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diff --git a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/deque/PriorityDeque.java b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/deque/PriorityDeque.java
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index 0000000000..270b04af78
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+++ b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/deque/PriorityDeque.java
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+/*******************************************************************************
+ * 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.
+ * 
+ * Contributors:
+ *     Oracle - initial API and implementation
+ ******************************************************************************/
+package org.eclipse.jpt.common.utility.internal.deque;
+
+import java.util.Comparator;
+import org.eclipse.jpt.common.utility.deque.InputRestrictedDeque;
+
+/**
+ * Resizable priority implementation of the {@link InputRestrictedDeque} interface.
+ * Elements will dequeue from the deque's head in the order determined by a comparator
+ * (i.e. {@link #dequeueHead} will return the element sorted first
+ * while {@link #dequeueTail} will return the element sorted last).
+ * @param <E> the type of elements maintained by the deque
+ * @see FixedCapacityPriorityDeque
+ * @see DequeTools
+ */
+public class PriorityDeque<E>
+	extends AbstractPriorityDeque<E>
+{
+	private static final long serialVersionUID = 1L;
+
+
+	// ********** constructors **********
+
+	/**
+	 * Construct an empty priority deque with the specified comparator
+	 * and initial capacity.
+	 */
+	public PriorityDeque(Comparator<? super E> comparator, int initialCapacity) {
+		super(comparator, initialCapacity);
+	}
+
+
+	// ********** Deque implementation **********
+
+	@Override
+	public void enqueue(E element) {
+		this.ensureCapacity(this.size + 1);
+		super.enqueue(element);
+	}
+
+	/**
+	 * Increase the deque's capacity, if necessary, to ensure it has at least
+	 * the specified minimum capacity.
+	 */
+	public void ensureCapacity(int minCapacity) {
+		int oldCapacity = this.elements.length - 1;
+		if (oldCapacity < minCapacity) {
+			int newCapacity = ((oldCapacity * 3) >> 1) + 1;
+			if (newCapacity < minCapacity) {
+				newCapacity = minCapacity;
+			}
+			this.elements = this.copyElements(newCapacity);
+		}
+	}
+
+	/**
+	 * Decrease the deque's capacity, if necessary, to match its current size.
+	 */
+	public void trimToSize() {
+		if (this.elements.length > this.size + 1) {
+			this.elements = this.copyElements(this.size);
+		}
+	}
+
+	private E[] copyElements(int newCapacity) {
+		@SuppressWarnings("unchecked")
+		E[] newElements = (E[]) new Object[newCapacity + 1];
+		System.arraycopy(this.elements, 1, newElements, 1, this.size); // skip 0
+		return newElements;
+	}
+
+
+	// ********** standard methods **********
+
+	@Override
+	public PriorityDeque<E> clone() {
+		return (PriorityDeque<E>) super.clone();
+	}
+}