add Comparator constructor to PriorityQueue

1 files changed, 15 insertions, 2 deletions

diff --git a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/collection/PriorityQueue.java b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/collection/PriorityQueue.java
index 98f5f9584b..fdc389dd2a 100644
--- a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/collection/PriorityQueue.java
+++ b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/collection/PriorityQueue.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2013 Oracle. All rights reserved.
+ * Copyright (c) 2013, 2015 Oracle. All rights reserved.
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v1.0, which accompanies this distribution
  * and is available at http://www.eclipse.org/legal/epl-v10.html.
@@ -10,13 +10,16 @@
 package org.eclipse.jpt.common.utility.internal.collection;
 
 import java.io.Serializable;
+import java.util.Comparator;
 import java.util.SortedSet;
+import java.util.TreeSet;
 import org.eclipse.jpt.common.utility.collection.Queue;
 
 /**
  * Adapt a {@link SortedSet} to create a priority implementation of the
  * {@link Queue} interface. Elements will dequeue in the order determined by
- * wrapped sorted set.
+ * wrapped sorted set (i.e. {@link #dequeue} will return the element returned
+ * by {@link SortedSet#first}.
  * @param <E> the type of elements maintained by the queue
  */
 public class PriorityQueue<E>
@@ -27,6 +30,16 @@ public class PriorityQueue<E>
 	private static final long serialVersionUID = 1L;
 
 
+	/**
+	 * Construct a priority queue that uses the specified comparator
+	 * to determine the order elements will be dequeued
+	 * (i.e. {@link #dequeue} will return the current element with
+	 * the lowest position, as specified by the comparator).
+	 */
+	public PriorityQueue(Comparator<? super E> comparator) {
+		this(new TreeSet<E>(comparator));
+	}
+
 	public PriorityQueue(SortedSet<E> elements) {
 		super();
 		if (elements == null) {