- /*
- * Copyright 2001-2004 The Apache Software Foundation
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.apache.commons.collections;
-
- /**
- * Defines a collection for priority queues, which can insert, peek and pop.
- * <p>
- * This interface is now replaced by the <code>Buffer</code> interface.
- *
- * @deprecated Replaced by the Buffer interface and implementations in buffer subpackage.
- * Due to be removed in v4.0.
- * @since Commons Collections 1.0
- * @version $Revision: 1.14 $ $Date: 2004/02/18 01:15:42 $
- *
- * @author Peter Donald
- */
- public interface PriorityQueue {
-
- /**
- * Clear all elements from queue.
- */
- void clear();
-
- /**
- * Test if queue is empty.
- *
- * @return true if queue is empty else false.
- */
- boolean isEmpty();
-
- /**
- * Insert an element into queue.
- *
- * @param element the element to be inserted
- *
- * @throws ClassCastException if the specified <code>element</code>'s
- * type prevents it from being compared to other items in the queue to
- * determine its relative priority.
- */
- void insert(Object element);
-
- /**
- * Return element on top of heap but don't remove it.
- *
- * @return the element at top of heap
- * @throws java.util.NoSuchElementException if <code>isEmpty() == true</code>
- */
- Object peek();
-
- /**
- * Return element on top of heap and remove it.
- *
- * @return the element at top of heap
- * @throws java.util.NoSuchElementException if <code>isEmpty() == true</code>
- */
- Object pop();
-
- }