| 1 | /******************************************************************************* |
| 2 | * Copyright (c) 2005, 2006 IBM Corporation and others. |
| 3 | * All rights reserved. This program and the accompanying materials |
| 4 | * are made available under the terms of the Eclipse Public License v1.0 |
| 5 | * which accompanies this distribution, and is available at |
| 6 | * http://www.eclipse.org/legal/epl-v10.html |
| 7 | * |
| 8 | * Contributors: |
| 9 | * IBM Corporation - initial API and implementation |
| 10 | *******************************************************************************/ |
| 11 | |
| 12 | package org.eclipse.jface.commands; |
| 13 | |
| 14 | import org.eclipse.core.commands.State; |
| 15 | import org.eclipse.jface.preference.IPreferenceStore; |
| 16 | |
| 17 | /** |
| 18 | * <p> |
| 19 | * This is a state that can be made persistent. A state is persisted to a |
| 20 | * preference store. |
| 21 | * </p> |
| 22 | * <p> |
| 23 | * Clients may extend this class. |
| 24 | * </p> |
| 25 | * |
| 26 | * @since 3.2 |
| 27 | */ |
| 28 | public abstract class PersistentState extends State { |
| 29 | |
| 30 | /** |
| 31 | * Whether this state should be persisted. |
| 32 | */ |
| 33 | private boolean persisted; |
| 34 | |
| 35 | /** |
| 36 | * Loads this state from the preference store, given the location at which |
| 37 | * to look. This method must be symmetric with a call to |
| 38 | * {@link #save(IPreferenceStore, String)}. |
| 39 | * |
| 40 | * @param store |
| 41 | * The store from which to read; must not be <code>null</code>. |
| 42 | * @param preferenceKey |
| 43 | * The key at which the state is stored; must not be |
| 44 | * <code>null</code>. |
| 45 | */ |
| 46 | public abstract void load(final IPreferenceStore store, |
| 47 | final String preferenceKey); |
| 48 | |
| 49 | /** |
| 50 | * Saves this state to the preference store, given the location at which to |
| 51 | * write. This method must be symmetric with a call to |
| 52 | * {@link #load(IPreferenceStore, String)}. |
| 53 | * |
| 54 | * @param store |
| 55 | * The store to which the state should be written; must not be |
| 56 | * <code>null</code>. |
| 57 | * @param preferenceKey |
| 58 | * The key at which the state should be stored; must not be |
| 59 | * <code>null</code>. |
| 60 | */ |
| 61 | public abstract void save(final IPreferenceStore store, |
| 62 | final String preferenceKey); |
| 63 | |
| 64 | /** |
| 65 | * Sets whether this state should be persisted. |
| 66 | * |
| 67 | * @param persisted |
| 68 | * Whether this state should be persisted. |
| 69 | */ |
| 70 | public void setShouldPersist(final boolean persisted) { |
| 71 | this.persisted = persisted; |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Whether this state should be persisted. Subclasses should check this |
| 76 | * method before loading or saving. |
| 77 | * |
| 78 | * @return <code>true</code> if this state should be persisted; |
| 79 | * <code>false</code> otherwise. |
| 80 | */ |
| 81 | public boolean shouldPersist() { |
| 82 | return persisted; |
| 83 | } |
| 84 | } |