Package org.openxava.util

Class XCollections

java.lang.Object

org.openxava.util.XCollections

public class XCollections
extends Object

Utilities to work with collections, enumerations and iterators.

Author:

Javier Paniza

Constructor Summary

Constructors

Constructor	Description
XCollections()

Method Summary

Modifier and Type	Method	Description
static void	add(Collection collection, Enumeration toAdd)	Adds elements from the enumeration to the collection.
static boolean	isEmptyOrZero(Collection values)	It's empty if is null, without elements, with null elements or elements with neutral value (empty strings, collections, nulls or zeroes).
static Object	last(Collection collection)	Returns the last element of sent collection.
static void	move(List list, int from, int to)
static void	println(Collection c)	Print in standard output the collection elements.
static void	println(Iterator it)	Print in standard output the elements by it iterate.
static Collection	toCollection(Enumeration e)	Returns a collection from a enumeration.
static List	toList(Iterable it)	Returns a List from an Iterable.
static String[]	toStringArray(Collection c)	Returns a String [] from a collection of Strings.

Methods inherited from class java.lang.Object

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

Constructor Details

XCollections

public XCollections()

Method Details

last

public static Object last(Collection collection)

Returns the last element of sent collection.

Parameters:

collection - Can be null

Returns:

Last element, or null if collection is null or empty.

add

public static void add(Collection collection,
 Enumeration toAdd)

Adds elements from the enumeration to the collection.

Parameters:

collection - Not null

toAdd - If null no elements are added.

println

public static void println(Collection c)

Print in standard output the collection elements.

Util to debug.

Parameters:

c - Can be null.

println

public static void println(Iterator it)

Print in standard output the elements by it iterate.

Util to debug.

Parameters:

c - Can be null.

toCollection

public static Collection toCollection(Enumeration e)

Returns a collection from a enumeration.

Parameters:

e - If null then returns a empty collection.

Returns:

Not null.

toList

public static List toList(Iterable it)

Returns a List from an Iterable.

Parameters:

it - If null then returns a empty list.

Returns:

Not null.

Since:

5.6.1

toStringArray

public static String[] toStringArray(Collection c)

Returns a String [] from a collection of Strings.

Parameters:

c - Elements must be of type String. If null then returns a empty array.

Returns:

Not null.

move

public static void move(List list,
 int from,
 int to)

Since:

5.2

isEmptyOrZero

public static boolean isEmptyOrZero(Collection values)

It's empty if is null, without elements, with null elements or elements with neutral value (empty strings, collections, nulls or zeroes). Mirrors Maps.isEmptyOrZero(Map) semantics for collections. Numeric values with value 0 are considered empty.

Parameters:

values - Can be null.

Since:

7.6