/*
* Copyright (c) 2005, 2007, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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/*
* (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
* (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved
*
* The original version of this source code and documentation
* is copyrighted and owned by Taligent, Inc., a wholly-owned
* subsidiary of IBM. These materials are provided under terms
* of a License Agreement between Taligent and Sun. This technology
* is protected by multiple US and International patents.
*
* This notice and attribution to Taligent may not be removed.
* Taligent is a registered trademark of Taligent, Inc.
*
*/
package sun.util.resources;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.ResourceBundle;
import java.util.Set;
import sun.util.ResourceBundleEnumeration;
/**
* Subclass of <code>ResourceBundle</code> which mimics
* <code>ListResourceBundle</code>, but provides more hooks
* for specialized subclass behavior. For general description,
* see {@link java.util.ListResourceBundle}.
* <p>
* This class leaves handleGetObject non-final, and
* adds a method createMap which allows subclasses to
* use specialized Map implementations.
*/
public abstract class OpenListResourceBundle extends ResourceBundle {
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
protected OpenListResourceBundle() {
}
// Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.
public Object handleGetObject(String key) {
if (key == null) {
throw new NullPointerException();
}
loadLookupTablesIfNecessary();
return lookup.get(key); // this class ignores locales
}
/**
* Implementation of ResourceBundle.getKeys.
*/
public Enumeration<String> getKeys() {
ResourceBundle parent = this.parent;
return new ResourceBundleEnumeration(handleGetKeys(),
(parent != null) ? parent.getKeys() : null);
}
/**
* Returns a set of keys provided in this resource bundle
*/
public Set<String> handleGetKeys() {
loadLookupTablesIfNecessary();
return lookup.keySet();
}
/**
* Returns the parent bundle
*/
public OpenListResourceBundle getParent() {
return (OpenListResourceBundle)parent;
}
/**
* See ListResourceBundle class description.
*/
abstract protected Object[][] getContents();
/**
* Load lookup tables if they haven't been loaded already.
*/
void loadLookupTablesIfNecessary() {
if (lookup == null) {
loadLookup();
}
}
/**
* We lazily load the lookup hashtable. This function does the
* loading.
*/
private synchronized void loadLookup() {
if (lookup != null)
return;
Object[][] contents = getContents();
Map temp = createMap(contents.length);
for (int i = 0; i < contents.length; ++i) {
// key must be non-null String, value must be non-null
String key = (String) contents[i][0];
Object value = contents[i][1];
if (key == null || value == null) {
throw new NullPointerException();
}
temp.put(key, value);
}
lookup = temp;
}
/**
* Lets subclasses provide specialized Map implementations.
* Default uses HashMap.
*/
protected Map createMap(int size) {
return new HashMap(size);
}
private Map lookup = null;
}