javafx.collections

Class FXCollections

java.lang.Object

javafx.collections.FXCollections

public class FXCollections
extends Object

Utility class that consists of static methods that are 1:1 copies of java.util.Collections methods.

The wrapper methods (like synchronizedObservableList or emptyObservableList) has exactly the same functionality as the methods in Collections, with exception that they return ObservableList and are therefore suitable for methods that require ObservableList on input.

The utility methods are here mainly for performance reasons. All methods are optimized in a way that they yield only limited number of notifications. On the other hand, java.util.Collections methods might call "modification methods" on an ObservableList multiple times, resulting in a number of notifications.

Since:

JavaFX 2.0

Method Summary

All MethodsStatic MethodsConcrete Methods
Modifier and Type	Method and Description
`static <E> ObservableList<E>`	`checkedObservableList(ObservableList<E> list, Class<E> type)` Creates and returns a typesafe wrapper on top of provided observable list.
`static <K,V> ObservableMap<K,V>`	`checkedObservableMap(ObservableMap<K,V> map, Class<K> keyType, Class<V> valueType)` Creates and returns a typesafe wrapper on top of provided observable map.
`static <E> ObservableSet<E>`	`checkedObservableSet(ObservableSet<E> set, Class<E> type)` Creates and returns a typesafe wrapper on top of provided observable set.
`static <E> ObservableList<E>`	`concat(ObservableList<E>... lists)` Concatenates more observable lists into one.
`static <T> void`	`copy(ObservableList<? super T> dest, List<? extends T> src)` Copies elements from src to dest.
`static <E> ObservableList<E>`	`emptyObservableList()` Creates and empty unmodifiable observable list.
`static <K,V> ObservableMap<K,V>`	`emptyObservableMap()` Creates and empty unmodifiable observable map.
`static <E> ObservableSet<E>`	`emptyObservableSet()` Creates and empty unmodifiable observable set.
`static <T> void`	`fill(ObservableList<? super T> list, T obj)` Fills the provided list with obj.
`static <E> ObservableList<E>`	`observableArrayList()` Creates a new empty observable list that is backed by an arraylist.
`static <E> ObservableList<E>`	`observableArrayList(Callback<E,Observable[]> extractor)` Creates a new empty observable list backed by an arraylist.
`static <E> ObservableList<E>`	`observableArrayList(Collection<? extends E> col)` Creates a new observable array list and adds a content of collection `col` to it.
`static <E> ObservableList<E>`	`observableArrayList(E... items)` Creates a new observable array list with `items` added to it.
`static ObservableFloatArray`	`observableFloatArray()` Creates a new empty observable float array.
`static ObservableFloatArray`	`observableFloatArray(float... values)` Creates a new observable float array with `values` set to it.
`static ObservableFloatArray`	`observableFloatArray(ObservableFloatArray array)` Creates a new observable float array with copy of elements in given `array`.
`static <K,V> ObservableMap<K,V>`	`observableHashMap()` Creates a new empty observable map that is backed by a HashMap.
`static ObservableIntegerArray`	`observableIntegerArray()` Creates a new empty observable integer array.
`static ObservableIntegerArray`	`observableIntegerArray(int... values)` Creates a new observable integer array with `values` set to it.
`static ObservableIntegerArray`	`observableIntegerArray(ObservableIntegerArray array)` Creates a new observable integer array with copy of elements in given `array`.
`static <E> ObservableList<E>`	`observableList(List<E> list)` Constructs an ObservableList that is backed by the specified list.
`static <E> ObservableList<E>`	`observableList(List<E> list, Callback<E,Observable[]> extractor)` Constructs an ObservableList that is backed by the specified list.
`static <K,V> ObservableMap<K,V>`	`observableMap(Map<K,V> map)` Constructs an ObservableMap that is backed by the specified map.
`static <E> ObservableSet<E>`	`observableSet(E... elements)` Constructs an ObservableSet backed by a HashSet that contains all the specified elements.
`static <E> ObservableSet<E>`	`observableSet(Set<E> set)` Constructs an ObservableSet that is backed by the specified set.
`static <T> boolean`	`replaceAll(ObservableList<T> list, T oldVal, T newVal)` Replace all oldVal elements in the list with newVal element.
`static void`	`reverse(ObservableList list)` Reverse the order in the list Fires only one change notification on the list.
`static void`	`rotate(ObservableList list, int distance)` Rotates the list by distance.
`static void`	`shuffle(ObservableList<?> list)` Shuffles all elements in the observable list.
`static void`	`shuffle(ObservableList list, Random rnd)` Shuffles all elements in the observable list.
`static <E> ObservableList<E>`	`singletonObservableList(E e)` Creates an unmodifiable observable list with single element.
`static <T extends Comparable<? super T>> void`	`sort(ObservableList<T> list)` Sorts the provided observable list.
`static <T> void`	`sort(ObservableList<T> list, Comparator<? super T> c)` Sorts the provided observable list using the c comparator.
`static <E> ObservableList<E>`	`synchronizedObservableList(ObservableList<E> list)` Creates and returns a synchronized wrapper on top of provided observable list.
`static <K,V> ObservableMap<K,V>`	`synchronizedObservableMap(ObservableMap<K,V> map)` Creates and returns a synchronized wrapper on top of provided observable map.
`static <E> ObservableSet<E>`	`synchronizedObservableSet(ObservableSet<E> set)` Creates and returns a synchronized wrapper on top of provided observable set.
`static <E> ObservableList<E>`	`unmodifiableObservableList(ObservableList<E> list)` Creates and returns unmodifiable wrapper list on top of provided observable list.
`static <K,V> ObservableMap<K,V>`	`unmodifiableObservableMap(ObservableMap<K,V> map)` Constructs a read-only interface to the specified ObservableMap.
`static <E> ObservableSet<E>`	`unmodifiableObservableSet(ObservableSet<E> set)` Creates and returns unmodifiable wrapper on top of provided observable set.

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

Method Detail
- observableList
```
public static <E> ObservableList<E> observableList(List<E> list)
```
  Constructs an ObservableList that is backed by the specified list. Mutation operations on the ObservableList instance will be reported to observers that have registered on that instance.
  Note that mutation operations made directly to the underlying list are not reported to observers of any ObservableList that wraps it.
  
  Parameters:
  
  list - a concrete List that backs this ObservableList
  
  Returns:
  
  a newly created ObservableList
- observableList
```
public static <E> ObservableList<E> observableList(List<E> list,
                                                   Callback<E,Observable[]> extractor)
```
  Constructs an ObservableList that is backed by the specified list. Mutation operations on the ObservableList instance will be reported to observers that have registered on that instance.
  Note that mutation operations made directly to the underlying list are not reported to observers of any ObservableList that wraps it.
  This list also reports mutations of the elements in it by using extractor. Observable objects returned by extractor (applied to each list element) are listened for changes and transformed into "update" change of ListChangeListener.
  
  Parameters:
  
  list - a concrete List that backs this ObservableList
  
  Returns:
  
  a newly created ObservableList
  
  Since:
  
  JavaFX 2.1
- observableMap
```
public static <K,V> ObservableMap<K,V> observableMap(Map<K,V> map)
```
  Constructs an ObservableMap that is backed by the specified map. Mutation operations on the ObservableMap instance will be reported to observers that have registered on that instance.
  Note that mutation operations made directly to the underlying map are not reported to observers of any ObservableMap that wraps it.
  
  Parameters:
  
  map - a Map that backs this ObservableMap
  
  Returns:
  
  a newly created ObservableMap
- observableSet
```
public static <E> ObservableSet<E> observableSet(Set<E> set)
```
  Constructs an ObservableSet that is backed by the specified set. Mutation operations on the ObservableSet instance will be reported to observers that have registered on that instance.
  Note that mutation operations made directly to the underlying set are not reported to observers of any ObservableSet that wraps it.
  
  Parameters:
  
  set - a Set that backs this ObservableSet
  
  Returns:
  
  a newly created ObservableSet
  
  Since:
  
  JavaFX 2.1
- observableSet
```
public static <E> ObservableSet<E> observableSet(E... elements)
```
  Constructs an ObservableSet backed by a HashSet that contains all the specified elements.
  
  Parameters:
  
  elements - elements that will be added into returned ObservableSet
  
  Returns:
  
  a newly created ObservableSet
  
  Since:
  
  JavaFX 2.1
- unmodifiableObservableMap
```
public static <K,V> ObservableMap<K,V> unmodifiableObservableMap(ObservableMap<K,V> map)
```
  Constructs a read-only interface to the specified ObservableMap. Only mutation operations made to the underlying ObservableMap will be reported to observers that have registered on the unmodifiable instance. This allows clients to track changes in a Map but disallows the ability to modify it.
  
  Parameters:
  
  map - an ObservableMap that is to be monitored by this interface
  
  Returns:
  
  a newly created UnmodifiableObservableMap
- checkedObservableMap
```
public static <K,V> ObservableMap<K,V> checkedObservableMap(ObservableMap<K,V> map,
                                                            Class<K> keyType,
                                                            Class<V> valueType)
```
  Creates and returns a typesafe wrapper on top of provided observable map.
  
  Parameters:
  
  map - an Observable map to be wrapped
  
  Returns:
  
  a dynamically typesafe view of the specified map
  
  Since:
  
  JavaFX 8.0
  
  See Also:
  
  Collections#checkedMap(java.util.Map, java.lang.Class)
- synchronizedObservableMap
```
public static <K,V> ObservableMap<K,V> synchronizedObservableMap(ObservableMap<K,V> map)
```
  Creates and returns a synchronized wrapper on top of provided observable map.
  
  Parameters:
  
  map - the map to be "wrapped" in a synchronized map.
  
  Returns:
  
  A synchronized version of the observable map
  
  Since:
  
  JavaFX 8.0
  
  See Also:
  
  Collections.synchronizedMap(java.util.Map)
- emptyObservableMap
```
public static <K,V> ObservableMap<K,V> emptyObservableMap()
```
  Creates and empty unmodifiable observable map.
  
  Returns:
  
  An empty unmodifiable observable map
  
  Since:
  
  JavaFX 8.0
  
  See Also:
  
  Collections.emptyMap()
- observableIntegerArray
```
public static ObservableIntegerArray observableIntegerArray()
```
  Creates a new empty observable integer array.
  
  Returns:
  
  a newly created ObservableIntegerArray
  
  Since:
  
  JavaFX 8.0
- observableIntegerArray
```
public static ObservableIntegerArray observableIntegerArray(int... values)
```
  Creates a new observable integer array with values set to it.
  
  Parameters:
  
  values - the values that will be in the new observable integer array
  
  Returns:
  
  a newly created ObservableIntegerArray
  
  Since:
  
  JavaFX 8.0
- observableIntegerArray
```
public static ObservableIntegerArray observableIntegerArray(ObservableIntegerArray array)
```
  Creates a new observable integer array with copy of elements in given array.
  
  Parameters:
  
  array - observable integer array to copy
  
  Returns:
  
  a newly created ObservableIntegerArray
  
  Since:
  
  JavaFX 8.0
- observableFloatArray
```
public static ObservableFloatArray observableFloatArray()
```
  Creates a new empty observable float array.
  
  Returns:
  
  a newly created ObservableFloatArray
  
  Since:
  
  JavaFX 8.0
- observableFloatArray
```
public static ObservableFloatArray observableFloatArray(float... values)
```
  Creates a new observable float array with values set to it.
  
  Parameters:
  
  values - the values that will be in the new observable float array
  
  Returns:
  
  a newly created ObservableFloatArray
  
  Since:
  
  JavaFX 8.0
- observableFloatArray
```
public static ObservableFloatArray observableFloatArray(ObservableFloatArray array)
```
  Creates a new observable float array with copy of elements in given array.
  
  Parameters:
  
  array - observable float array to copy
  
  Returns:
  
  a newly created ObservableFloatArray
  
  Since:
  
  JavaFX 8.0
- observableArrayList
```
public static <E> ObservableList<E> observableArrayList()
```
  Creates a new empty observable list that is backed by an arraylist.
  
  Returns:
  
  a newly created ObservableList
  
  See Also:
  
  observableList(java.util.List)
- observableArrayList
```
public static <E> ObservableList<E> observableArrayList(Callback<E,Observable[]> extractor)
```
  Creates a new empty observable list backed by an arraylist. This list reports element updates.
  
  Parameters:
  
  extractor - element to Observable[] convertor. Observable objects are listened for changes on the element.
  
  Returns:
  
  a newly created ObservableList
  
  Since:
  
  JavaFX 2.1
  
  See Also:
  
  observableList(java.util.List, javafx.util.Callback)
- observableArrayList
```
public static <E> ObservableList<E> observableArrayList(E... items)
```
  Creates a new observable array list with items added to it.
  
  Parameters:
  
  items - the items that will be in the new observable ArrayList
  
  Returns:
  
  a newly created observableArrayList
  
  See Also:
  
  observableArrayList()
- observableArrayList
```
public static <E> ObservableList<E> observableArrayList(Collection<? extends E> col)
```
  Creates a new observable array list and adds a content of collection col to it.
  
  Parameters:
  
  col - a collection which content should be added to the observableArrayList
  
  Returns:
  
  a newly created observableArrayList
- observableHashMap
```
public static <K,V> ObservableMap<K,V> observableHashMap()
```
  Creates a new empty observable map that is backed by a HashMap.
  
  Type Parameters:
  
  K - the type of keys
  
  Returns:
  
  a newly created observable HashMap
- concat
```
public static <E> ObservableList<E> concat(ObservableList<E>... lists)
```
  Concatenates more observable lists into one. The resulting list would be backed by an arraylist.
  
  Parameters:
  
  lists - lists to concatenate
  
  Returns:
  
  new observable array list concatenated from the arguments
- unmodifiableObservableList
```
public static <E> ObservableList<E> unmodifiableObservableList(ObservableList<E> list)
```
  Creates and returns unmodifiable wrapper list on top of provided observable list.
  
  Parameters:
  
  list - an ObservableList that is to be wrapped
  
  Returns:
  
  an ObserableList wrapper that is unmodifiable
  
  See Also:
  
  Collections.unmodifiableList(java.util.List)
- checkedObservableList
```
public static <E> ObservableList<E> checkedObservableList(ObservableList<E> list,
                                                          Class<E> type)
```
  Creates and returns a typesafe wrapper on top of provided observable list.
  
  Parameters:
  
  list - an Observable list to be wrapped
  
  Returns:
  
  a dynamically typesafe view of the specified list
  
  See Also:
  
  Collections.checkedList(java.util.List, java.lang.Class)
- synchronizedObservableList
```
public static <E> ObservableList<E> synchronizedObservableList(ObservableList<E> list)
```
  Creates and returns a synchronized wrapper on top of provided observable list.
  
  Parameters:
  
  list - the list to be "wrapped" in a synchronized list.
  
  Returns:
  
  A synchronized version of the observable list
  
  See Also:
  
  Collections.synchronizedList(java.util.List)
- emptyObservableList
```
public static <E> ObservableList<E> emptyObservableList()
```
  Creates and empty unmodifiable observable list.
  
  Returns:
  
  An empty unmodifiable observable list
  
  See Also:
  
  Collections.emptyList()
- singletonObservableList
```
public static <E> ObservableList<E> singletonObservableList(E e)
```
  Creates an unmodifiable observable list with single element.
  
  Parameters:
  
  e - the only elements that will be contained in this singleton observable list
  
  Returns:
  
  a singleton observable list
  
  See Also:
  
  Collections.singletonList(java.lang.Object)
- unmodifiableObservableSet
```
public static <E> ObservableSet<E> unmodifiableObservableSet(ObservableSet<E> set)
```
  Creates and returns unmodifiable wrapper on top of provided observable set.
  
  Parameters:
  
  set - an ObservableSet that is to be wrapped
  
  Returns:
  
  an ObserableSet wrapper that is unmodifiable
  
  Since:
  
  JavaFX 8.0
  
  See Also:
  
  Collections.unmodifiableSet(java.util.Set)
- checkedObservableSet
```
public static <E> ObservableSet<E> checkedObservableSet(ObservableSet<E> set,
                                                        Class<E> type)
```
  Creates and returns a typesafe wrapper on top of provided observable set.
  
  Parameters:
  
  set - an Observable set to be wrapped
  
  Returns:
  
  a dynamically typesafe view of the specified set
  
  Since:
  
  JavaFX 8.0
  
  See Also:
  
  Collections.checkedSet(java.util.Set, java.lang.Class)
- synchronizedObservableSet
```
public static <E> ObservableSet<E> synchronizedObservableSet(ObservableSet<E> set)
```
  Creates and returns a synchronized wrapper on top of provided observable set.
  
  Parameters:
  
  set - the set to be "wrapped" in a synchronized set.
  
  Returns:
  
  A synchronized version of the observable set
  
  Since:
  
  JavaFX 8.0
  
  See Also:
  
  Collections.synchronizedSet(java.util.Set)
- emptyObservableSet
```
public static <E> ObservableSet<E> emptyObservableSet()
```
  Creates and empty unmodifiable observable set.
  
  Returns:
  
  An empty unmodifiable observable set
  
  Since:
  
  JavaFX 8.0
  
  See Also:
  
  Collections.emptySet()
- copy
```
public static <T> void copy(ObservableList<? super T> dest,
                            List<? extends T> src)
```
  Copies elements from src to dest. Fires only one change notification on dest.
  
  Parameters:
  
  dest - the destination observable list
  
  See Also:
  
  Collections.copy(java.util.List, java.util.List)
- fill
```
public static <T> void fill(ObservableList<? super T> list,
                            T obj)
```
  Fills the provided list with obj. Fires only one change notification on the list.
  
  Parameters:
  
  list - the list to fill
  
  See Also:
  
  Collections.fill(java.util.List, java.lang.Object)
- replaceAll
```
public static <T> boolean replaceAll(ObservableList<T> list,
                                     T oldVal,
                                     T newVal)
```
  Replace all oldVal elements in the list with newVal element. Fires only one change notification on the list.
  
  Parameters:
  
  list - the list which will have it's elements replaced
  
  Returns:
  
  true if the list was modified
  
  See Also:
  
  Collections.replaceAll(java.util.List, java.lang.Object, java.lang.Object)
- reverse
```
public static void reverse(ObservableList list)
```
  Reverse the order in the list Fires only one change notification on the list.
  
  Parameters:
  
  list - the list to be reversed
  
  See Also:
  
  Collections.reverse(java.util.List)
- rotate
```
public static void rotate(ObservableList list,
                          int distance)
```
  Rotates the list by distance. Fires only one change notification on the list.
  
  Parameters:
  
  list - the list to be rotated
  
  See Also:
  
  Collections.rotate(java.util.List, int)
- shuffle
```
public static void shuffle(ObservableList<?> list)
```
  Shuffles all elements in the observable list. Fires only one change notification on the list.
  
  Parameters:
  
  list - the list to shuffle
  
  See Also:
  
  Collections.shuffle(java.util.List)
- shuffle
```
public static void shuffle(ObservableList list,
                           Random rnd)
```
  Shuffles all elements in the observable list. Fires only one change notification on the list.
  
  Parameters:
  
  list - the list to be shuffled
  
  See Also:
  
  Collections.shuffle(java.util.List, java.util.Random)
- sort
```
public static <T extends Comparable<? super T>> void sort(ObservableList<T> list)
```
  Sorts the provided observable list. Fires only one change notification on the list.
  
  See Also:
  
  Collections.sort(java.util.List)
- sort
```
public static <T> void sort(ObservableList<T> list,
                            Comparator<? super T> c)
```
  Sorts the provided observable list using the c comparator. Fires only one change notification on the list.
  
  Parameters:
  
  list - the list to sort
  
  See Also:
  
  Collections.sort(java.util.List, java.util.Comparator)

© 2008, 2025, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from JavaFX API Documentation.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Java, JavaFX and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.

Class FXCollections

Method Summary

Methods inherited from class java.lang.Object

Method Detail

observableList

observableList

observableMap

observableSet

observableSet

unmodifiableObservableMap

checkedObservableMap

synchronizedObservableMap

emptyObservableMap

observableIntegerArray

observableIntegerArray

observableIntegerArray

observableFloatArray

observableFloatArray

observableFloatArray

observableArrayList

observableArrayList

observableArrayList

observableArrayList

observableHashMap

concat

unmodifiableObservableList

checkedObservableList

synchronizedObservableList

emptyObservableList

singletonObservableList

unmodifiableObservableSet

checkedObservableSet

synchronizedObservableSet

emptyObservableSet

copy

fill

replaceAll

reverse

rotate

shuffle

shuffle

sort

sort