Module javafx.base
Package javafx.collections

## Class SetChangeListener.Change<E>

- java.lang.Object
- - javafx.collections.SetChangeListener.Change<E>

- Type Parameters:
    `E` - element type
  Enclosing interface:
    SetChangeListener<E>

      public abstract static class SetChangeListener.Change<E>
      extends Object

  An elementary change done to an ObservableSet. Change contains information about an add or remove operation. Note that adding element that is already in the set does not modify the set and hence no change will be generated.
  Since:
    JavaFX 2.1

- - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `Change​(ObservableSet<E> set)` | Constructs a change associated with a set.

  - ### Method Summary

    All Methods Instance Methods Abstract Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `abstract E` | `getElementAdded()` | Get the new element.
    `abstract E` | `getElementRemoved()` | Get the old element.
    `ObservableSet<E>` | `getSet()` | An observable set that is associated with the change.
    `abstract boolean` | `wasAdded()` | If this change is a result of add operation.
    `abstract boolean` | `wasRemoved()` | If this change is a result of removal operation.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### Change

          public Change​(ObservableSet<E> set)

      Constructs a change associated with a set.
      Parameters:
        `set` - the source of the change

  - ### Method Detail

    - #### getSet

          public ObservableSet<E> getSet()

      An observable set that is associated with the change.
      Returns:
        the source set

    - #### wasAdded

          public abstract boolean wasAdded()

      If this change is a result of add operation.
      Returns:
        true if a new element was added to the set

    - #### wasRemoved

          public abstract boolean wasRemoved()

      If this change is a result of removal operation.
      Returns:
        true if an old element was removed from the set

    - #### getElementAdded

          public abstract E getElementAdded()

      Get the new element. Return null if this is a removal.
      Returns:
        the element that was just added

    - #### getElementRemoved

          public abstract E getElementRemoved()

      Get the old element. Return null if this is an addition.
      Returns:
        the element that was just removed