1 files changed, 91 insertions, 0 deletions
diff --git a/testplugins/org.eclipse.jdt.ui.tests/leaks/org/eclipse/jdt/ui/leaktest/reftracker/FIFOQueue.java b/testplugins/org.eclipse.jdt.ui.tests/leaks/org/eclipse/jdt/ui/leaktest/reftracker/FIFOQueue.java
new file mode 100644
index 000000000..e7280bf7c
--- /dev/null
+++ b/testplugins/org.eclipse.jdt.ui.tests/leaks/org/eclipse/jdt/ui/leaktest/reftracker/FIFOQueue.java
@@ -0,0 +1,91 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2008 IBM Corporation and others.
+ * 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:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.jdt.ui.leaktest.reftracker;
+
+import java.util.Arrays;
+
+
+public class FIFOQueue {
+
+	private Object[] fStore;
+	private int fReadIndex;
+	private int fWriteIndex;
+
+	public FIFOQueue(int initialSize) {
+		fStore= new Object[initialSize];
+		fReadIndex= 0;
+		fWriteIndex= 0;
+	}
+
+	public void add(Object object) {
+		int pos= fWriteIndex;
+		int next= nextIndex(pos, fStore.length);
+		if (next == fReadIndex) {
+			pos= increaseCapacity();
+			next= pos + 1;
+		}
+		fStore[pos]= object;
+		fWriteIndex= next;
+	}
+
+	private int increaseCapacity() {
+		Object[] oldStore= fStore;
+		int oldLen= oldStore.length;
+		Object[] newStore= new Object[oldLen * 2];
+		int k= 0;
+		for (int i= fReadIndex, end= fWriteIndex; i != end; i= nextIndex(i, oldLen), k++) {
+			newStore[k]= oldStore[i];
+			oldStore[i]= null;
+		}
+		fStore= newStore;
+		fReadIndex= 0;
+		fWriteIndex= k;
+		return k;
+	}
+
+	public Object poll() {
+		if (isEmpty()) {
+			return null;
+		}
+		int index= fReadIndex;
+		Object element= fStore[index];
+		fStore[index]= null; // avoid unnecessary references
+		fReadIndex= nextIndex(index, fStore.length);
+		return element;
+	}
+
+	private static int nextIndex(int index, int max) {
+		int next= index + 1;
+		if (next == max) {
+			return 0;
+		}
+		return next;
+	}
+
+	public boolean isEmpty() {
+		return fReadIndex == fWriteIndex;
+	}
+
+	public int getSize() {
+		if (fReadIndex <= fWriteIndex) {
+			return fWriteIndex - fReadIndex;
+		} else {
+			return fStore.length - fReadIndex + fWriteIndex;
+		}
+	}
+
+	public void clear() {
+		Arrays.fill(fStore, null);
+		fReadIndex= 0;
+		fWriteIndex= 0;
+	}
+}