| /* MemoryBasedPreferences - A Preference node which holds all entries in memory |
| Copyright (C) 2001 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package gnu.java.util.prefs; |
| |
| import java.util.HashMap; |
| |
| import java.util.prefs.*; |
| |
| /** |
| * A Preference node which holds all entries in memory |
| * |
| * @author Mark Wielaard (mark@klomp.org) |
| */ |
| public class MemoryBasedPreferences extends AbstractPreferences { |
| |
| /** True if this is a preference node in the user tree, false otherwise. */ |
| private final boolean isUser; |
| |
| /** Contains all the preference entries of this node. */ |
| private HashMap entries = new HashMap(); |
| |
| /** |
| * Creates a new preferences node with the given name and parent. |
| * When isUser is true it will be user node otherwise it will be a system |
| * node. It will always set the <code>newNode</code> field to true |
| * since there is no real backing store, so all nodes are new. |
| */ |
| public MemoryBasedPreferences(MemoryBasedPreferences parent, |
| String name, |
| boolean isUser) { |
| super(parent, name); |
| this.isUser = isUser; |
| |
| // Since we do not have a real backing store all nodes are new |
| newNode = true; |
| } |
| |
| /** |
| * Returns true if this node was created as a user node. |
| */ |
| public boolean isUserNode() { |
| return isUser; |
| } |
| |
| /** |
| * Returns an empty array since all children names are always already |
| * chached. |
| */ |
| protected String[] childrenNamesSpi() throws BackingStoreException { |
| return new String[0]; |
| } |
| |
| /** |
| * Returns a new node with the given name with as parent this node and |
| * with the <code>isUser</code> flag set to the same value as this node. |
| */ |
| protected AbstractPreferences childSpi(String childName) { |
| return new MemoryBasedPreferences(this, childName, isUser); |
| } |
| |
| /** |
| * Returns a (possibly empty) array of keys of the preferences entries of |
| * this node. |
| */ |
| protected String[] keysSpi() throws BackingStoreException { |
| return (String[]) entries.keySet().toArray(new String[entries.size()]); |
| } |
| |
| /** |
| * Returns the associated value from this nodes preferences entries or |
| * null when the key has not been set. |
| */ |
| protected String getSpi(String key) { |
| return (String) entries.get(key); |
| } |
| |
| /** |
| * Sets the value for the given key. |
| */ |
| protected void putSpi(String key, String value) { |
| entries.put(key, value); |
| } |
| |
| /** |
| * Removes the entry with the given key. |
| */ |
| protected void removeSpi(String key) { |
| entries.remove(key); |
| } |
| |
| /** |
| * Does nothing since we do not have any backing store. |
| */ |
| protected void flushSpi() { |
| } |
| |
| /** |
| * Does nothing since we do not have any backing store. |
| */ |
| protected void syncSpi() { |
| } |
| |
| /** |
| * Just removes the entries map of this node. |
| */ |
| protected void removeNodeSpi() { |
| entries = null; |
| } |
| } |