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jlechner |
/* AbstractPreferences -- Partial implementation of a Preference node
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Copyright (C) 2001, 2003, 2004 Free Software Foundation, Inc.
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING. If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA.
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library. Thus, the terms and
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conditions of the GNU General Public License cover the whole
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combination.
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module. An independent module is a module which is not derived from
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or based on this library. If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so. If you do not wish to do so, delete this
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exception statement from your version. */
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package java.util.prefs;
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import gnu.java.util.prefs.NodeWriter;
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import java.io.ByteArrayOutputStream;
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import java.io.IOException;
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import java.io.OutputStream;
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import java.util.HashMap;
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import java.util.Iterator;
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import java.util.TreeSet;
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/**
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* Partial implementation of a Preference node.
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*
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* @since 1.4
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* @author Mark Wielaard (mark@klomp.org)
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*/
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public abstract class AbstractPreferences extends Preferences {
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// protected fields
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/**
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* Object used to lock this preference node. Any thread only locks nodes
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* downwards when it has the lock on the current node. No method should
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* synchronize on the lock of any of its parent nodes while holding the
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* lock on the current node.
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*/
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protected final Object lock = new Object();
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/**
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* Set to true in the contructor if the node did not exist in the backing
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* store when this preference node object was created. Should be set in
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* the contructor of a subclass. Defaults to false. Used to fire node
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* changed events.
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*/
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protected boolean newNode = false;
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// private fields
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/**
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* The parent preferences node or null when this is the root node.
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*/
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private final AbstractPreferences parent;
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/**
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* The name of this node.
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* Only when this is a root node (parent == null) the name is empty.
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* It has a maximum of 80 characters and cannot contain any '/' characters.
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*/
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private final String name;
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/** True when this node has been remove, false otherwise. */
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private boolean removed = false;
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/**
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* Holds all the child names and nodes of this node that have been
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* accessed by earlier <code>getChild()</code> or <code>childSpi()</code>
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* invocations and that have not been removed.
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*/
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private HashMap childCache = new HashMap();
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// constructor
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/**
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* Creates a new AbstractPreferences node with the given parent and name.
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*
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* @param parent the parent of this node or null when this is the root node
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* @param name the name of this node, can not be null, only 80 characters
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* maximum, must be empty when parent is null and cannot
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* contain any '/' characters
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* @exception IllegalArgumentException when name is null, greater then 80
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* characters, not the empty string but parent is null or
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* contains a '/' character
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*/
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protected AbstractPreferences(AbstractPreferences parent, String name) {
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if ( (name == null) // name should be given
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|| (name.length() > MAX_NAME_LENGTH) // 80 characters max
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|| (parent == null && name.length() != 0) // root has no name
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|| (parent != null && name.length() == 0) // all other nodes do
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|| (name.indexOf('/') != -1)) // must not contain '/'
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throw new IllegalArgumentException("Illegal name argument '"
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+ name
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+ "' (parent is "
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+ (parent == null ? "" : "not ")
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+ "null)");
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this.parent = parent;
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this.name = name;
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}
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// identification methods
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/**
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* Returns the absolute path name of this preference node.
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* The absolute path name of a node is the path name of its parent node
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* plus a '/' plus its own name. If the node is the root node and has no
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* parent then its path name is "" and its absolute path name is "/".
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*/
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public String absolutePath() {
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if (parent == null)
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return "/";
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else
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return parent.path() + '/' + name;
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}
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/**
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* Private helper method for absolutePath. Returns the empty string for a
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* root node and otherwise the parentPath of its parent plus a '/'.
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*/
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private String path() {
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if (parent == null)
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return "";
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else
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return parent.path() + '/' + name;
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}
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/**
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* Returns true if this node comes from the user preferences tree, false
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* if it comes from the system preferences tree.
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*/
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public boolean isUserNode() {
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AbstractPreferences root = this;
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while (root.parent != null)
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root = root.parent;
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return root == Preferences.userRoot();
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}
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/**
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* Returns the name of this preferences node. The name of the node cannot
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* be null, can be mostly 80 characters and cannot contain any '/'
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* characters. The root node has as name "".
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*/
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public String name() {
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return name;
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}
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/**
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* Returns the String given by
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* <code>
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* (isUserNode() ? "User":"System") + " Preference Node: " + absolutePath()
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* </code>
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*/
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public String toString() {
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return (isUserNode() ? "User":"System")
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+ " Preference Node: "
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+ absolutePath();
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}
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/**
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* Returns all known unremoved children of this node.
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*
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* @return All known unremoved children of this node
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*/
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protected final AbstractPreferences[] cachedChildren()
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{
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return (AbstractPreferences[]) childCache.values().toArray();
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}
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/**
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* Returns all the direct sub nodes of this preferences node.
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* Needs access to the backing store to give a meaningfull answer.
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* <p>
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* This implementation locks this node, checks if the node has not yet
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* been removed and throws an <code>IllegalStateException</code> when it
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* has been. Then it creates a new <code>TreeSet</code> and adds any
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* already cached child nodes names. To get any uncached names it calls
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* <code>childrenNamesSpi()</code> and adds the result to the set. Finally
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* it calls <code>toArray()</code> on the created set. When the call to
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* <code>childrenNamesSpi</code> thows an <code>BackingStoreException</code>
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* this method will not catch that exception but propagate the exception
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* to the caller.
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*
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* @exception BackingStoreException when the backing store cannot be
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* reached
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* @exception IllegalStateException when this node has been removed
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*/
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public String[] childrenNames() throws BackingStoreException {
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synchronized(lock) {
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if (isRemoved())
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throw new IllegalStateException("Node removed");
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TreeSet childrenNames = new TreeSet();
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// First get all cached node names
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childrenNames.addAll(childCache.keySet());
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// Then add any others
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String names[] = childrenNamesSpi();
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for (int i = 0; i < names.length; i++) {
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childrenNames.add(names[i]);
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}
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// And return the array of names
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String[] children = new String[childrenNames.size()];
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childrenNames.toArray(children);
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return children;
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}
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}
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/**
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* Returns a sub node of this preferences node if the given path is
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* relative (does not start with a '/') or a sub node of the root
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* if the path is absolute (does start with a '/').
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* <p>
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* This method first locks this node and checks if the node has not been
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* removed, if it has been removed it throws an exception. Then if the
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* path is relative (does not start with a '/') it checks if the path is
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* legal (does not end with a '/' and has no consecutive '/' characters).
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* Then it recursively gets a name from the path, gets the child node
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* from the child-cache of this node or calls the <code>childSpi()</code>
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* method to create a new child sub node. This is done recursively on the
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* newly created sub node with the rest of the path till the path is empty.
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* If the path is absolute (starts with a '/') the lock on this node is
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* droped and this method is called on the root of the preferences tree
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* with as argument the complete path minus the first '/'.
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*
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* @exception IllegalStateException if this node has been removed
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* @exception IllegalArgumentException if the path contains two or more
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* consecutive '/' characters, ends with a '/' charactor and is not the
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* string "/" (indicating the root node) or any name on the path is more
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* then 80 characters long
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*/
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public Preferences node(String path) {
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synchronized(lock) {
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if (isRemoved())
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throw new IllegalStateException("Node removed");
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// Is it a relative path?
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if (!path.startsWith("/")) {
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// Check if it is a valid path
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if (path.indexOf("//") != -1 || path.endsWith("/"))
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throw new IllegalArgumentException(path);
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return getNode(path);
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}
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}
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// path started with a '/' so it is absolute
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// we drop the lock and start from the root (omitting the first '/')
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Preferences root = isUserNode() ? userRoot() : systemRoot();
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return root.node(path.substring(1));
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}
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/**
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* Private helper method for <code>node()</code>. Called with this node
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* locked. Returns this node when path is the empty string, if it is not
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* empty the next node name is taken from the path (all chars till the
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* next '/' or end of path string) and the node is either taken from the
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* child-cache of this node or the <code>childSpi()</code> method is called
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* on this node with the name as argument. Then this method is called
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* recursively on the just constructed child node with the rest of the
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* path.
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*
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* @param path should not end with a '/' character and should not contain
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* consecutive '/' characters
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* @exception IllegalArgumentException if path begins with a name that is
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* larger then 80 characters.
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*/
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private Preferences getNode(String path) {
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// if mark is dom then goto end
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// Empty String "" indicates this node
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if (path.length() == 0)
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return this;
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// Calculate child name and rest of path
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String childName;
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String childPath;
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int nextSlash = path.indexOf('/');
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if (nextSlash == -1) {
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childName = path;
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childPath = "";
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} else {
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childName = path.substring(0, nextSlash);
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childPath = path.substring(nextSlash+1);
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}
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// Get the child node
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AbstractPreferences child;
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child = (AbstractPreferences)childCache.get(childName);
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if (child == null) {
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if (childName.length() > MAX_NAME_LENGTH)
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throw new IllegalArgumentException(childName);
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// Not in childCache yet so create a new sub node
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child = childSpi(childName);
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// XXX - check if node is new
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childCache.put(childName, child);
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}
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// Lock the child and go down
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synchronized(child.lock) {
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return child.getNode(childPath);
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}
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}
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/**
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* Returns true if the node that the path points to exists in memory or
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* in the backing store. Otherwise it returns false or an exception is
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* thrown. When this node is removed the only valid parameter is the
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* empty string (indicating this node), the return value in that case
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* will be false.
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*
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* @exception BackingStoreException when the backing store cannot be
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* reached
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* @exception IllegalStateException if this node has been removed
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* and the path is not the empty string (indicating this node)
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* @exception IllegalArgumentException if the path contains two or more
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* consecutive '/' characters, ends with a '/' charactor and is not the
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* string "/" (indicating the root node) or any name on the path is more
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* then 80 characters long
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*/
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public boolean nodeExists(String path) throws BackingStoreException {
|
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synchronized(lock) {
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if (isRemoved() && path.length() != 0)
|
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throw new IllegalStateException("Node removed");
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// Is it a relative path?
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if (!path.startsWith("/")) {
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// Check if it is a valid path
|
363 |
|
|
if (path.indexOf("//") != -1 || path.endsWith("/"))
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throw new IllegalArgumentException(path);
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365 |
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|
|
366 |
|
|
return existsNode(path);
|
367 |
|
|
}
|
368 |
|
|
}
|
369 |
|
|
|
370 |
|
|
// path started with a '/' so it is absolute
|
371 |
|
|
// we drop the lock and start from the root (omitting the first '/')
|
372 |
|
|
Preferences root = isUserNode() ? userRoot() : systemRoot();
|
373 |
|
|
return root.nodeExists(path.substring(1));
|
374 |
|
|
|
375 |
|
|
}
|
376 |
|
|
|
377 |
|
|
private boolean existsNode(String path) throws BackingStoreException {
|
378 |
|
|
|
379 |
|
|
// Empty String "" indicates this node
|
380 |
|
|
if (path.length() == 0)
|
381 |
|
|
return(!isRemoved());
|
382 |
|
|
|
383 |
|
|
// Calculate child name and rest of path
|
384 |
|
|
String childName;
|
385 |
|
|
String childPath;
|
386 |
|
|
int nextSlash = path.indexOf('/');
|
387 |
|
|
if (nextSlash == -1) {
|
388 |
|
|
childName = path;
|
389 |
|
|
childPath = "";
|
390 |
|
|
} else {
|
391 |
|
|
childName = path.substring(0, nextSlash);
|
392 |
|
|
childPath = path.substring(nextSlash+1);
|
393 |
|
|
}
|
394 |
|
|
|
395 |
|
|
// Get the child node
|
396 |
|
|
AbstractPreferences child;
|
397 |
|
|
child = (AbstractPreferences)childCache.get(childName);
|
398 |
|
|
if (child == null) {
|
399 |
|
|
|
400 |
|
|
if (childName.length() > MAX_NAME_LENGTH)
|
401 |
|
|
throw new IllegalArgumentException(childName);
|
402 |
|
|
|
403 |
|
|
// Not in childCache yet so create a new sub node
|
404 |
|
|
child = getChild(childName);
|
405 |
|
|
|
406 |
|
|
if (child == null)
|
407 |
|
|
return false;
|
408 |
|
|
|
409 |
|
|
childCache.put(childName, child);
|
410 |
|
|
}
|
411 |
|
|
|
412 |
|
|
// Lock the child and go down
|
413 |
|
|
synchronized(child.lock) {
|
414 |
|
|
return child.existsNode(childPath);
|
415 |
|
|
}
|
416 |
|
|
}
|
417 |
|
|
|
418 |
|
|
/**
|
419 |
|
|
* Returns the child sub node if it exists in the backing store or null
|
420 |
|
|
* if it does not exist. Called (indirectly) by <code>nodeExists()</code>
|
421 |
|
|
* when a child node name can not be found in the cache.
|
422 |
|
|
* <p>
|
423 |
|
|
* Gets the lock on this node, calls <code>childrenNamesSpi()</code> to
|
424 |
|
|
* get an array of all (possibly uncached) children and compares the
|
425 |
|
|
* given name with the names in the array. If the name is found in the
|
426 |
|
|
* array <code>childSpi()</code> is called to get an instance, otherwise
|
427 |
|
|
* null is returned.
|
428 |
|
|
*
|
429 |
|
|
* @exception BackingStoreException when the backing store cannot be
|
430 |
|
|
* reached
|
431 |
|
|
*/
|
432 |
|
|
protected AbstractPreferences getChild(String name)
|
433 |
|
|
throws BackingStoreException
|
434 |
|
|
{
|
435 |
|
|
synchronized(lock) {
|
436 |
|
|
// Get all the names (not yet in the cache)
|
437 |
|
|
String[] names = childrenNamesSpi();
|
438 |
|
|
for (int i=0; i < names.length; i++)
|
439 |
|
|
if (name.equals(names[i]))
|
440 |
|
|
return childSpi(name);
|
441 |
|
|
|
442 |
|
|
// No child with that name found
|
443 |
|
|
return null;
|
444 |
|
|
}
|
445 |
|
|
}
|
446 |
|
|
|
447 |
|
|
/**
|
448 |
|
|
* Returns true if this node has been removed with the
|
449 |
|
|
* <code>removeNode()</code> method, false otherwise.
|
450 |
|
|
* <p>
|
451 |
|
|
* Gets the lock on this node and then returns a boolean field set by
|
452 |
|
|
* <code>removeNode</code> methods.
|
453 |
|
|
*/
|
454 |
|
|
protected boolean isRemoved() {
|
455 |
|
|
synchronized(lock) {
|
456 |
|
|
return removed;
|
457 |
|
|
}
|
458 |
|
|
}
|
459 |
|
|
|
460 |
|
|
/**
|
461 |
|
|
* Returns the parent preferences node of this node or null if this is
|
462 |
|
|
* the root of the preferences tree.
|
463 |
|
|
* <p>
|
464 |
|
|
* Gets the lock on this node, checks that the node has not been removed
|
465 |
|
|
* and returns the parent given to the constructor.
|
466 |
|
|
*
|
467 |
|
|
* @exception IllegalStateException if this node has been removed
|
468 |
|
|
*/
|
469 |
|
|
public Preferences parent() {
|
470 |
|
|
synchronized(lock) {
|
471 |
|
|
if (isRemoved())
|
472 |
|
|
throw new IllegalStateException("Node removed");
|
473 |
|
|
|
474 |
|
|
return parent;
|
475 |
|
|
}
|
476 |
|
|
}
|
477 |
|
|
|
478 |
|
|
// export methods
|
479 |
|
|
|
480 |
|
|
/**
|
481 |
|
|
* XXX
|
482 |
|
|
*/
|
483 |
|
|
public void exportNode(OutputStream os)
|
484 |
|
|
throws BackingStoreException,
|
485 |
|
|
IOException
|
486 |
|
|
{
|
487 |
|
|
NodeWriter nodeWriter = new NodeWriter(this, os);
|
488 |
|
|
nodeWriter.writePrefs();
|
489 |
|
|
}
|
490 |
|
|
|
491 |
|
|
/**
|
492 |
|
|
* XXX
|
493 |
|
|
*/
|
494 |
|
|
public void exportSubtree(OutputStream os)
|
495 |
|
|
throws BackingStoreException,
|
496 |
|
|
IOException
|
497 |
|
|
{
|
498 |
|
|
NodeWriter nodeWriter = new NodeWriter(this, os);
|
499 |
|
|
nodeWriter.writePrefsTree();
|
500 |
|
|
}
|
501 |
|
|
|
502 |
|
|
// preference entry manipulation methods
|
503 |
|
|
|
504 |
|
|
/**
|
505 |
|
|
* Returns an (possibly empty) array with all the keys of the preference
|
506 |
|
|
* entries of this node.
|
507 |
|
|
* <p>
|
508 |
|
|
* This method locks this node and checks if the node has not been
|
509 |
|
|
* removed, if it has been removed it throws an exception, then it returns
|
510 |
|
|
* the result of calling <code>keysSpi()</code>.
|
511 |
|
|
*
|
512 |
|
|
* @exception BackingStoreException when the backing store cannot be
|
513 |
|
|
* reached
|
514 |
|
|
* @exception IllegalStateException if this node has been removed
|
515 |
|
|
*/
|
516 |
|
|
public String[] keys() throws BackingStoreException {
|
517 |
|
|
synchronized(lock) {
|
518 |
|
|
if (isRemoved())
|
519 |
|
|
throw new IllegalStateException("Node removed");
|
520 |
|
|
|
521 |
|
|
return keysSpi();
|
522 |
|
|
}
|
523 |
|
|
}
|
524 |
|
|
|
525 |
|
|
|
526 |
|
|
/**
|
527 |
|
|
* Returns the value associated with the key in this preferences node. If
|
528 |
|
|
* the default value of the key cannot be found in the preferences node
|
529 |
|
|
* entries or something goes wrong with the backing store the supplied
|
530 |
|
|
* default value is returned.
|
531 |
|
|
* <p>
|
532 |
|
|
* Checks that key is not null and not larger then 80 characters,
|
533 |
|
|
* locks this node, and checks that the node has not been removed.
|
534 |
|
|
* Then it calls <code>keySpi()</code> and returns
|
535 |
|
|
* the result of that method or the given default value if it returned
|
536 |
|
|
* null or throwed an exception.
|
537 |
|
|
*
|
538 |
|
|
* @exception IllegalArgumentException if key is larger then 80 characters
|
539 |
|
|
* @exception IllegalStateException if this node has been removed
|
540 |
|
|
* @exception NullPointerException if key is null
|
541 |
|
|
*/
|
542 |
|
|
public String get(String key, String defaultVal) {
|
543 |
|
|
if (key.length() > MAX_KEY_LENGTH)
|
544 |
|
|
throw new IllegalArgumentException(key);
|
545 |
|
|
|
546 |
|
|
synchronized(lock) {
|
547 |
|
|
if (isRemoved())
|
548 |
|
|
throw new IllegalStateException("Node removed");
|
549 |
|
|
|
550 |
|
|
String value;
|
551 |
|
|
try {
|
552 |
|
|
value = getSpi(key);
|
553 |
|
|
} catch (ThreadDeath death) {
|
554 |
|
|
throw death;
|
555 |
|
|
} catch (Throwable t) {
|
556 |
|
|
value = null;
|
557 |
|
|
}
|
558 |
|
|
|
559 |
|
|
if (value != null) {
|
560 |
|
|
return value;
|
561 |
|
|
} else {
|
562 |
|
|
return defaultVal;
|
563 |
|
|
}
|
564 |
|
|
}
|
565 |
|
|
}
|
566 |
|
|
|
567 |
|
|
/**
|
568 |
|
|
* Convenience method for getting the given entry as a boolean.
|
569 |
|
|
* When the string representation of the requested entry is either
|
570 |
|
|
* "true" or "false" (ignoring case) then that value is returned,
|
571 |
|
|
* otherwise the given default boolean value is returned.
|
572 |
|
|
*
|
573 |
|
|
* @exception IllegalArgumentException if key is larger then 80 characters
|
574 |
|
|
* @exception IllegalStateException if this node has been removed
|
575 |
|
|
* @exception NullPointerException if key is null
|
576 |
|
|
*/
|
577 |
|
|
public boolean getBoolean(String key, boolean defaultVal) {
|
578 |
|
|
String value = get(key, null);
|
579 |
|
|
|
580 |
|
|
if ("true".equalsIgnoreCase(value))
|
581 |
|
|
return true;
|
582 |
|
|
|
583 |
|
|
if ("false".equalsIgnoreCase(value))
|
584 |
|
|
return false;
|
585 |
|
|
|
586 |
|
|
return defaultVal;
|
587 |
|
|
}
|
588 |
|
|
|
589 |
|
|
/**
|
590 |
|
|
* Convenience method for getting the given entry as a byte array.
|
591 |
|
|
* When the string representation of the requested entry is a valid
|
592 |
|
|
* Base64 encoded string (without any other characters, such as newlines)
|
593 |
|
|
* then the decoded Base64 string is returned as byte array,
|
594 |
|
|
* otherwise the given default byte array value is returned.
|
595 |
|
|
*
|
596 |
|
|
* @exception IllegalArgumentException if key is larger then 80 characters
|
597 |
|
|
* @exception IllegalStateException if this node has been removed
|
598 |
|
|
* @exception NullPointerException if key is null
|
599 |
|
|
*/
|
600 |
|
|
public byte[] getByteArray(String key, byte[] defaultVal) {
|
601 |
|
|
String value = get(key, null);
|
602 |
|
|
|
603 |
|
|
byte[] b = null;
|
604 |
|
|
if (value != null) {
|
605 |
|
|
b = decode64(value);
|
606 |
|
|
}
|
607 |
|
|
|
608 |
|
|
if (b != null)
|
609 |
|
|
return b;
|
610 |
|
|
else
|
611 |
|
|
return defaultVal;
|
612 |
|
|
}
|
613 |
|
|
|
614 |
|
|
/**
|
615 |
|
|
* Helper method for decoding a Base64 string as an byte array.
|
616 |
|
|
* Returns null on encoding error. This method does not allow any other
|
617 |
|
|
* characters present in the string then the 65 special base64 chars.
|
618 |
|
|
*/
|
619 |
|
|
private static byte[] decode64(String s) {
|
620 |
|
|
ByteArrayOutputStream bs = new ByteArrayOutputStream((s.length()/4)*3);
|
621 |
|
|
char[] c = new char[s.length()];
|
622 |
|
|
s.getChars(0, s.length(), c, 0);
|
623 |
|
|
|
624 |
|
|
// Convert from base64 chars
|
625 |
|
|
int endchar = -1;
|
626 |
|
|
for(int j = 0; j < c.length && endchar == -1; j++) {
|
627 |
|
|
if (c[j] >= 'A' && c[j] <= 'Z') {
|
628 |
|
|
c[j] -= 'A';
|
629 |
|
|
} else if (c[j] >= 'a' && c[j] <= 'z') {
|
630 |
|
|
c[j] = (char) (c[j] + 26 - 'a');
|
631 |
|
|
} else if (c[j] >= '0' && c[j] <= '9') {
|
632 |
|
|
c[j] = (char) (c[j] + 52 - '0');
|
633 |
|
|
} else if (c[j] == '+') {
|
634 |
|
|
c[j] = 62;
|
635 |
|
|
} else if (c[j] == '/') {
|
636 |
|
|
c[j] = 63;
|
637 |
|
|
} else if (c[j] == '=') {
|
638 |
|
|
endchar = j;
|
639 |
|
|
} else {
|
640 |
|
|
return null; // encoding exception
|
641 |
|
|
}
|
642 |
|
|
}
|
643 |
|
|
|
644 |
|
|
int remaining = endchar == -1 ? c.length : endchar;
|
645 |
|
|
int i = 0;
|
646 |
|
|
while (remaining > 0) {
|
647 |
|
|
// Four input chars (6 bits) are decoded as three bytes as
|
648 |
|
|
// 000000 001111 111122 222222
|
649 |
|
|
|
650 |
|
|
byte b0 = (byte) (c[i] << 2);
|
651 |
|
|
if (remaining >= 2) {
|
652 |
|
|
b0 += (c[i+1] & 0x30) >> 4;
|
653 |
|
|
}
|
654 |
|
|
bs.write(b0);
|
655 |
|
|
|
656 |
|
|
if (remaining >= 3) {
|
657 |
|
|
byte b1 = (byte) ((c[i+1] & 0x0F) << 4);
|
658 |
|
|
b1 += (byte) ((c[i+2] & 0x3C) >> 2);
|
659 |
|
|
bs.write(b1);
|
660 |
|
|
}
|
661 |
|
|
|
662 |
|
|
if (remaining >= 4) {
|
663 |
|
|
byte b2 = (byte) ((c[i+2] & 0x03) << 6);
|
664 |
|
|
b2 += c[i+3];
|
665 |
|
|
bs.write(b2);
|
666 |
|
|
}
|
667 |
|
|
|
668 |
|
|
i += 4;
|
669 |
|
|
remaining -= 4;
|
670 |
|
|
}
|
671 |
|
|
|
672 |
|
|
return bs.toByteArray();
|
673 |
|
|
}
|
674 |
|
|
|
675 |
|
|
/**
|
676 |
|
|
* Convenience method for getting the given entry as a double.
|
677 |
|
|
* When the string representation of the requested entry can be decoded
|
678 |
|
|
* with <code>Double.parseDouble()</code> then that double is returned,
|
679 |
|
|
* otherwise the given default double value is returned.
|
680 |
|
|
*
|
681 |
|
|
* @exception IllegalArgumentException if key is larger then 80 characters
|
682 |
|
|
* @exception IllegalStateException if this node has been removed
|
683 |
|
|
* @exception NullPointerException if key is null
|
684 |
|
|
*/
|
685 |
|
|
public double getDouble(String key, double defaultVal) {
|
686 |
|
|
String value = get(key, null);
|
687 |
|
|
|
688 |
|
|
if (value != null) {
|
689 |
|
|
try {
|
690 |
|
|
return Double.parseDouble(value);
|
691 |
|
|
} catch (NumberFormatException nfe) { /* ignore */ }
|
692 |
|
|
}
|
693 |
|
|
|
694 |
|
|
return defaultVal;
|
695 |
|
|
}
|
696 |
|
|
|
697 |
|
|
/**
|
698 |
|
|
* Convenience method for getting the given entry as a float.
|
699 |
|
|
* When the string representation of the requested entry can be decoded
|
700 |
|
|
* with <code>Float.parseFloat()</code> then that float is returned,
|
701 |
|
|
* otherwise the given default float value is returned.
|
702 |
|
|
*
|
703 |
|
|
* @exception IllegalArgumentException if key is larger then 80 characters
|
704 |
|
|
* @exception IllegalStateException if this node has been removed
|
705 |
|
|
* @exception NullPointerException if key is null
|
706 |
|
|
*/
|
707 |
|
|
public float getFloat(String key, float defaultVal) {
|
708 |
|
|
String value = get(key, null);
|
709 |
|
|
|
710 |
|
|
if (value != null) {
|
711 |
|
|
try {
|
712 |
|
|
return Float.parseFloat(value);
|
713 |
|
|
} catch (NumberFormatException nfe) { /* ignore */ }
|
714 |
|
|
}
|
715 |
|
|
|
716 |
|
|
return defaultVal;
|
717 |
|
|
}
|
718 |
|
|
|
719 |
|
|
/**
|
720 |
|
|
* Convenience method for getting the given entry as an integer.
|
721 |
|
|
* When the string representation of the requested entry can be decoded
|
722 |
|
|
* with <code>Integer.parseInt()</code> then that integer is returned,
|
723 |
|
|
* otherwise the given default integer value is returned.
|
724 |
|
|
*
|
725 |
|
|
* @exception IllegalArgumentException if key is larger then 80 characters
|
726 |
|
|
* @exception IllegalStateException if this node has been removed
|
727 |
|
|
* @exception NullPointerException if key is null
|
728 |
|
|
*/
|
729 |
|
|
public int getInt(String key, int defaultVal) {
|
730 |
|
|
String value = get(key, null);
|
731 |
|
|
|
732 |
|
|
if (value != null) {
|
733 |
|
|
try {
|
734 |
|
|
return Integer.parseInt(value);
|
735 |
|
|
} catch (NumberFormatException nfe) { /* ignore */ }
|
736 |
|
|
}
|
737 |
|
|
|
738 |
|
|
return defaultVal;
|
739 |
|
|
}
|
740 |
|
|
|
741 |
|
|
/**
|
742 |
|
|
* Convenience method for getting the given entry as a long.
|
743 |
|
|
* When the string representation of the requested entry can be decoded
|
744 |
|
|
* with <code>Long.parseLong()</code> then that long is returned,
|
745 |
|
|
* otherwise the given default long value is returned.
|
746 |
|
|
*
|
747 |
|
|
* @exception IllegalArgumentException if key is larger then 80 characters
|
748 |
|
|
* @exception IllegalStateException if this node has been removed
|
749 |
|
|
* @exception NullPointerException if key is null
|
750 |
|
|
*/
|
751 |
|
|
public long getLong(String key, long defaultVal) {
|
752 |
|
|
String value = get(key, null);
|
753 |
|
|
|
754 |
|
|
if (value != null) {
|
755 |
|
|
try {
|
756 |
|
|
return Long.parseLong(value);
|
757 |
|
|
} catch (NumberFormatException nfe) { /* ignore */ }
|
758 |
|
|
}
|
759 |
|
|
|
760 |
|
|
return defaultVal;
|
761 |
|
|
}
|
762 |
|
|
|
763 |
|
|
/**
|
764 |
|
|
* Sets the value of the given preferences entry for this node.
|
765 |
|
|
* Key and value cannot be null, the key cannot exceed 80 characters
|
766 |
|
|
* and the value cannot exceed 8192 characters.
|
767 |
|
|
* <p>
|
768 |
|
|
* The result will be immediatly visible in this VM, but may not be
|
769 |
|
|
* immediatly written to the backing store.
|
770 |
|
|
* <p>
|
771 |
|
|
* Checks that key and value are valid, locks this node, and checks that
|
772 |
|
|
* the node has not been removed. Then it calls <code>putSpi()</code>.
|
773 |
|
|
*
|
774 |
|
|
* @exception NullPointerException if either key or value are null
|
775 |
|
|
* @exception IllegalArgumentException if either key or value are to large
|
776 |
|
|
* @exception IllegalStateException when this node has been removed
|
777 |
|
|
*/
|
778 |
|
|
public void put(String key, String value) {
|
779 |
|
|
if (key.length() > MAX_KEY_LENGTH
|
780 |
|
|
|| value.length() > MAX_VALUE_LENGTH)
|
781 |
|
|
throw new IllegalArgumentException("key ("
|
782 |
|
|
+ key.length() + ")"
|
783 |
|
|
+ " or value ("
|
784 |
|
|
+ value.length() + ")"
|
785 |
|
|
+ " to large");
|
786 |
|
|
synchronized(lock) {
|
787 |
|
|
if (isRemoved())
|
788 |
|
|
throw new IllegalStateException("Node removed");
|
789 |
|
|
|
790 |
|
|
putSpi(key, value);
|
791 |
|
|
|
792 |
|
|
// XXX - fire events
|
793 |
|
|
}
|
794 |
|
|
|
795 |
|
|
}
|
796 |
|
|
|
797 |
|
|
/**
|
798 |
|
|
* Convenience method for setting the given entry as a boolean.
|
799 |
|
|
* The boolean is converted with <code>Boolean.toString(value)</code>
|
800 |
|
|
* and then stored in the preference entry as that string.
|
801 |
|
|
*
|
802 |
|
|
* @exception NullPointerException if key is null
|
803 |
|
|
* @exception IllegalArgumentException if the key length is to large
|
804 |
|
|
* @exception IllegalStateException when this node has been removed
|
805 |
|
|
*/
|
806 |
|
|
public void putBoolean(String key, boolean value) {
|
807 |
|
|
put(key, String.valueOf(value));
|
808 |
|
|
// XXX - Use when using 1.4 compatible Boolean
|
809 |
|
|
// put(key, Boolean.toString(value));
|
810 |
|
|
}
|
811 |
|
|
|
812 |
|
|
/**
|
813 |
|
|
* Convenience method for setting the given entry as an array of bytes.
|
814 |
|
|
* The byte array is converted to a Base64 encoded string
|
815 |
|
|
* and then stored in the preference entry as that string.
|
816 |
|
|
* <p>
|
817 |
|
|
* Note that a byte array encoded as a Base64 string will be about 1.3
|
818 |
|
|
* times larger then the original length of the byte array, which means
|
819 |
|
|
* that the byte array may not be larger about 6 KB.
|
820 |
|
|
*
|
821 |
|
|
* @exception NullPointerException if either key or value are null
|
822 |
|
|
* @exception IllegalArgumentException if either key or value are to large
|
823 |
|
|
* @exception IllegalStateException when this node has been removed
|
824 |
|
|
*/
|
825 |
|
|
public void putByteArray(String key, byte[] value) {
|
826 |
|
|
put(key, encode64(value));
|
827 |
|
|
}
|
828 |
|
|
|
829 |
|
|
/**
|
830 |
|
|
* Helper method for encoding an array of bytes as a Base64 String.
|
831 |
|
|
*/
|
832 |
|
|
private static String encode64(byte[] b) {
|
833 |
|
|
StringBuffer sb = new StringBuffer((b.length/3)*4);
|
834 |
|
|
|
835 |
|
|
int i = 0;
|
836 |
|
|
int remaining = b.length;
|
837 |
|
|
char c[] = new char[4];
|
838 |
|
|
while (remaining > 0) {
|
839 |
|
|
// Three input bytes are encoded as four chars (6 bits) as
|
840 |
|
|
// 00000011 11112222 22333333
|
841 |
|
|
|
842 |
|
|
c[0] = (char) ((b[i] & 0xFC) >> 2);
|
843 |
|
|
c[1] = (char) ((b[i] & 0x03) << 4);
|
844 |
|
|
if (remaining >= 2) {
|
845 |
|
|
c[1] += (char) ((b[i+1] & 0xF0) >> 4);
|
846 |
|
|
c[2] = (char) ((b[i+1] & 0x0F) << 2);
|
847 |
|
|
if (remaining >= 3) {
|
848 |
|
|
c[2] += (char) ((b[i+2] & 0xC0) >> 6);
|
849 |
|
|
c[3] = (char) (b[i+2] & 0x3F);
|
850 |
|
|
} else {
|
851 |
|
|
c[3] = 64;
|
852 |
|
|
}
|
853 |
|
|
} else {
|
854 |
|
|
c[2] = 64;
|
855 |
|
|
c[3] = 64;
|
856 |
|
|
}
|
857 |
|
|
|
858 |
|
|
// Convert to base64 chars
|
859 |
|
|
for(int j = 0; j < 4; j++) {
|
860 |
|
|
if (c[j] < 26) {
|
861 |
|
|
c[j] += 'A';
|
862 |
|
|
} else if (c[j] < 52) {
|
863 |
|
|
c[j] = (char) (c[j] - 26 + 'a');
|
864 |
|
|
} else if (c[j] < 62) {
|
865 |
|
|
c[j] = (char) (c[j] - 52 + '0');
|
866 |
|
|
} else if (c[j] == 62) {
|
867 |
|
|
c[j] = '+';
|
868 |
|
|
} else if (c[j] == 63) {
|
869 |
|
|
c[j] = '/';
|
870 |
|
|
} else {
|
871 |
|
|
c[j] = '=';
|
872 |
|
|
}
|
873 |
|
|
}
|
874 |
|
|
|
875 |
|
|
sb.append(c);
|
876 |
|
|
i += 3;
|
877 |
|
|
remaining -= 3;
|
878 |
|
|
}
|
879 |
|
|
|
880 |
|
|
return sb.toString();
|
881 |
|
|
}
|
882 |
|
|
|
883 |
|
|
/**
|
884 |
|
|
* Convenience method for setting the given entry as a double.
|
885 |
|
|
* The double is converted with <code>Double.toString(double)</code>
|
886 |
|
|
* and then stored in the preference entry as that string.
|
887 |
|
|
*
|
888 |
|
|
* @exception NullPointerException if the key is null
|
889 |
|
|
* @exception IllegalArgumentException if the key length is to large
|
890 |
|
|
* @exception IllegalStateException when this node has been removed
|
891 |
|
|
*/
|
892 |
|
|
public void putDouble(String key, double value) {
|
893 |
|
|
put(key, Double.toString(value));
|
894 |
|
|
}
|
895 |
|
|
|
896 |
|
|
/**
|
897 |
|
|
* Convenience method for setting the given entry as a float.
|
898 |
|
|
* The float is converted with <code>Float.toString(float)</code>
|
899 |
|
|
* and then stored in the preference entry as that string.
|
900 |
|
|
*
|
901 |
|
|
* @exception NullPointerException if the key is null
|
902 |
|
|
* @exception IllegalArgumentException if the key length is to large
|
903 |
|
|
* @exception IllegalStateException when this node has been removed
|
904 |
|
|
*/
|
905 |
|
|
public void putFloat(String key, float value) {
|
906 |
|
|
put(key, Float.toString(value));
|
907 |
|
|
}
|
908 |
|
|
|
909 |
|
|
/**
|
910 |
|
|
* Convenience method for setting the given entry as an integer.
|
911 |
|
|
* The integer is converted with <code>Integer.toString(int)</code>
|
912 |
|
|
* and then stored in the preference entry as that string.
|
913 |
|
|
*
|
914 |
|
|
* @exception NullPointerException if the key is null
|
915 |
|
|
* @exception IllegalArgumentException if the key length is to large
|
916 |
|
|
* @exception IllegalStateException when this node has been removed
|
917 |
|
|
*/
|
918 |
|
|
public void putInt(String key, int value) {
|
919 |
|
|
put(key, Integer.toString(value));
|
920 |
|
|
}
|
921 |
|
|
|
922 |
|
|
/**
|
923 |
|
|
* Convenience method for setting the given entry as a long.
|
924 |
|
|
* The long is converted with <code>Long.toString(long)</code>
|
925 |
|
|
* and then stored in the preference entry as that string.
|
926 |
|
|
*
|
927 |
|
|
* @exception NullPointerException if the key is null
|
928 |
|
|
* @exception IllegalArgumentException if the key length is to large
|
929 |
|
|
* @exception IllegalStateException when this node has been removed
|
930 |
|
|
*/
|
931 |
|
|
public void putLong(String key, long value) {
|
932 |
|
|
put(key, Long.toString(value));
|
933 |
|
|
}
|
934 |
|
|
|
935 |
|
|
/**
|
936 |
|
|
* Removes the preferences entry from this preferences node.
|
937 |
|
|
* <p>
|
938 |
|
|
* The result will be immediatly visible in this VM, but may not be
|
939 |
|
|
* immediatly written to the backing store.
|
940 |
|
|
* <p>
|
941 |
|
|
* This implementation checks that the key is not larger then 80
|
942 |
|
|
* characters, gets the lock of this node, checks that the node has
|
943 |
|
|
* not been removed and calls <code>removeSpi</code> with the given key.
|
944 |
|
|
*
|
945 |
|
|
* @exception NullPointerException if the key is null
|
946 |
|
|
* @exception IllegalArgumentException if the key length is to large
|
947 |
|
|
* @exception IllegalStateException when this node has been removed
|
948 |
|
|
*/
|
949 |
|
|
public void remove(String key) {
|
950 |
|
|
if (key.length() > MAX_KEY_LENGTH)
|
951 |
|
|
throw new IllegalArgumentException(key);
|
952 |
|
|
|
953 |
|
|
synchronized(lock) {
|
954 |
|
|
if (isRemoved())
|
955 |
|
|
throw new IllegalStateException("Node removed");
|
956 |
|
|
|
957 |
|
|
removeSpi(key);
|
958 |
|
|
}
|
959 |
|
|
}
|
960 |
|
|
|
961 |
|
|
/**
|
962 |
|
|
* Removes all entries from this preferences node. May need access to the
|
963 |
|
|
* backing store to get and clear all entries.
|
964 |
|
|
* <p>
|
965 |
|
|
* The result will be immediatly visible in this VM, but may not be
|
966 |
|
|
* immediatly written to the backing store.
|
967 |
|
|
* <p>
|
968 |
|
|
* This implementation locks this node, checks that the node has not been
|
969 |
|
|
* removed and calls <code>keys()</code> to get a complete array of keys
|
970 |
|
|
* for this node. For every key found <code>removeSpi()</code> is called.
|
971 |
|
|
*
|
972 |
|
|
* @exception BackingStoreException when the backing store cannot be
|
973 |
|
|
* reached
|
974 |
|
|
* @exception IllegalStateException if this node has been removed
|
975 |
|
|
*/
|
976 |
|
|
public void clear() throws BackingStoreException {
|
977 |
|
|
synchronized(lock) {
|
978 |
|
|
if (isRemoved())
|
979 |
|
|
throw new IllegalStateException("Node Removed");
|
980 |
|
|
|
981 |
|
|
String[] keys = keys();
|
982 |
|
|
for (int i = 0; i < keys.length; i++) {
|
983 |
|
|
removeSpi(keys[i]);
|
984 |
|
|
}
|
985 |
|
|
}
|
986 |
|
|
}
|
987 |
|
|
|
988 |
|
|
/**
|
989 |
|
|
* Writes all preference changes on this and any subnode that have not
|
990 |
|
|
* yet been written to the backing store. This has no effect on the
|
991 |
|
|
* preference entries in this VM, but it makes sure that all changes
|
992 |
|
|
* are visible to other programs (other VMs might need to call the
|
993 |
|
|
* <code>sync()</code> method to actually see the changes to the backing
|
994 |
|
|
* store.
|
995 |
|
|
* <p>
|
996 |
|
|
* Locks this node, calls the <code>flushSpi()</code> method, gets all
|
997 |
|
|
* the (cached - already existing in this VM) subnodes and then calls
|
998 |
|
|
* <code>flushSpi()</code> on every subnode with this node unlocked and
|
999 |
|
|
* only that particular subnode locked.
|
1000 |
|
|
*
|
1001 |
|
|
* @exception BackingStoreException when the backing store cannot be
|
1002 |
|
|
* reached
|
1003 |
|
|
*/
|
1004 |
|
|
public void flush() throws BackingStoreException {
|
1005 |
|
|
flushNode(false);
|
1006 |
|
|
}
|
1007 |
|
|
|
1008 |
|
|
/**
|
1009 |
|
|
* Writes and reads all preference changes to and from this and any
|
1010 |
|
|
* subnodes. This makes sure that all local changes are written to the
|
1011 |
|
|
* backing store and that all changes to the backing store are visible
|
1012 |
|
|
* in this preference node (and all subnodes).
|
1013 |
|
|
* <p>
|
1014 |
|
|
* Checks that this node is not removed, locks this node, calls the
|
1015 |
|
|
* <code>syncSpi()</code> method, gets all the subnodes and then calls
|
1016 |
|
|
* <code>syncSpi()</code> on every subnode with this node unlocked and
|
1017 |
|
|
* only that particular subnode locked.
|
1018 |
|
|
*
|
1019 |
|
|
* @exception BackingStoreException when the backing store cannot be
|
1020 |
|
|
* reached
|
1021 |
|
|
* @exception IllegalStateException if this node has been removed
|
1022 |
|
|
*/
|
1023 |
|
|
public void sync() throws BackingStoreException {
|
1024 |
|
|
flushNode(true);
|
1025 |
|
|
}
|
1026 |
|
|
|
1027 |
|
|
|
1028 |
|
|
/**
|
1029 |
|
|
* Private helper method that locks this node and calls either
|
1030 |
|
|
* <code>flushSpi()</code> if <code>sync</code> is false, or
|
1031 |
|
|
* <code>flushSpi()</code> if <code>sync</code> is true. Then it gets all
|
1032 |
|
|
* the currently cached subnodes. For every subnode it calls this method
|
1033 |
|
|
* recursively with this node no longer locked.
|
1034 |
|
|
* <p>
|
1035 |
|
|
* Called by either <code>flush()</code> or <code>sync()</code>
|
1036 |
|
|
*/
|
1037 |
|
|
private void flushNode(boolean sync) throws BackingStoreException {
|
1038 |
|
|
String[] keys = null;
|
1039 |
|
|
synchronized(lock) {
|
1040 |
|
|
if (sync) {
|
1041 |
|
|
syncSpi();
|
1042 |
|
|
} else {
|
1043 |
|
|
flushSpi();
|
1044 |
|
|
}
|
1045 |
|
|
keys = (String[]) childCache.keySet().toArray(new String[]{});
|
1046 |
|
|
}
|
1047 |
|
|
|
1048 |
|
|
if (keys != null) {
|
1049 |
|
|
for (int i = 0; i < keys.length; i++) {
|
1050 |
|
|
// Have to lock this node again to access the childCache
|
1051 |
|
|
AbstractPreferences subNode;
|
1052 |
|
|
synchronized(this) {
|
1053 |
|
|
subNode = (AbstractPreferences) childCache.get(keys[i]);
|
1054 |
|
|
}
|
1055 |
|
|
|
1056 |
|
|
// The child could already have been removed from the cache
|
1057 |
|
|
if (subNode != null) {
|
1058 |
|
|
subNode.flushNode(sync);
|
1059 |
|
|
}
|
1060 |
|
|
}
|
1061 |
|
|
}
|
1062 |
|
|
}
|
1063 |
|
|
|
1064 |
|
|
/**
|
1065 |
|
|
* Removes this and all subnodes from the backing store and clears all
|
1066 |
|
|
* entries. After removal this instance will not be useable (except for
|
1067 |
|
|
* a few methods that don't throw a <code>InvalidStateException</code>),
|
1068 |
|
|
* even when a new node with the same path name is created this instance
|
1069 |
|
|
* will not be usable again.
|
1070 |
|
|
* <p>
|
1071 |
|
|
* Checks that this is not a root node. If not it locks the parent node,
|
1072 |
|
|
* then locks this node and checks that the node has not yet been removed.
|
1073 |
|
|
* Then it makes sure that all subnodes of this node are in the child cache,
|
1074 |
|
|
* by calling <code>childSpi()</code> on any children not yet in the cache.
|
1075 |
|
|
* Then for all children it locks the subnode and removes it. After all
|
1076 |
|
|
* subnodes have been purged the child cache is cleared, this nodes removed
|
1077 |
|
|
* flag is set and any listeners are called. Finally this node is removed
|
1078 |
|
|
* from the child cache of the parent node.
|
1079 |
|
|
*
|
1080 |
|
|
* @exception BackingStoreException when the backing store cannot be
|
1081 |
|
|
* reached
|
1082 |
|
|
* @exception IllegalStateException if this node has already been removed
|
1083 |
|
|
* @exception UnsupportedOperationException if this is a root node
|
1084 |
|
|
*/
|
1085 |
|
|
public void removeNode() throws BackingStoreException {
|
1086 |
|
|
// Check if it is a root node
|
1087 |
|
|
if (parent == null)
|
1088 |
|
|
throw new UnsupportedOperationException("Cannot remove root node");
|
1089 |
|
|
|
1090 |
|
|
synchronized(parent) {
|
1091 |
|
|
synchronized(this) {
|
1092 |
|
|
if (isRemoved())
|
1093 |
|
|
throw new IllegalStateException("Node Removed");
|
1094 |
|
|
|
1095 |
|
|
purge();
|
1096 |
|
|
}
|
1097 |
|
|
parent.childCache.remove(name);
|
1098 |
|
|
}
|
1099 |
|
|
}
|
1100 |
|
|
|
1101 |
|
|
/**
|
1102 |
|
|
* Private helper method used to completely remove this node.
|
1103 |
|
|
* Called by <code>removeNode</code> with the parent node and this node
|
1104 |
|
|
* locked.
|
1105 |
|
|
* <p>
|
1106 |
|
|
* Makes sure that all subnodes of this node are in the child cache,
|
1107 |
|
|
* by calling <code>childSpi()</code> on any children not yet in the
|
1108 |
|
|
* cache. Then for all children it locks the subnode and calls this method
|
1109 |
|
|
* on that node. After all subnodes have been purged the child cache is
|
1110 |
|
|
* cleared, this nodes removed flag is set and any listeners are called.
|
1111 |
|
|
*/
|
1112 |
|
|
private void purge() throws BackingStoreException
|
1113 |
|
|
{
|
1114 |
|
|
// Make sure all children have an AbstractPreferences node in cache
|
1115 |
|
|
String children[] = childrenNamesSpi();
|
1116 |
|
|
for (int i = 0; i < children.length; i++) {
|
1117 |
|
|
if (childCache.get(children[i]) == null)
|
1118 |
|
|
childCache.put(children[i], childSpi(children[i]));
|
1119 |
|
|
}
|
1120 |
|
|
|
1121 |
|
|
// purge all children
|
1122 |
|
|
Iterator i = childCache.values().iterator();
|
1123 |
|
|
while (i.hasNext()) {
|
1124 |
|
|
AbstractPreferences node = (AbstractPreferences) i.next();
|
1125 |
|
|
synchronized(node) {
|
1126 |
|
|
node.purge();
|
1127 |
|
|
}
|
1128 |
|
|
}
|
1129 |
|
|
|
1130 |
|
|
// Cache is empty now
|
1131 |
|
|
childCache.clear();
|
1132 |
|
|
|
1133 |
|
|
// remove this node
|
1134 |
|
|
removeNodeSpi();
|
1135 |
|
|
removed = true;
|
1136 |
|
|
|
1137 |
|
|
// XXX - check for listeners
|
1138 |
|
|
}
|
1139 |
|
|
|
1140 |
|
|
// listener methods
|
1141 |
|
|
|
1142 |
|
|
/**
|
1143 |
|
|
* XXX
|
1144 |
|
|
*/
|
1145 |
|
|
public void addNodeChangeListener(NodeChangeListener listener) {
|
1146 |
|
|
// XXX
|
1147 |
|
|
}
|
1148 |
|
|
|
1149 |
|
|
public void addPreferenceChangeListener(PreferenceChangeListener listener) {
|
1150 |
|
|
// XXX
|
1151 |
|
|
}
|
1152 |
|
|
|
1153 |
|
|
public void removeNodeChangeListener(NodeChangeListener listener) {
|
1154 |
|
|
// XXX
|
1155 |
|
|
}
|
1156 |
|
|
|
1157 |
|
|
public void removePreferenceChangeListener
|
1158 |
|
|
(PreferenceChangeListener listener)
|
1159 |
|
|
{
|
1160 |
|
|
// XXX
|
1161 |
|
|
}
|
1162 |
|
|
|
1163 |
|
|
// abstract spi methods
|
1164 |
|
|
|
1165 |
|
|
/**
|
1166 |
|
|
* Returns the names of the sub nodes of this preference node.
|
1167 |
|
|
* This method only has to return any not yet cached child names,
|
1168 |
|
|
* but may return all names if that is easier. It must not return
|
1169 |
|
|
* null when there are no children, it has to return an empty array
|
1170 |
|
|
* in that case. Since this method must consult the backing store to
|
1171 |
|
|
* get all the sub node names it may throw a BackingStoreException.
|
1172 |
|
|
* <p>
|
1173 |
|
|
* Called by <code>childrenNames()</code> with this node locked.
|
1174 |
|
|
*/
|
1175 |
|
|
protected abstract String[] childrenNamesSpi() throws BackingStoreException;
|
1176 |
|
|
|
1177 |
|
|
/**
|
1178 |
|
|
* Returns a child note with the given name.
|
1179 |
|
|
* This method is called by the <code>node()</code> method (indirectly
|
1180 |
|
|
* through the <code>getNode()</code> helper method) with this node locked
|
1181 |
|
|
* if a sub node with this name does not already exist in the child cache.
|
1182 |
|
|
* If the child node did not aleady exist in the backing store the boolean
|
1183 |
|
|
* field <code>newNode</code> of the returned node should be set.
|
1184 |
|
|
* <p>
|
1185 |
|
|
* Note that this method should even return a non-null child node if the
|
1186 |
|
|
* backing store is not available since it may not throw a
|
1187 |
|
|
* <code>BackingStoreException</code>.
|
1188 |
|
|
*/
|
1189 |
|
|
protected abstract AbstractPreferences childSpi(String name);
|
1190 |
|
|
|
1191 |
|
|
/**
|
1192 |
|
|
* Returns an (possibly empty) array with all the keys of the preference
|
1193 |
|
|
* entries of this node.
|
1194 |
|
|
* <p>
|
1195 |
|
|
* Called by <code>keys()</code> with this node locked if this node has
|
1196 |
|
|
* not been removed. May throw an exception when the backing store cannot
|
1197 |
|
|
* be accessed.
|
1198 |
|
|
*
|
1199 |
|
|
* @exception BackingStoreException when the backing store cannot be
|
1200 |
|
|
* reached
|
1201 |
|
|
*/
|
1202 |
|
|
protected abstract String[] keysSpi() throws BackingStoreException;
|
1203 |
|
|
|
1204 |
|
|
/**
|
1205 |
|
|
* Returns the value associated with the key in this preferences node or
|
1206 |
|
|
* null when the key does not exist in this preferences node.
|
1207 |
|
|
* <p>
|
1208 |
|
|
* Called by <code>key()</code> with this node locked after checking that
|
1209 |
|
|
* key is valid, not null and that the node has not been removed.
|
1210 |
|
|
* <code>key()</code> will catch any exceptions that this method throws.
|
1211 |
|
|
*/
|
1212 |
|
|
protected abstract String getSpi(String key);
|
1213 |
|
|
|
1214 |
|
|
/**
|
1215 |
|
|
* Sets the value of the given preferences entry for this node.
|
1216 |
|
|
* The implementation is not required to propagate the change to the
|
1217 |
|
|
* backing store immediatly. It may not throw an exception when it tries
|
1218 |
|
|
* to write to the backing store and that operation fails, the failure
|
1219 |
|
|
* should be registered so a later invocation of <code>flush()</code>
|
1220 |
|
|
* or <code>sync()</code> can signal the failure.
|
1221 |
|
|
* <p>
|
1222 |
|
|
* Called by <code>put()</code> with this node locked after checking that
|
1223 |
|
|
* key and value are valid and non-null.
|
1224 |
|
|
*/
|
1225 |
|
|
protected abstract void putSpi(String key, String value);
|
1226 |
|
|
|
1227 |
|
|
/**
|
1228 |
|
|
* Removes the given key entry from this preferences node.
|
1229 |
|
|
* The implementation is not required to propagate the change to the
|
1230 |
|
|
* backing store immediatly. It may not throw an exception when it tries
|
1231 |
|
|
* to write to the backing store and that operation fails, the failure
|
1232 |
|
|
* should be registered so a later invocation of <code>flush()</code>
|
1233 |
|
|
* or <code>sync()</code> can signal the failure.
|
1234 |
|
|
* <p>
|
1235 |
|
|
* Called by <code>remove()</code> with this node locked after checking
|
1236 |
|
|
* that the key is valid and non-null.
|
1237 |
|
|
*/
|
1238 |
|
|
protected abstract void removeSpi(String key);
|
1239 |
|
|
|
1240 |
|
|
/**
|
1241 |
|
|
* Writes all entries of this preferences node that have not yet been
|
1242 |
|
|
* written to the backing store and possibly creates this node in the
|
1243 |
|
|
* backing store, if it does not yet exist. Should only write changes to
|
1244 |
|
|
* this node and not write changes to any subnodes.
|
1245 |
|
|
* Note that the node can be already removed in this VM. To check if
|
1246 |
|
|
* that is the case the implementation can call <code>isRemoved()</code>.
|
1247 |
|
|
* <p>
|
1248 |
|
|
* Called (indirectly) by <code>flush()</code> with this node locked.
|
1249 |
|
|
*/
|
1250 |
|
|
protected abstract void flushSpi() throws BackingStoreException;
|
1251 |
|
|
|
1252 |
|
|
/**
|
1253 |
|
|
* Writes all entries of this preferences node that have not yet been
|
1254 |
|
|
* written to the backing store and reads any entries that have changed
|
1255 |
|
|
* in the backing store but that are not yet visible in this VM.
|
1256 |
|
|
* Should only sync this node and not change any of the subnodes.
|
1257 |
|
|
* Note that the node can be already removed in this VM. To check if
|
1258 |
|
|
* that is the case the implementation can call <code>isRemoved()</code>.
|
1259 |
|
|
* <p>
|
1260 |
|
|
* Called (indirectly) by <code>sync()</code> with this node locked.
|
1261 |
|
|
*/
|
1262 |
|
|
protected abstract void syncSpi() throws BackingStoreException;
|
1263 |
|
|
|
1264 |
|
|
/**
|
1265 |
|
|
* Clears this node from this VM and removes it from the backing store.
|
1266 |
|
|
* After this method has been called the node is marked as removed.
|
1267 |
|
|
* <p>
|
1268 |
|
|
* Called (indirectly) by <code>removeNode()</code> with this node locked
|
1269 |
|
|
* after all the sub nodes of this node have already been removed.
|
1270 |
|
|
*/
|
1271 |
|
|
protected abstract void removeNodeSpi() throws BackingStoreException;
|
1272 |
|
|
}
|