org.apache.commons.functor.core.comparator
Class ComparatorFunction<T>

java.lang.Object
  org.apache.commons.functor.core.comparator.ComparatorFunction<T>

All Implemented Interfaces:

Serializable, BinaryFunction<T,T,Integer>, BinaryFunctor<T,T>, Functor

public final class ComparatorFunction<T>
extends Object
implements BinaryFunction<T,T,Integer>, Serializable

Adapts a Comparator to the BinaryFunction interface.

Version:

$Revision: 1156349 $ $Date: 2011-08-10 22:21:14 +0200 (Wed, 10 Aug 2011) $

Author:

Rodney Waldhoff

See Also:

Serialized Form

Field Summary

static ComparatorFunction<Comparable<?>>

INSTANCE Basic ComparatorFunction instance.

Constructor Summary

ComparatorFunction(Comparator<? super T> comparator)
Create a new ComparatorFunction.

Method Summary

boolean	equals(ComparatorFunction<?> that) Learn whether a specified ComparatorFunction is equal to this.
boolean	equals(Object that) Indicates whether some other object is "equal to" this functor.
Integer	evaluate(T left, T right) Evaluate this function.
int	hashCode() Returns a hash code for this functor adhering to the general Object.hashCode contract.
static <T> ComparatorFunction<T>	instance() Get a basic ComparatorFunction instance.
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

Field Detail

INSTANCE

public static final ComparatorFunction<Comparable<?>> INSTANCE

Basic ComparatorFunction instance.

Constructor Detail

ComparatorFunction

public ComparatorFunction(Comparator<? super T> comparator)

Create a new ComparatorFunction.

Parameters:

comparator - to wrap

Method Detail

evaluate

public Integer evaluate(T left,
                        T right)

Evaluate this function.

Specified by:

evaluate in interface BinaryFunction<T,T,Integer>

Parameters:

left - the L element of the ordered pair of arguments

right - the R element of the ordered pair of arguments

Returns:

the T result of this function for the given arguments

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(ComparatorFunction<?> that)

Learn whether a specified ComparatorFunction is equal to this.

Parameters:

that - the ComparatorFunction 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

instance

public static <T> ComparatorFunction<T> instance()

Get a basic ComparatorFunction instance.

Returns:

ComparatorFunction