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diff --git a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/TransformationPropertyValueModel.java b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/TransformationPropertyValueModel.java
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+++ b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/TransformationPropertyValueModel.java
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+/*******************************************************************************
+ * Copyright (c) 2007, 2010 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.model.value;
+
+import org.eclipse.jpt.common.utility.internal.Transformer;
+import org.eclipse.jpt.common.utility.model.event.PropertyChangeEvent;
+import org.eclipse.jpt.common.utility.model.value.PropertyValueModel;
+
+/**
+ * A <code>TransformationPropertyValueModel</code> wraps another
+ * {@link PropertyValueModel} and uses a {@link Transformer}
+ * to transform the wrapped value before it is returned by {@link #getValue()}.
+ * <p>
+ * As an alternative to building a {@link Transformer},
+ * a subclass of <code>TransformationPropertyValueModel</code> can
+ * either override {@link #transform_(Object)} or,
+ * if something other than null should be returned when the wrapped value
+ * is null, override {@link #transform(Object)}.
+ * 
+ * @see Transformer
+ */
+public class TransformationPropertyValueModel<T1, T2>
+	extends PropertyValueModelWrapper<T1>
+	implements PropertyValueModel<T2>
+{
+	protected final Transformer<T1, T2> transformer;
+
+
+	// ********** constructors/initialization **********
+
+	/**
+	 * Construct a property value model with the specified nested
+	 * property value model and the default transformer.
+	 * Use this constructor if you want to override
+	 * {@link #transform_(Object)} or {@link #transform(Object)}
+	 * method instead of building a {@link Transformer}.
+	 */
+	public TransformationPropertyValueModel(PropertyValueModel<? extends T1> valueHolder) {
+		super(valueHolder);
+		this.transformer = this.buildTransformer();
+	}
+
+	/**
+	 * Construct a property value model with the specified nested
+	 * property value model and transformer.
+	 */
+	public TransformationPropertyValueModel(PropertyValueModel<? extends T1> valueHolder, Transformer<T1, T2> transformer) {
+		super(valueHolder);
+		this.transformer = transformer;
+	}
+
+	protected Transformer<T1, T2> buildTransformer() {
+		return new DefaultTransformer();
+	}
+
+
+	// ********** PropertyValueModel implementation **********
+
+	public T2 getValue() {
+		// transform the object returned by the nested value model before returning it
+		return this.transform(this.valueHolder.getValue());
+	}
+
+
+	// ********** PropertyValueModelWrapper implementation **********
+
+	@Override
+	protected void valueChanged(PropertyChangeEvent event) {
+		// transform the values before propagating the change event
+	    @SuppressWarnings("unchecked")
+	    T1 eventOldValue = (T1) event.getOldValue();
+		Object oldValue = this.transformOld(eventOldValue);
+	    @SuppressWarnings("unchecked")
+	    T1 eventNewValue = (T1) event.getNewValue();
+		Object newValue = this.transformNew(eventNewValue);
+		this.firePropertyChanged(VALUE, oldValue, newValue);
+	}
+
+
+	// ********** behavior **********
+
+	/**
+	 * Transform the specified value and return the result.
+	 * This is called by
+	 * {@link #getValue()},
+	 * {@link #transformOld(Object)}, and
+	 * {@link #transformNew(Object)}.
+	 */
+	protected T2 transform(T1 value) {
+		return this.transformer.transform(value);
+	}
+
+	/**
+	 * Transform the specified, non-null, value and return the result.
+	 */
+	protected T2 transform_(@SuppressWarnings("unused") T1 value) {
+		throw new RuntimeException("This method was not overridden."); //$NON-NLS-1$
+	}
+
+	/**
+	 * Transform the specified old value and return the result.
+	 * By default, call {@link #transform(Object)}.
+	 * This is called by {@link #valueChanged(PropertyChangeEvent)}.
+	 */
+	protected T2 transformOld(T1 value) {
+		return this.transform(value);
+	}
+	
+	/**
+	 * Transform the specified new value and return the result.
+	 * By default, call {@link #transform(Object)}.
+	 * This is called by {@link #valueChanged(PropertyChangeEvent)}.
+	 */
+	protected T2 transformNew(T1 value) {
+		return this.transform(value);
+	}
+
+	@Override
+	public void toString(StringBuilder sb) {
+		sb.append(this.getValue());
+	}
+
+
+	// ********** default transformer **********
+
+	/**
+	 * The default transformer will return null if the wrapped value is null.
+	 * If the wrapped value is not null, it is transformed by a subclass
+	 * implementation of {@link TransformationPropertyValueModel#transform_(Object)}.
+	 */
+	protected class DefaultTransformer implements Transformer<T1, T2> {
+		public T2 transform(T1 value) {
+			return (value == null) ? null : TransformationPropertyValueModel.this.transform_(value);
+		}
+	}
+
+}