org.javarosa.xform.parse

Class RandomizeHelper

java.lang.Object

org.javarosa.xform.parse.RandomizeHelper

public final class RandomizeHelper
extends Object

This class contains all the code needed to implement the xform randomize() function.

Constructor Summary

Constructors

Constructor and Description
RandomizeHelper()

Method Summary

Modifier and Type	Method and Description
static <T> List<T>	shuffle(List<T> elements) This method will return a new list with the same elements, randomly reordered.
static <T> List<T>	shuffle(List<T> elements, Long seed) This method will return a new list with the same elements, randomly reordered.

Methods inherited from class java.lang.Object

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

Constructor Detail

RandomizeHelper

public RandomizeHelper()

Method Detail

shuffle

public static <T> List<T> shuffle(List<T> elements)

This method will return a new list with the same elements, randomly reordered. Every call to this method will produce a different random seed, which will potentially produce a different ordering each time.

Type Parameters:

T - Type of the elements in the list

Parameters:

elements - List of elements of type T to be shuffled

Returns:

a new List with the same input elements reordered

shuffle

public static <T> List<T> shuffle(List<T> elements,
                                  Long seed)

This method will return a new list with the same elements, randomly reordered. Given the same seed, calls to this method will produce exactly the same output.

Type Parameters:

T - Type of the elements in the list

Parameters:

elements - List of elements of type T to be shuffled

seed - Long seed for the Random number generator

Returns:

a new List with the same input elements reordered