001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 * 019 */ 020package org.apache.directory.shared.util; 021 022 023import java.util.Dictionary; 024import java.util.Enumeration; 025import java.util.prefs.Preferences; 026import java.util.prefs.BackingStoreException; 027 028import org.apache.directory.shared.i18n.I18n; 029 030 031/** 032 * A wrapper around Preferences to access it as a Dictionary. 033 * 034 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 035 */ 036public class PreferencesDictionary extends Dictionary<String,String> 037{ 038 /** the underlying wrapped preferences object */ 039 private final Preferences prefs; 040 041 042 // ------------------------------------------------------------------------ 043 // C O N S T R U C T O R 044 // ------------------------------------------------------------------------ 045 046 public PreferencesDictionary( Preferences prefs ) 047 { 048 this.prefs = prefs; 049 } 050 051 052 // ------------------------------------------------------------------------ 053 // E X T R A M E T H O D S 054 // ------------------------------------------------------------------------ 055 056 /** 057 * Gets the Preferences used as the backing store for this Dictionary. 058 * 059 * @return the underlying Preferences object 060 */ 061 public Preferences getPreferences() 062 { 063 return prefs; 064 } 065 066 067 // ------------------------------------------------------------------------ 068 // D I C T I O N A R Y M E T H O D S 069 // ------------------------------------------------------------------------ 070 071 public int size() 072 { 073 try 074 { 075 return prefs.keys().length; 076 } 077 catch ( BackingStoreException e ) 078 { 079 throw new RuntimeException( I18n.err( I18n.ERR_04423 ), e ); 080 } 081 } 082 083 084 public boolean isEmpty() 085 { 086 try 087 { 088 return prefs.keys().length == 0; 089 } 090 catch ( BackingStoreException e ) 091 { 092 throw new RuntimeException( I18n.err( I18n.ERR_04423 ), e ); 093 } 094 } 095 096 097 @SuppressWarnings("unchecked") 098 public Enumeration<String> elements() 099 { 100 try 101 { 102 return new ArrayEnumeration( prefs.keys() ) 103 { 104 public String nextElement() 105 { 106 String key = ( String ) super.nextElement(); 107 108 return prefs.get( key, null ); 109 } 110 }; 111 } 112 catch ( BackingStoreException e ) 113 { 114 throw new RuntimeException( I18n.err( I18n.ERR_04423 ), e ); 115 } 116 } 117 118 119 @SuppressWarnings("unchecked") 120 public Enumeration<String> keys() 121 { 122 try 123 { 124 return new ArrayEnumeration( prefs.keys() ); 125 } 126 catch ( BackingStoreException e ) 127 { 128 throw new RuntimeException( I18n.err( I18n.ERR_04423 ), e ); 129 } 130 } 131 132 133 public String get( Object key ) 134 { 135 if ( key instanceof String ) 136 { 137 return prefs.get( ( String ) key, null ); 138 } 139 140 return prefs.get( key.toString(), null ); 141 } 142 143 144 public String remove( Object key ) 145 { 146 String retval = get( key ); 147 148 if ( key instanceof String ) 149 { 150 prefs.remove( ( String ) key ); 151 } 152 else 153 { 154 prefs.remove( key.toString() ); 155 } 156 157 return retval; 158 } 159 160 161 public String put( String key, String value ) 162 { 163 String retval = get( key ); 164 165 prefs.put( key, value ); 166 167 return retval; 168 } 169}