1 package cz.cuni.amis.utils.collections;
2
3 import java.util.Collection;
4 import java.util.EventListener;
5
6 /**
7 * Listener on collection change events.
8 * @author Ik
9 * @param <E>
10 */
11 public interface CollectionEventListener<E> extends EventListener {
12
13 /**
14 * Called before the elements will be added to the collection.
15 * @param toBeAdded collection of items to be added, in case of one item this contains a collection with one item
16 * @param whereToAdd
17 */
18 void preAddEvent(Collection<E> toBeAdded, Collection<E> whereToAdd);
19
20 /**
21 * Called after the elements were added to the collection.
22 * @param alreadyAdded
23 * @param whereWereAdded
24 */
25 void postAddEvent(Collection<E> alreadyAdded, Collection<E> whereWereAdded);
26
27 /**
28 * Called before the elements will be removed from the collection.
29 * @param toBeRemoved
30 * @param whereToRemove
31 */
32 void preRemoveEvent(Collection<E> toBeRemoved, Collection<E> whereToRemove);
33
34 /**
35 * Called after the elements were removed from the collection.
36 * @param alreadyAdded
37 * @param whereWereRemoved
38 */
39 void postRemoveEvent(Collection<E> alreadyAdded, Collection<E> whereWereRemoved);
40 }