CollectionUtils (XDEV Application Framework 6.0.0 API)

java.lang.Object
- xdev.util.CollectionUtils

```
public final class CollectionUtils
extends Object
```
The CollectionUtils class provides utility methods for Collection handling.

Since:

2.0

Author:

XDEV Software

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static <K,V> void`	`accumulate(Map<K,List<V>> map, K key, V value)` Adds `value` to the list associated with `key` in `map`. If `key` has no value yet, a list is created fist.
`static <E> void`	`addAll(Collection<? super E> collection, E... elements)` Appends the specified `elements` to the `collection`.
`static int`	`addIfNotInList(List<?> list, List<?> elements)` Appends the specified `elements` to the list if the `elements` are not already present in the list.
`static <E> boolean`	`addIfNotInList(List<E> list, E element, Comparer<E> comparer)` Appends the specified `element` to the list if the `element` is not already present in the list.
`static <E> int`	`addIfNotInList(List<E> list, List<E> elements, Comparer<E> comparer)` Appends the specified `elements` to the list if the `elements` are not already present in the list. The `comparer` is used to compare the elements.
`static boolean`	`addIfNotInList(List list, Object element)` Appends the specified `element` to the list if the `element` is not already present in the list.
`static <T> Enumeration<T>`	`asEnumeration(Iterator<T> e)` Returns an enumeration over the specified iterator.
`static <T> Iterator<T>`	`asIterator(Enumeration<T> e)` Returns an iterator over the specified enumeration.
`static <T> Set<T>`	`asLinkedSet(T... values)` Returns a set containing all of the elements in this `values`.
`static <T> List<T>`	`asList(Enumeration<T> e)` Returns an list containing all of the elements in this `e` in proper sequence (from first to last element).
`static <T> List<T>`	`asList(Iterator<T> it)` Returns an list containing all of the elements in this `it` in proper sequence (from first to last element).
`static <T> List<T>`	`asList(T... values)` Returns an list containing all of the elements in this `values` in proper sequence (from first to last element).
`static <T> Set<T>`	`asSet(T... values)` Returns a set containing all of the elements in this `values`. It makes no guarantees as to the iteration order of the set; in particular, it does not guarantee that the order will remain constant over time.
`static <E> boolean`	`contains(List<E> list, E element, Comparer<E> comparer)` Returns `true` if the `list` contains the specified element.
`static void`	`copyIntoArray(Collection c, int collectionOffset, Object[] array, int destOffset, int count)` Copies an collection from the specified `c`, beginning at the specified position, to the specified position of the destination array.
`static void`	`copyIntoArray(Collection c, Object[] array, int destOffset)` Copies collection elements into the given `array`.
`static <E> List<E>`	`createList(E value, int count)` Create a `List` with the size of `count`.
`static void`	`deleteDoubleValues(List list)` Delete all double values of the `list`.
`static void`	`ensureCapacity(List<?> list, int add)` Increases the capacity of this `List` instance by `add` .
`static int`	`frequency(Collection<?> c, Object search)` Returns the number of elements in the specified collection equal to the specified object.
`static boolean`	`hasDoubleValues(List list)` Returns `true` if the `list` has double elements.
`static <E> int`	`indexOf(List<E> list, E element, Comparer<E> comparer)` Returns the index of the first occurrence of the specified element in the `list`, or -1 if this list does not contain the element.
`static int`	`indexOf(List list, Object element, int... skipIndices)`
`static <T> int[]`	`indicesOf(List<T> list, T... obj)` Returns the indices of the occurrence of the specified elements in the `list`.
`static void`	`move(List list, int index, boolean up)` Move the element at the specified positions (`index`).
`static void`	`move(List list, int from, int to)` Move the element at the specified positions (`from`) to the specified position (`to`) in the `list`.
`static void`	`move(List list, int firstIndex, int lastIndex, int to)`
`static int`	`remove(Map map, Object value)` Removes the specified `value` from the `map`, if they are present (optional operation).
`static <E> int`	`removeAll(Collection<? super E> list, E... elements)` Removes the specified `elements` from the `list`, if they are present (optional operation).
`static <E extends Enum<E>> void`	`sortByName(List<E> list)`
`static void`	`swap(List list, int index1, int index2)` Swaps the elements at the specified positions in the specified list.
`static Map<String,Object>`	`toMap(ResourceBundle bundle)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - copyIntoArray
```
public static void copyIntoArray(Collection c,
                                 Object[] array,
                                 int destOffset)
                          throws IndexOutOfBoundsException,
                                 ArrayStoreException,
                                 NullPointerException
```
    Copies collection elements into the given array.
    This method is a alias for CollectionUtils.copyIntoArray(c,0,array,destOffset,c.size());
    
    Parameters:
    
    c - the collection to copy
    
    array - the destination array
    
    destOffset - starting position in the array
    
    Throws:
    
    IndexOutOfBoundsException - if copying would cause access of data outside array bounds.
    
    ArrayStoreException - if an element in the c could not be stored into the array because of a type mismatch.
    
    NullPointerException - if either c or array is null.
    
    See Also:
    
    copyIntoArray(Collection, int, Object[], int, int)
  - copyIntoArray
```
public static void copyIntoArray(Collection c,
                                 int collectionOffset,
                                 Object[] array,
                                 int destOffset,
                                 int count)
                          throws IndexOutOfBoundsException,
                                 ArrayStoreException,
                                 NullPointerException
```
    Copies an collection from the specified c, beginning at the specified position, to the specified position of the destination array.
    
    Parameters:
    
    c - the collection to copy
    
    collectionOffset - starting position in the source collection
    
    array - the destination array
    
    destOffset - starting position in the array
    
    count - the number of elements to be copied
    
    Throws:
    
    IndexOutOfBoundsException - if copying would cause access of data outside array bounds.
    
    ArrayStoreException - if an element in the c could not be stored into the array because of a type mismatch.
    
    NullPointerException - if either c or array is null.
    
    See Also:
    
    System.arraycopy(Object, int, Object, int, int)
  - asList
```
public static <T> List<T> asList(T... values)
```
    Returns an list containing all of the elements in this values in proper sequence (from first to last element).
    The runtime type of the returned List is that of the specified T.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    values - an array of type T elements
    
    Returns:
    
    a list containing the elements of this values
    
    See Also:
    
    Arrays.asList(Object...)
  - asList
```
public static <T> List<T> asList(Enumeration<T> e)
```
    Returns an list containing all of the elements in this e in proper sequence (from first to last element).
    The runtime type of the returned List is that of the specified T.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    e - an Enumeration of type T
    
    Returns:
    
    a list containing the elements of this e
  - asList
```
public static <T> List<T> asList(Iterator<T> it)
```
    Returns an list containing all of the elements in this it in proper sequence (from first to last element).
    The runtime type of the returned List is that of the specified T.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    it - an Iterator of type T
    
    Returns:
    
    a list containing the elements of this it
  - asIterator
```
public static <T> Iterator<T> asIterator(Enumeration<T> e)
```
    Returns an iterator over the specified enumeration.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    e - an Enumeration of type T
    
    Returns:
    
    an Iterator over the specified enumeration
  - asEnumeration
```
public static <T> Enumeration<T> asEnumeration(Iterator<T> e)
```
    Returns an enumeration over the specified iterator.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    e - an Iterator of type T
    
    Returns:
    
    an Enumeration over the specified iterator
  - createList
```
public static <E> List<E> createList(E value,
                                     int count)
```
    Create a List with the size of count. The value are added count times.
    The runtime type of the returned List is that of the specified E.
    
    Type Parameters:
    
    E - any type
    
    Parameters:
    
    value - the element to insert into the list
    
    count - the number of E elements of the list
    
    Returns:
    
    a list containing the value
  - asSet
```
public static <T> Set<T> asSet(T... values)
```
    Returns a set containing all of the elements in this values.
    It makes no guarantees as to the iteration order of the set; in particular, it does not guarantee that the order will remain constant over time.
    The runtime type of the returned Set is that of the specified T.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    values - an array of type T elements
    
    Returns:
    
    a Set containing the elements of this values
    
    See Also:
    
    Set, HashSet
  - asLinkedSet
```
public static <T> Set<T> asLinkedSet(T... values)
```
    Returns a set containing all of the elements in this values. with predictable iteration order
    The runtime type of the returned Set is that of the specified T.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    values - an array of type T elements
    
    Returns:
    
    a Set containing the elements of this values
    
    See Also:
    
    Set
  - addAll
```
public static <E> void addAll(Collection<? super E> collection,
                              E... elements)
```
    Appends the specified elements to the collection. The capacity of the collection is increased by the count of the elements.
    
    Parameters:
    
    collection - the destination Collection
    
    elements - the elements to be placed in the collection
  - removeAll
```
public static <E> int removeAll(Collection<? super E> list,
                                E... elements)
```
    Removes the specified elements from the list, if they are present (optional operation).
    
    Parameters:
    
    list - the destination Collection
    
    elements - the elements to be removed from the list
    
    Returns:
    
    the count of the removed elements
    
    See Also:
    
    Collection.removeAll(Collection)
  - remove
```
public static int remove(Map map,
                         Object value)
```
    Removes the specified value from the map, if they are present (optional operation).
    
    Parameters:
    
    map - the destination Map
    
    value - the element to be removed from the map
    
    Returns:
    
    the count of the removed elements
    
    See Also:
    
    Object.equals(Object), Iterator
  - ensureCapacity
```
public static void ensureCapacity(List<?> list,
                                  int add)
```
    Increases the capacity of this List instance by add .
    
    Parameters:
    
    list - the List to increase the size
    
    add - the additional capacity
  - addIfNotInList
```
public static int addIfNotInList(List<?> list,
                                 List<?> elements)
```
    Appends the specified elements to the list if the elements are not already present in the list.
    
    Parameters:
    
    list - the destination List
    
    elements - the list of elements to add
    
    Returns:
    
    the number of added elements
  - addIfNotInList
```
public static <E> int addIfNotInList(List<E> list,
                                     List<E> elements,
                                     Comparer<E> comparer)
```
    Appends the specified elements to the list if the elements are not already present in the list.
    The comparer is used to compare the elements.
    
    Type Parameters:
    
    E - any type
    
    Parameters:
    
    list - the destination List
    
    elements - the list of elements to add
    
    comparer - the comparer by which the element are compared.
    
    Returns:
    
    the number of added elements as int
  - addIfNotInList
```
public static boolean addIfNotInList(List list,
                                     Object element)
```
    Appends the specified element to the list if the element is not already present in the list.
    
    Parameters:
    
    list - the destination List
    
    element - a Object to add
    
    Returns:
    
    true if the element is added, otherwise flase
  - addIfNotInList
```
public static <E> boolean addIfNotInList(List<E> list,
                                         E element,
                                         Comparer<E> comparer)
```
    Appends the specified element to the list if the element is not already present in the list.
    
    Type Parameters:
    
    E - any type
    
    Parameters:
    
    list - the destination List
    
    element - the element to be searched for.
    
    comparer - the comparer by which the element are compared.
    
    Returns:
    
    true if the element is added, false if the element is already present in the list
  - contains
```
public static <E> boolean contains(List<E> list,
                                   E element,
                                   Comparer<E> comparer)
                            throws NullPointerException
```
    Returns true if the list contains the specified element. The comparer is used to compare the elements.
    
    Type Parameters:
    
    E - any type
    
    Parameters:
    
    list - the destination List
    
    element - the element to be searched for.
    
    comparer - the comparer by which the element are compared.
    
    Returns:
    
    true if the list contains the element, otherwise false
    
    Throws:
    
    NullPointerException - if the comparer is null
    
    See Also:
    
    indexOf(List, Object, Comparer)
  - indexOf
```
public static <E> int indexOf(List<E> list,
                              E element,
                              Comparer<E> comparer)
                       throws NullPointerException
```
    Returns the index of the first occurrence of the specified element in the list, or -1 if this list does not contain the element.
    
    Type Parameters:
    
    E - any type
    
    Parameters:
    
    list - the list to be searched.
    
    element - the element to be searched for.
    
    comparer - the comparer by which the element are compared.
    
    Returns:
    
    the index of the search element, if it is contained in the list otherwise -1.
    
    Throws:
    
    NullPointerException - if the list or comparer is null
  - deleteDoubleValues
```
public static void deleteDoubleValues(List list)
```
    Delete all double values of the list.
    
    Parameters:
    
    list - the destination list
    
    See Also:
    
    hasDoubleValues(List)
  - hasDoubleValues
```
public static boolean hasDoubleValues(List list)
```
    Returns true if the list has double elements.
    
    Parameters:
    
    list - the destination List
    
    Returns:
    
    true if the list has double elements, otherwise false
  - indexOf
```
public static int indexOf(List list,
                          Object element,
                          int... skipIndices)
```
  - indicesOf
```
public static <T> int[] indicesOf(List<T> list,
                                  T... obj)
                           throws NullPointerException
```
    Returns the indices of the occurrence of the specified elements in the list.
    
    Type Parameters:
    
    T - any type
    
    Parameters:
    
    list - the destination List
    
    obj - the elements to searched for
    
    Returns:
    
    the indices of the search elements as int array
    
    Throws:
    
    NullPointerException - if list is null
  - frequency
```
public static int frequency(Collection<?> c,
                            Object search)
                     throws NullPointerException
```
    Returns the number of elements in the specified collection equal to the specified object.
    
    Parameters:
    
    c - the collection in which to determine the frequency of search
    
    search - the object whose frequency is to be determined
    
    Returns:
    
    the number of elements in c equal to the specified object.
    
    Throws:
    
    NullPointerException - if c is null
  - swap
```
public static void swap(List list,
                        int index1,
                        int index2)
                 throws IndexOutOfBoundsException
```
    Swaps the elements at the specified positions in the specified list.
    
    Parameters:
    
    list - The list in which to swap elements
    
    index1 - the index of one element to be swapped
    
    index2 - the index of the other element to be swapped
    
    Throws:
    
    IndexOutOfBoundsException - if either index1 or index2 is out of range (index1 < 0 || index1 >= list.size() || index2 < 0 || index2 >= list.size()).
  - move
```
public static void move(List list,
                        int index,
                        boolean up)
```
    Move the element at the specified positions (index).
    
    Parameters:
    
    list - The list in which to move elements
    
    index - the index of the element to be moved
    
    up - define the elements new position; if true the new index is increased by 1, otherwise the the new index is reduced by 1
  - move
```
public static void move(List list,
                        int from,
                        int to)
```
    Move the element at the specified positions (from) to the specified position (to) in the list.
    
    Parameters:
    
    list - The list in which to move elements
    
    from - the index of the element to be moved
    
    to - the index of the elements new position
  - move
```
public static void move(List list,
                        int firstIndex,
                        int lastIndex,
                        int to)
                 throws IndexOutOfBoundsException
```
    Throws:
    
    IndexOutOfBoundsException
  - sortByName
```
public static <E extends Enum<E>> void sortByName(List<E> list)
```
  - accumulate
```
public static <K,V> void accumulate(Map<K,List<V>> map,
                                    K key,
                                    V value)
```
    Adds value to the list associated with key in map.
    If key has no value yet, a list is created fist.
    
    Type Parameters:
    
    K - The key's type
    
    V - The value's type
    
    Parameters:
    
    map - The store
    
    key - The key associated with value
    
    value - The value to accumulate
  - toMap
```
public static Map<String,Object> toMap(ResourceBundle bundle)
```

Class CollectionUtils

Method Summary

Methods inherited from class java.lang.Object

Method Detail

copyIntoArray

copyIntoArray

asList

asList

asList

asIterator

asEnumeration

createList

asSet

asLinkedSet

addAll

removeAll

remove

ensureCapacity

addIfNotInList

addIfNotInList

addIfNotInList

addIfNotInList

contains

indexOf

deleteDoubleValues

hasDoubleValues

indexOf

indicesOf

frequency

swap

move

move

move

sortByName

accumulate

toMap