--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/org.eclipse.jface/src/org/eclipse/jface/commands/PersistentState.d	Sat Mar 14 18:23:29 2009 +0100
@@ -0,0 +1,89 @@
+/*******************************************************************************
+ * 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.PersistentState;
+
+import org.eclipse.core.commands.State;
+import org.eclipse.jface.preference.IPreferenceStore;
+
+import java.lang.all;
+import java.util.Set;
+
+/**
+ * <p>
+ * This is a state that can be made persistent. A state is persisted to a
+ * preference store.
+ * </p>
+ * <p>
+ * Clients may extend this class.
+ * </p>
+ *
+ * @since 3.2
+ */
+public abstract class PersistentState : State {
+
+    /**
+     * Whether this state should be persisted.
+     */
+    private bool persisted;
+
+    /**
+     * Loads this state from the preference store, given the location at which
+     * to look. This method must be symmetric with a call to
+     * {@link #save(IPreferenceStore, String)}.
+     *
+     * @param store
+     *            The store from which to read; must not be <code>null</code>.
+     * @param preferenceKey
+     *            The key at which the state is stored; must not be
+     *            <code>null</code>.
+     */
+    public abstract void load(IPreferenceStore store,
+            String preferenceKey);
+
+    /**
+     * Saves this state to the preference store, given the location at which to
+     * write. This method must be symmetric with a call to
+     * {@link #load(IPreferenceStore, String)}.
+     *
+     * @param store
+     *            The store to which the state should be written; must not be
+     *            <code>null</code>.
+     * @param preferenceKey
+     *            The key at which the state should be stored; must not be
+     *            <code>null</code>.
+     */
+    public abstract void save(IPreferenceStore store,
+            String preferenceKey);
+
+    /**
+     * Sets whether this state should be persisted.
+     *
+     * @param persisted
+     *            Whether this state should be persisted.
+     */
+    public void setShouldPersist(bool persisted) {
+        this.persisted = persisted;
+    }
+
+    /**
+     * Whether this state should be persisted. Subclasses should check this
+     * method before loading or saving.
+     *
+     * @return <code>true</code> if this state should be persisted;
+     *         <code>false</code> otherwise.
+     */
+    public bool shouldPersist() {
+        return persisted;
+    }
+}