uk.ac.ed.inf.utils
Class ListUtils

java.lang.Object
  uk.ac.ed.inf.utils.ListUtils

public class ListUtils
extends java.lang.Object

Utilities to manipulate lists

Version:

4 Jan 2008

Author:

Luna De Ferrari luna.deferrari-at-ed.ac.uk

Constructor Summary

ListUtils()

Method Summary

static java.lang.String[]	addStringToArray(java.lang.String[] array, java.lang.String textToAdd) Takes an array and adds a string to all elements
static java.util.ArrayList<java.lang.String>	addStringToArrayList(java.util.ArrayList list, java.lang.String textToAdd) Takes an arrayList and adds a string to all elements
static java.util.Set<java.lang.String>	cleanSet(java.util.Set<java.lang.String> set) Cleans a set from null and empty elements
static java.util.LinkedHashSet	getCommonElements(java.util.ArrayList list1, java.util.ArrayList list2) Gets the elements present in both lists
static int	getLongestStringLength(java.util.ArrayList<java.lang.String> array) Get the length of the longest string in an array
static int	getShortestStringLength(java.util.ArrayList<java.lang.String> array) Get the length of the shortest string in an array
static boolean	isNullOrEmpty(java.lang.String string) tells if a string is null or empty
static boolean	isNullOrEmpty(java.util.Vector<java.lang.String> list) tells if a list is null or empty
static void	printList(java.util.List list) Prints an array as a list of 'index' + 'array element' (with a header containing the size)
static void	printListsOfLists(java.util.List<java.util.List> list) Prints lists of lists
static java.util.TreeSet<java.lang.String>	setFromList(java.util.ArrayList<java.lang.String> list) create a set (elements appear only once) from a list
static java.util.Vector<java.lang.String>	vectorFromList(java.util.ArrayList<java.lang.String> list)

Methods inherited from class java.lang.Object

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

Constructor Detail

ListUtils

public ListUtils()

Method Detail

addStringToArray

public static java.lang.String[] addStringToArray(java.lang.String[] array,
                                                  java.lang.String textToAdd)

Takes an array and adds a string to all elements

addStringToArrayList

public static java.util.ArrayList<java.lang.String> addStringToArrayList(java.util.ArrayList list,
                                                                         java.lang.String textToAdd)

Takes an arrayList and adds a string to all elements

cleanSet

public static java.util.Set<java.lang.String> cleanSet(java.util.Set<java.lang.String> set)

Cleans a set from null and empty elements

Parameters:

set -

Returns:

a set without the null element or the empty string

getCommonElements

public static java.util.LinkedHashSet getCommonElements(java.util.ArrayList list1,
                                                        java.util.ArrayList list2)

Gets the elements present in both lists

Parameters:

list1 - a list

list2 - another list

Returns:

the set containing the common elements (each element only once)

getLongestStringLength

public static int getLongestStringLength(java.util.ArrayList<java.lang.String> array)

Get the length of the longest string in an array

Parameters:

array - an array of strings

Returns:

the length of the longest string

getShortestStringLength

public static int getShortestStringLength(java.util.ArrayList<java.lang.String> array)

Get the length of the shortest string in an array

Parameters:

array - an array of strings

Returns:

the length of the shortest string

isNullOrEmpty

public static boolean isNullOrEmpty(java.lang.String string)

tells if a string is null or empty

Parameters:

string - a string

Returns:

true if the string is null or empty (no characters), false otherwise

isNullOrEmpty

public static boolean isNullOrEmpty(java.util.Vector<java.lang.String> list)

tells if a list is null or empty

Parameters:

list -

Returns:

true if the list is null or empty, false otherwise

printList

public static void printList(java.util.List list)

Prints an array as a list of 'index' + 'array element' (with a header containing the size)

Parameters:

list - the List to print

printListsOfLists

public static void printListsOfLists(java.util.List<java.util.List> list)

Prints lists of lists

Parameters:

list -

setFromList

public static java.util.TreeSet<java.lang.String> setFromList(java.util.ArrayList<java.lang.String> list)

create a set (elements appear only once) from a list

vectorFromList

public static java.util.Vector<java.lang.String> vectorFromList(java.util.ArrayList<java.lang.String> list)