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root/jsr166/jsr166/src/main/java/util/Queue.java

Comparing jsr166/src/main/java/util/Queue.java (file contents):
Revision 1.2 by tim, Sun May 18 18:10:02 2003 UTC vs.
Revision 1.5 by dl, Sun Jun 8 00:44:20 2003 UTC

#	Line 1 | Line 1
1	+	/*
2	+	* Written by Doug Lea with assistance from members of JCP JSR-166
3	+	* Expert Group and released to the public domain. Use, modify, and
4	+	* redistribute this code in any way without acknowledgement.
5	+	*/
6	+
7		package java.util;
8
9		/**
#	Line 6 | Line 12 | package java.util;
12		* additional insertion, extraction, and inspection operations.
13		*
14		* <p>Queues typically, but do not necessarily, order elements in a
15	<	* FIFO (first-in-first-out) manner.  Among the exceptions are priority
16	<	* queues, which order elements according to a supplied comparators, or
17	<	* the elements natural ordering.  Every Queue implementation must specify
18	<	* its ordering guarantees.
15	>	* FIFO (first-in-first-out) manner.  Among the exceptions are
16	>	* priority queues, which order elements according to a supplied
17	>	* comparator, or the elements' natural ordering.  Every Queue
18	>	* implementation must specify its ordering guarantees.
19		*
20		* <p>The {@link #offer(E)} method adds an element if possible, otherwise
21		* returning <tt>false</tt>.  This differs from the {@link
#	Line 17 | Line 23 | package java.util;
23		* failure. It is designed for use in collections in which failure to
24		* add is a normal, rather than exceptional occurrence, for example,
25		* in fixed-capacity (or &ldquo;bounded&rdquo;) queues.
26	<	*
26	>
27	>	*
28		* <p>The {@link #remove()} and {@link #poll()} methods remove and return an
29	<	* element in accord with the implementation's ordering policy. For example,
30	<	* in FIFO queues, they remove and return the oldest element in the queue.
29	>	* element in accord with the implementation's ordering policy.
30	>	* Exactly which element is removed from the queue is a function
31	>	* of the queue's ordering policy, which differs from implementation
32	>	* to implementation.  Possible orderings include (but are not limited
33	>	* to) first-in-first-out (FIFO), element priority, and arbitrary.
34		* The <tt>remove()</tt> and <tt>poll()</tt> methods differ only in their
35		* behavior when the queue is empty: the <tt>remove()</tt> method throws an
36		* exception, while the <tt>poll()</tt> method returns <tt>null</tt>.
#	Line 65 | Line 75 | public interface Queue<E> extends Collec
75
76		/**
77		* Remove and return an element from the queue if one is available.
68	–	* Exactly which element is removed from the queue is a function
69	–	* of the queue's ordering policy, which differs from implementation
70	–	* to implementation.  Possible orderings include (but are not limited
71	–	* to) first-in-first-out (FIFO), element priority, and arbitrary.
78		*
79		* @return an element previously on the queue, or <tt>null</tt> if the
80	<	*         queue is empty.
80	>	*         queue is empty.
81		*/
82		public E poll();
83
84		/**
85		* Remove and return an element from the queue.  This method differs
86		* from the <tt>poll</tt> method in that it throws an exception if the
87	<	* queue is empty.
87	>	* queue is empty.
88		*
89		* @return an element previously on the queue.
90		* @throws NoSuchElementException if the queue is empty.

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