Class SwitchClosure<E>

java.lang.Object

org.apache.commons.collections4.functors.SwitchClosure<E>

All Implemented Interfaces:

Serializable, Closure<E>

public class SwitchClosure<E>
extends Object
implements Closure<E>, Serializable

Closure implementation calls the closure whose predicate returns true, like a switch statement.

Since:

3.0

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private final Closure<? super E>[]	iClosures	The matching closures to call
private final Closure<? super E>	iDefault	The default closure to call if no tests match
private final Predicate<? super E>[]	iPredicates	The tests to consider
private static final long	serialVersionUID	Serial version UID

Constructor Summary

Constructors

Modifier	Constructor	Description
private	SwitchClosure(boolean clone, Predicate<? super E>[] predicates, Closure<? super E>[] closures, Closure<? super E> defaultClosure)	Hidden constructor for the use by the static factory methods.
	SwitchClosure(Predicate<? super E>[] predicates, Closure<? super E>[] closures, Closure<? super E> defaultClosure)	Constructor that performs no validation.

Method Summary

Modifier and Type	Method	Description
void	execute(E input)	Executes the closure whose matching predicate returns true
Closure<? super E>[]	getClosures()	Gets the closures.
Closure<? super E>	getDefaultClosure()	Gets the default closure.
Predicate<? super E>[]	getPredicates()	Gets the predicates.
static <E> Closure<E>	switchClosure(Map<Predicate<E>, Closure<E>> predicatesAndClosures)	Create a new Closure that calls one of the closures depending on the predicates.
static <E> Closure<E>	switchClosure(Predicate<? super E>[] predicates, Closure<? super E>[] closures, Closure<? super E> defaultClosure)	Factory method that performs validation and copies the parameter arrays.

Methods inherited from class Object

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

Field Details

serialVersionUID

private static final long serialVersionUID

Serial version UID

See Also:

• Constant Field Values

iPredicates

private final Predicate<? super E>[] iPredicates

The tests to consider

iClosures

private final Closure<? super E>[] iClosures

The matching closures to call

iDefault

private final Closure<? super E> iDefault

The default closure to call if no tests match

Constructor Details

SwitchClosure

private SwitchClosure(boolean clone,
 Predicate<? super E>[] predicates,
 Closure<? super E>[] closures,
 Closure<? super E> defaultClosure)

Hidden constructor for the use by the static factory methods.

Parameters:

clone - if true the input arguments will be cloned

predicates - array of predicates, no nulls

closures - matching array of closures, no nulls

defaultClosure - the closure to use if no match, null means nop

SwitchClosure

public SwitchClosure(Predicate<? super E>[] predicates,
 Closure<? super E>[] closures,
 Closure<? super E> defaultClosure)

Constructor that performs no validation. Use switchClosure if you want that.

Parameters:

predicates - array of predicates, cloned, no nulls

closures - matching array of closures, cloned, no nulls

defaultClosure - the closure to use if no match, null means nop

Method Details

switchClosure

public static <E> Closure<E> switchClosure(Predicate<? super E>[] predicates,
 Closure<? super E>[] closures,
 Closure<? super E> defaultClosure)

Factory method that performs validation and copies the parameter arrays.

Type Parameters:

E - the type that the closure acts on

Parameters:

predicates - array of predicates, cloned, no nulls

closures - matching array of closures, cloned, no nulls

defaultClosure - the closure to use if no match, null means nop

Returns:

the chained closure

Throws:

NullPointerException - if array is null

NullPointerException - if any element in the array is null

IllegalArgumentException - if the array lengths of predicates and closures do not match

switchClosure

public static <E> Closure<E> switchClosure(Map<Predicate<E>, Closure<E>> predicatesAndClosures)

Create a new Closure that calls one of the closures depending on the predicates.

The Map consists of Predicate keys and Closure values. A closure is called if its matching predicate returns true. Each predicate is evaluated until one returns true. If no predicates evaluate to true, the default closure is called. The default closure is set in the map with a null key. The ordering is that of the iterator() method on the entryset collection of the map.

Type Parameters:

E - the type that the closure acts on

Parameters:

predicatesAndClosures - a map of predicates to closures

Returns:

the switch closure

Throws:

NullPointerException - if the map is null

NullPointerException - if any closure in the map is null

ClassCastException - if the map elements are of the wrong type

execute

public void execute(E input)

Executes the closure whose matching predicate returns true

Specified by:

execute in interface Closure<E>

Parameters:

input - the input object

getPredicates

public Predicate<? super E>[] getPredicates()

Gets the predicates.

Returns:

a copy of the predicates

Since:

3.1

getClosures

public Closure<? super E>[] getClosures()

Gets the closures.

Returns:

a copy of the closures

Since:

3.1

getDefaultClosure

public Closure<? super E> getDefaultClosure()

Gets the default closure.

Returns:

the default closure

Since:

3.1