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diff --git a/common/plugins/org.eclipse.jpt.common.ui/src/org/eclipse/jpt/common/ui/jface/ItemStructuredContentProvider.java b/common/plugins/org.eclipse.jpt.common.ui/src/org/eclipse/jpt/common/ui/jface/ItemStructuredContentProvider.java
new file mode 100644
index 0000000000..0ddbfe980c
--- /dev/null
+++ b/common/plugins/org.eclipse.jpt.common.ui/src/org/eclipse/jpt/common/ui/jface/ItemStructuredContentProvider.java
@@ -0,0 +1,105 @@
+/*******************************************************************************
+ * Copyright (c) 2008, 2012 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.ui.jface;
+
+import java.io.Serializable;
+import org.eclipse.jpt.common.utility.internal.StringTools;
+
+/**
+ * Implementations of this interface can be used to maintain the elements
+ * of a specific input element. The implementation will monitor
+ * the item for any changes that affect the elements and forward them
+ * appropriately to the {@link Manager}.
+ * <p>
+ * Provisional API: This interface is part of an interim API that is still
+ * under development and expected to change significantly before reaching
+ * stability. It is available at this early stage to solicit feedback from
+ * pioneering adopters on the understanding that any code that uses this API
+ * will almost certainly be broken (repeatedly) as the API evolves.
+ * 
+ * @see org.eclipse.jface.viewers.IContentProvider
+ * @see org.eclipse.jface.viewers.IStructuredContentProvider
+ */
+public interface ItemStructuredContentProvider {
+	/**
+	 * Return the input element's elements.
+	 * <strong>NB:</strong>
+	 * When this method is called, the item is an <em>input</em> element.
+	 * 
+	 * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer, Object, Object)
+	 * @see org.eclipse.jface.viewers.IStructuredContentProvider#getElements(Object)
+	 * @see org.eclipse.jface.viewers.ITreeContentProvider#getElements(Object)
+	 * @see org.eclipse.jface.viewers.ITreeContentProvider#getChildren(Object)
+	 */
+	Object[] getElements();
+
+	/**
+	 * Dispose the item content provider.
+	 * Remove any item listeners as appropriate.
+	 */
+	void dispose();
+
+
+	/**
+	 * Convenience constant for when no children are present.
+	 */
+	Object[] EMPTY_ARRAY = new Object[0];
+
+
+	/**
+	 * An item structured content provider's manager is notified whenever the
+	 * input element's elements have changed.
+	 */
+	interface Manager {
+		/**
+		 * The elements for the specified input element have changed.
+		 * Update appropriately.
+		 */
+		void updateElements(Object inputElement);
+
+		/**
+		 * The specified element has been removed from the input element.
+		 * Dispose of the element's providers, if necessary.
+		 */
+		void dispose(Object element);
+	}
+
+
+	/**
+	 * A "null" item structured content provider that has no elements.
+	 */
+	final class Null
+		implements ItemStructuredContentProvider, Serializable
+	{
+		public static final ItemStructuredContentProvider INSTANCE = new Null();
+		public static ItemStructuredContentProvider instance() {
+			return INSTANCE;
+		}
+		// ensure single instance
+		private Null() {
+			super();
+		}
+		public Object[] getElements() {
+			return EMPTY_ARRAY;
+		}
+		public void dispose() {
+			// NOP
+		}
+		@Override
+		public String toString() {
+			return StringTools.buildSingletonToString(this);
+		}
+		private static final long serialVersionUID = 1L;
+		private Object readResolve() {
+			// replace this object with the singleton
+			return INSTANCE;
+		}
+	}
+}