| 11 |
|
* element based on offer, poll, and peek, respectively but that throw |
| 12 |
|
* exceptions instead of indicating failure via false or null returns. |
| 13 |
|
* The provided implementations all assume that the base implementation |
| 14 |
< |
* does <em>not</em> allow null elements. |
| 14 |
> |
* does <em>not</em> allow <tt>null</tt> elements. |
| 15 |
> |
* @since 1.5 |
| 16 |
> |
* @author Doug Lea |
| 17 |
|
*/ |
| 18 |
< |
|
| 18 |
> |
|
| 19 |
|
public abstract class AbstractQueue<E> extends AbstractCollection<E> implements Queue<E> { |
| 20 |
|
|
| 21 |
|
public boolean add(E x) { |
| 25 |
|
throw new IllegalStateException("Queue full"); |
| 26 |
|
} |
| 27 |
|
|
| 28 |
< |
public E remove() { |
| 28 |
> |
public E remove() throws NoSuchElementException { |
| 29 |
|
E x = poll(); |
| 30 |
|
if (x != null) |
| 31 |
|
return x; |
| 33 |
|
throw new NoSuchElementException(); |
| 34 |
|
} |
| 35 |
|
|
| 36 |
< |
public E element() { |
| 36 |
> |
public E element() throws NoSuchElementException { |
| 37 |
|
E x = peek(); |
| 38 |
|
if (x != null) |
| 39 |
|
return x; |
| 46 |
|
; |
| 47 |
|
} |
| 48 |
|
|
| 49 |
+ |
// XXX Remove this redundant declaration, pending response from Neal Gafter. |
| 50 |
+ |
public abstract Iterator<E> iterator(); |
| 51 |
|
} |
| 52 |
+ |
|
| 53 |
+ |
|
| 54 |
+ |
|
| 55 |
+ |
|
| 56 |
+ |
|
