Package org.apache.commons.collections.functors

Class SwitchClosure

java.lang.Object
org.apache.commons.collections.functors.SwitchClosure
All Implemented Interfaces:
Serializable, Closure
public class SwitchClosure extends Object implements Closure, Serializable
Closure implementation calls the closure whose predicate returns true, like a switch statement.
Since:
Commons Collections 3.0
Version:
$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $
Author:
Stephen Colebourne
See Also:

  • Constructor Details

    • SwitchClosure

      public SwitchClosure(Predicate[] predicates, Closure[] closures, Closure defaultClosure)
      Constructor that performs no validation. Use getInstance if you want that.
      Parameters:
      predicates - array of predicates, not cloned, no nulls
      closures - matching array of closures, not cloned, no nulls
      defaultClosure - the closure to use if no match, null means nop

  • Method Details

    • getInstance

      public static Closure getInstance(Predicate[] predicates, Closure[] closures, Closure defaultClosure)
      Factory method that performs validation and copies the parameter arrays.
      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:
      IllegalArgumentException - if array is null
      IllegalArgumentException - if any element in the array is null

    • getInstance

      public static Closure getInstance(Map 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.

      Parameters:
      predicatesAndClosures - a map of predicates to closures
      Returns:
      the switch closure
      Throws:
      IllegalArgumentException - if the map is null
      IllegalArgumentException - if any closure in the map is null
      ClassCastException - if the map elements are of the wrong type

    • execute

      public void execute(Object input)
      Executes the closure whose matching predicate returns true
      Specified by:
      execute in interface Closure
      Parameters:
      input - the input object

    • getPredicates

      public Predicate[] getPredicates()
      Gets the predicates, do not modify the array.
      Returns:
      the predicates
      Since:
      Commons Collections 3.1

    • getClosures

      public Closure[] getClosures()
      Gets the closures, do not modify the array.
      Returns:
      the closures
      Since:
      Commons Collections 3.1

    • getDefaultClosure

      public Closure getDefaultClosure()
      Gets the default closure.
      Returns:
      the default closure
      Since:
      Commons Collections 3.1