de.gerdiproject.harvest.utils

Class CollectionUtils

java.lang.Object

de.gerdiproject.harvest.utils.CollectionUtils

public class CollectionUtils
extends Object

This class contains static methods for manipulating Collections and related classes.

Author:

Robin Weiss

Method Summary

Modifier and Type	Method and Description
static <T> List<T>	addToList(List<T> list, Collection<T> addedElements) Static helper that adds elements to an existing List, or creates a new LinkedList if nothing was added before.
static <T> Map<String,T>	addToMap(Map<String,T> map, String key, T value) Static helper that puts a value to an existing Map, or creates a new HashMap if nothing was added before.
static <T> Set<T>	addToSet(Set<T> set, Collection<T> addedElements) Static helper that adds elements to an existing Set, or creates a new HashSet if nothing was added before.

Methods inherited from class java.lang.Object

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

Method Detail

addToSet

public static <T> Set<T> addToSet(Set<T> set,
                                  Collection<T> addedElements)

Static helper that adds elements to an existing Set, or creates a new HashSet if nothing was added before. Also removes null elements and cleans the items prior to adding them, if they implement ICleanable.

Type Parameters:

T - the type of the set and added elements

Parameters:

set - the set to which the elements are added, or null if no set exists yet

addedElements - the elements that are to be added

Returns:

a set with the added elements, or null if the set is empty after the operation

addToList

public static <T> List<T> addToList(List<T> list,
                                    Collection<T> addedElements)

Static helper that adds elements to an existing List, or creates a new LinkedList if nothing was added before. Also removes null- and duplicate elements and cleans the items prior to adding them, if they implement ICleanable. Elements that cannot be cleaned are not added to the list

Type Parameters:

T - the type of the list and added elements

Parameters:

list - the list to which the elements are added, or null if no list exists yet

addedElements - the elements that are to be added

Returns:

a list with the added elements, or null if the list is empty after the operation

addToMap

public static <T> Map<String,T> addToMap(Map<String,T> map,
                                         String key,
                                         T value)

Static helper that puts a value to an existing Map, or creates a new HashMap if nothing was added before. Also removes cleans the value prior to adding it, if it implements ICleanable. Values that cannot be cleaned are not put into the map.

Type Parameters:

T - the type of the added value

Parameters:

map - the map to which the value is added, or null if no map exists yet

key - the key at which the value is stored in the map

value - the value that is to be put into the map

Returns:

a map with the added value, or null if the map is empty after the operation