--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/observable/masterdetail/DetailObservableValue.d	Tue Apr 14 11:35:29 2009 +0200
@@ -0,0 +1,138 @@
+/*******************************************************************************
+ * Copyright (c) 2005, 2007 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
+ *     Brad Reynolds - bug 164653
+ *     Brad Reynolds - bug 147515
+ *******************************************************************************/
+module org.eclipse.core.internal.databinding.observable.masterdetail.DetailObservableValue;
+
+import java.lang.all;
+
+import org.eclipse.core.databinding.observable.Diffs;
+import org.eclipse.core.databinding.observable.IObserving;
+import org.eclipse.core.databinding.observable.masterdetail.IObservableFactory;
+import org.eclipse.core.databinding.observable.value.AbstractObservableValue;
+import org.eclipse.core.databinding.observable.value.IObservableValue;
+import org.eclipse.core.databinding.observable.value.IValueChangeListener;
+import org.eclipse.core.databinding.observable.value.ValueChangeEvent;
+import org.eclipse.core.runtime.Assert;
+
+/**
+ * @since 1.0
+ * 
+ */
+public class DetailObservableValue : AbstractObservableValue , IObserving {
+
+    private bool updating = false;
+
+    private IValueChangeListener innerChangeListener = new class() IValueChangeListener {
+        public void handleValueChange(ValueChangeEvent event) {
+            if (!updating) {
+                fireValueChange(event.diff);
+            }
+        }
+    };
+
+    private Object currentOuterValue;
+
+    private IObservableValue innerObservableValue;
+
+    private Object detailType;
+
+    private IObservableValue outerObservableValue;
+
+    private IObservableFactory factory;
+
+    /**
+     * @param outerObservableValue
+     * @param factory
+     * @param detailType
+     */
+    public this(IObservableValue outerObservableValue,
+            IObservableFactory factory, Object detailType) {
+        super(outerObservableValue.getRealm());
+        this.factory = factory;
+        this.detailType = detailType;
+        this.outerObservableValue = outerObservableValue;
+        updateInnerObservableValue(outerObservableValue);
+
+        outerObservableValue.addValueChangeListener(outerChangeListener);
+    }
+
+    IValueChangeListener outerChangeListener = new class() IValueChangeListener {
+        public void handleValueChange(ValueChangeEvent event) {
+            Object oldValue = doGetValue();
+            updateInnerObservableValue(outerObservableValue);
+            fireValueChange(Diffs.createValueDiff(oldValue, doGetValue()));
+        }
+    };
+
+    private void updateInnerObservableValue(
+            IObservableValue outerObservableValue) {
+        currentOuterValue = outerObservableValue.getValue();
+        if (innerObservableValue !is null) {
+            innerObservableValue.removeValueChangeListener(innerChangeListener);
+            innerObservableValue.dispose();
+        }
+        if (currentOuterValue is null) {
+            innerObservableValue = null;
+        } else {
+            this.innerObservableValue = cast(IObservableValue) factory
+                    .createObservable(currentOuterValue);
+            Object innerValueType = innerObservableValue.getValueType();
+
+            if (detailType !is null) {
+                Assert
+                        .isTrue(
+                                detailType.equals(innerValueType),
+                                "Cannot change value type in a nested observable value, from " + innerValueType + " to " + detailType); //$NON-NLS-1$ //$NON-NLS-2$
+            }
+            innerObservableValue.addValueChangeListener(innerChangeListener);
+        }
+    }
+
+    public void doSetValue(Object value) {
+        if (innerObservableValue !is null)
+            innerObservableValue.setValue(value);
+    }
+
+    public Object doGetValue() {
+        return innerObservableValue is null ? null : innerObservableValue
+                .getValue();
+    }
+
+    public Object getValueType() {
+        return detailType;
+    }
+
+    public void dispose() {
+        super.dispose();
+
+        if (outerObservableValue !is null) {
+            outerObservableValue.removeValueChangeListener(outerChangeListener);
+            outerObservableValue.dispose();
+        }
+        if (innerObservableValue !is null) {
+            innerObservableValue.removeValueChangeListener(innerChangeListener);
+            innerObservableValue.dispose();
+        }
+        currentOuterValue = null;
+        factory = null;
+        innerObservableValue = null;
+        innerChangeListener = null;
+    }
+
+    public Object getObserved() {
+        if ( null !is cast(IObserving)innerObservableValue ) {
+            return (cast(IObserving)innerObservableValue).getObserved();
+        }
+        return null;
+    }
+
+}