--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/org.eclipse.jface/src/org/eclipse/jface/commands/ToggleState.d	Sat Mar 14 18:23:29 2009 +0100
@@ -0,0 +1,77 @@
+/*******************************************************************************
+ * Copyright (c) 2005, 2006 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
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+
+module org.eclipse.jface.commands.ToggleState;
+
+import org.eclipse.jface.menus.IMenuStateIds;
+import org.eclipse.jface.preference.IPreferenceStore;
+
+import org.eclipse.jface.commands.PersistentState;
+
+import java.lang.all;
+import java.util.Set;
+
+/**
+ * <p>
+ * A piece of state storing a {@link Boolean}.
+ * </p>
+ * <p>
+ * If this state is registered using {@link IMenuStateIds#STYLE}, then it will
+ * control the presentation of the command if displayed in the menus, tool bars
+ * or status line.
+ * </p>
+ * <p>
+ * Clients may instantiate this class, but must not extend.
+ * </p>
+ *
+ * @since 3.2
+ */
+public class ToggleState : PersistentState {
+
+    /**
+     * Constructs a new <code>ToggleState</code>. By default, the toggle is
+     * off (e.g., <code>false</code>).
+     */
+    public this() {
+        setValue(Boolean.FALSE);
+    }
+
+    public override final void load(IPreferenceStore store,
+            String preferenceKey) {
+        bool currentValue = (cast(Boolean) getValue()).booleanValue();
+        store.setDefault(preferenceKey, currentValue);
+        if (shouldPersist() && (store.contains(preferenceKey))) {
+            bool value = store.getBoolean(preferenceKey);
+            setValue(value ? Boolean.TRUE : Boolean.FALSE);
+        }
+    }
+
+    public override final void save(IPreferenceStore store,
+            String preferenceKey) {
+        if (shouldPersist()) {
+            Object value = getValue();
+            if ( auto v = cast(Boolean)value ) {
+                store.setValue(preferenceKey, v.booleanValue());
+            }
+        }
+    }
+
+    public override void setValue(Object value) {
+        if (!(cast(Boolean)value)) {
+            throw new IllegalArgumentException(
+                    "ToggleState takes a Boolean as a value"); //$NON-NLS-1$
+        }
+
+        super.setValue(value);
+    }
+}