Скачать или смотреть Core Java -Episode 22 b/i (Collections - methods of Collection interface)

1 public boolean add(E e) It is used to insert an element in this collection.
2 public boolean addAll(Collection c) It is used to insert the specified collection elements in the invoking collection.
3 public boolean remove(Object element) It is used to delete an element from the collection.
4 public boolean removeAll(Collection c) It is used to delete all the elements of the specified collection from the invoking collection.
5 public boolean retainAll(Collection c) It is used to delete all the elements of invoking collection except the specified collection.
6 public int size() It returns the total number of elements in the collection.
7 public void clear() It removes the total number of elements from the collection.
8 public boolean contains(Object element) It is used to search an element.
9 public boolean containsAll(Collection c) It is used to search the specified collection in the collection.

10 public Object[] toArray() It converts collection into array.
11 public boolean isEmpty() It checks if collection is empty.