ObservableArray — OpenJavaFX 11

Type Parameters:

T - actual array instance type

All Superinterfaces:

Observable

All Known Subinterfaces:

ObservableFaceArray, ObservableFloatArray, ObservableIntegerArray

All Known Implementing Classes:

ObservableArrayBase
```
public interface ObservableArray<T extends ObservableArray<T>>
extends Observable
```
ObservableArray is an array that allows listeners to track changes when they occur. In order to track changes, the internal array is encapsulated and there is no direct access available from the outside. Bulk operations are supported but they always do a copy of the data range. You can find them in subclasses as they deal with primitive arrays directly.
Implementations have both capacity, which is internal array length, and size. If size needs to be increased beyond capacity, the capacity increases to match that new size. Use trimToSize() method to shrink it.

Since:

JavaFX 8.0

See Also:

ArrayChangeListener

Method Summary

All MethodsInstance MethodsAbstract Methods
Modifier and Type	Method	Description
`void`	`addListener(ArrayChangeListener<T> listener)`	Add a listener to this observable array.
`void`	`clear()`	Empties the array by resizing it to 0.
`void`	`ensureCapacity(int capacity)`	Grows the capacity of this array if the current capacity is less than given `capacity`, does nothing if it already exceeds the `capacity`.
`void`	`removeListener(ArrayChangeListener<T> listener)`	Tries to remove a listener from this observable array.
`void`	`resize(int size)`	Sets new length of data in this array.
`int`	`size()`	Retrieves length of data in this array.
`void`	`trimToSize()`	Shrinks the capacity to the current size of data in the array.

Methods inherited from interface javafx.beans.Observable
addListener, removeListener

Method Detail
- addListener
```
void addListener(ArrayChangeListener<T> listener)
```
  Add a listener to this observable array.
  
  Parameters:
  
  listener - the listener for listening to the array changes
  
  Throws:
  
  NullPointerException - if listener is null
- removeListener
```
void removeListener(ArrayChangeListener<T> listener)
```
  Tries to remove a listener from this observable array. If the listener is not attached to this array, nothing happens.
  
  Parameters:
  
  listener - a listener to remove
  
  Throws:
  
  NullPointerException - if listener is null
- resize
```
void resize(int size)
```
  Sets new length of data in this array. This method grows capacity if necessary but never shrinks it. Resulting array will contain existing data for indexes that are less than the current size and zeroes for indexes that are greater than the current size.
  
  Parameters:
  
  size - new length of data in this array
  
  Throws:
  
  NegativeArraySizeException - if size is negative
- ensureCapacity
```
void ensureCapacity(int capacity)
```
  Grows the capacity of this array if the current capacity is less than given capacity, does nothing if it already exceeds the capacity.
  
  Parameters:
  
  capacity - the capacity of this array
- trimToSize
```
void trimToSize()
```
  Shrinks the capacity to the current size of data in the array.
- clear
```
void clear()
```
  Empties the array by resizing it to 0. Capacity is not changed.
  
  See Also:
  
  trimToSize()
- size
```
int size()
```
  Retrieves length of data in this array.
  
  Returns:
  
  length of data in this array

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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.

Interface ObservableArray<T extends ObservableArray<T>>

Method Summary

Methods inherited from interface javafx.beans.Observable

Method Detail

addListener

removeListener

resize

ensureCapacity

trimToSize

clear

size