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

  • 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