrapping the given UnaryFunction.

Parameters:

function - the UnaryFunction to wrap

Method Detail

test

public boolean test(A obj)

Evaluate this predicate. Returns the boolean value of the non-null Boolean returned by the evaluate method of my underlying function.

Specified by:

test in interface UnaryPredicate<A>

Parameters:

obj - the A object to test

Returns:

the result of this test

equals

public boolean equals(Object that)

Indicates whether some other object is "equal to" this functor. This method must adhere to general Object.equals contract. Additionally, this method can return true only if the specified Object implements the same functor interface and is known to produce the same results and/or side-effects for the same arguments (if any).

While implementators are strongly encouraged to override the default Object implementation of this method, note that the default Object implementation does in fact adhere to the functor equals contract.

Specified by:

equals in interface Functor

Overrides:

equals in class Object

Parameters:

that - the object to compare this functor to

Returns:

true iff the given object implements this functor interface, and is known to produce the same results and/or side-effects for the same arguments (if any).

See Also:

Functor.hashCode()

equals

public boolean equals(UnaryFunctionUnaryPredicate<?> that)

Learn whether another UnaryFunctionUnaryPredicate is equal to this.

Parameters:

that - UnaryFunctionUnaryPredicate to test

Returns:

boolean

hashCode

public int hashCode()

Returns a hash code for this functor adhering to the general Object.hashCode contract. Implementators are strongly encouraged but not strictly required to override the default Object implementation of this method.

Specified by:

hashCode in interface Functor

Overrides:

hashCode in class Object

Returns:

a hash code for this functor

See Also:

Functor.equals(java.lang.Object)

toString

public String toString()

Returns a human readable description of this functor. Implementators are strongly encouraged but not strictly required to override the default Object implementation of this method.

Specified by:

toString in interface Functor

Overrides:

toString in class Object

Returns:

a human readable description of this functor

adapt

public static <A> UnaryFunctionUnaryPredicate<A> adapt(UnaryFunction<? super A,Boolean> function)

Adapt the given, possibly-null, UnaryFunction to the UnaryPredicate interface. When the given UnaryFunction is null, returns null.

Type Parameters:

A - the argument type.

Parameters:

function - the possibly-null UnaryFunction to adapt

Returns:

a UnaryPredicate wrapping the given UnaryFunction, or null if the given UnaryFunction is null