Class LeftBoundFunction<A,T>

java.lang.Object

org.apache.commons.functor.adapter.LeftBoundFunction<A,T>

Type Parameters:

A - the argument type.

T - the returned value type.

All Implemented Interfaces:

Serializable, Functor, UnaryFunction<A,T>, UnaryFunctor<A>

public final class LeftBoundFunction<A,T>
extends Object
implements UnaryFunction<A,T>, Serializable

Adapts a BinaryFunction to the UnaryFunction interface using a constant left-side argument.

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

Version:

$Revision$ $Date$

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private final BinaryFunction<Object, ? super A, ? extends T>	function	The BinaryFunction I'm wrapping.
private final Object	param	The parameter to pass to function.
private static final long	serialVersionUID	serialVersionUID declaration.

Constructor Summary

Constructors

Modifier	Constructor	Description
<L>	LeftBoundFunction(BinaryFunction<? super L, ? super A, ? extends T> function, L arg)	Create a new LeftBoundFunction instance.

Method Summary

Modifier and Type	Method	Description
static <L,R,T> LeftBoundFunction<R,T>	bind(BinaryFunction<? super L, ? super R, ? extends T> function, L arg)	Adapt a BinaryFunction as a UnaryFunction.
boolean	equals(Object that)	Indicates whether some other object is "equal to" this functor.
boolean	equals(LeftBoundFunction<?,?> that)	Learn whether another LeftBoundFunction is equal to this.
T	evaluate(A obj)	Evaluate this function.
int	hashCode()	Returns a hash code for this functor adhering to the general Object.hashCode contract.
String	toString()	Returns a human readable description of this functor.

Methods inherited from class Object

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

Field Details

serialVersionUID

private static final long serialVersionUID

serialVersionUID declaration.

See Also:

• Constant Field Values

function

private final BinaryFunction<Object, ? super A, ? extends T> function

The BinaryFunction I'm wrapping.

param

private final Object param

The parameter to pass to function.

Constructor Details

LeftBoundFunction

public <L> LeftBoundFunction(BinaryFunction<? super L, ? super A, ? extends T> function,
 L arg)

Create a new LeftBoundFunction instance.

Type Parameters:

L - bound arg type

Parameters:

function - the function to adapt

arg - the constant argument to use

Method Details

evaluate

public T evaluate(A obj)

Evaluate this function.

Specified by:

evaluate in interface UnaryFunction<A,T>

Parameters:

obj - the A object to evaluate

Returns:

the T result of this evaluation

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(LeftBoundFunction<?,?> that)

Learn whether another LeftBoundFunction is equal to this.

Parameters:

that - LeftBoundFunction 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(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

bind

public static <L,R,T> LeftBoundFunction<R,T> bind(BinaryFunction<? super L, ? super R, ? extends T> function,
 L arg)

Adapt a BinaryFunction as a UnaryFunction.

Type Parameters:

L - left type

R - right type

T - result type

Parameters:

function - to adapt

arg - left side argument

Returns:

LeftBoundFunction