org.apache.commons.functor.core
Class LeftIdentity

java.lang.Object
  org.apache.commons.functor.core.LeftIdentity

public final class LeftIdentity
extends Object

Holder class for a left-identity BinaryFunction (evaluates to the left argument) and a left-identity BinaryPredicate (tests whether left Boolean argument equals Boolean.TRUE).

Version:

$Revision: 1160411 $ $Date: 2011-08-22 22:09:01 +0200 (Mon, 22 Aug 2011) $

Author:

Rodney Waldhoff, Matt Benson

Field Summary

static BinaryFunction<Object,Object,Object>	FUNCTION Left-identity function.
static BinaryPredicate<Boolean,Object>	PREDICATE Left-identity predicate.

Constructor Summary

LeftIdentity()
Create a new LeftIdentity (for clients that require an object).

Method Summary

static <L,R> BinaryFunction<L,R,L>	function() Get a Left-identity BinaryFunction.
static <R> BinaryPredicate<Boolean,R>	predicate() Get a left-identity BinaryPredicate.

Methods inherited from class java.lang.Object

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

Field Detail

FUNCTION

public static final BinaryFunction<Object,Object,Object> FUNCTION

Left-identity function.

PREDICATE

public static final BinaryPredicate<Boolean,Object> PREDICATE

Left-identity predicate.

Constructor Detail

LeftIdentity

public LeftIdentity()

Create a new LeftIdentity (for clients that require an object).

Method Detail

function

public static <L,R> BinaryFunction<L,R,L> function()

Get a Left-identity BinaryFunction.

Type Parameters:

L - the left argument type.

R - the right argument type.

Returns:

BinaryFunction

predicate

public static <R> BinaryPredicate<Boolean,R> predicate()

Get a left-identity BinaryPredicate.

Type Parameters:

R - the right argument type.

Returns:

BinaryPredicate