Module javafx.base

Package javafx.collections

Interface ObservableArray<T extends ObservableArray<T>>

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

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 declared in interface javafx.beans.Observable

addListener, removeListener, subscribe

Method Details

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