001 /* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jcommon/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * ---------------------------------
028 * ExtendedConfigurationWrapper.java
029 * ---------------------------------
030 * (C)opyright 2002-2005, by Thomas Morgner and Contributors.
031 *
032 * Original Author: Thomas Morgner;
033 * Contributor(s): David Gilbert (for Object Refinery Limited);
034 *
035 * $Id: ExtendedConfigurationWrapper.java,v 1.8 2008/09/10 09:22:04 mungady Exp $
036 *
037 * Changes
038 * -------
039 * 20-May-2005 : Initial version.
040 */
041
042 package org.jfree.util;
043
044 import java.util.Enumeration;
045 import java.util.Iterator;
046
047 /**
048 * A wrapper for the extended configuration interface around a plain configuration.
049 *
050 * @author Thomas Morgner
051 */
052 public class ExtendedConfigurationWrapper
053 implements ExtendedConfiguration
054 {
055 /** The base configuration. */
056 private Configuration parent;
057
058 /**
059 * Creates a wrapper around the given configuration.
060 *
061 * @param parent the wrapped up configuration.
062 * @throws NullPointerException if the parent is null.
063 */
064 public ExtendedConfigurationWrapper (final Configuration parent)
065 {
066 if (parent == null)
067 {
068 throw new NullPointerException("Parent given must not be null");
069 }
070 this.parent = parent;
071 }
072
073 /**
074 * Returns the boolean value of a given configuration property. The boolean value true
075 * is returned, if the contained string is equal to 'true'.
076 *
077 * @param name the name of the property
078 * @return the boolean value of the property.
079 */
080 public boolean getBoolProperty (final String name)
081 {
082 return getBoolProperty(name, false);
083 }
084
085 /**
086 * Returns the boolean value of a given configuration property. The boolean value true
087 * is returned, if the contained string is equal to 'true'. If the property is not set,
088 * the default value is returned.
089 *
090 * @param name the name of the property
091 * @param defaultValue the default value to be returned if the property is not set
092 * @return the boolean value of the property.
093 */
094 public boolean getBoolProperty (final String name,
095 final boolean defaultValue)
096 {
097 return "true".equals(this.parent.getConfigProperty(name, String.valueOf(defaultValue)));
098 }
099
100 /**
101 * Returns a given property as int value. Zero is returned if the
102 * property value is no number or the property is not set.
103 *
104 * @param name the name of the property
105 * @return the parsed number value or zero
106 */
107 public int getIntProperty (final String name)
108 {
109 return getIntProperty(name, 0);
110 }
111
112 /**
113 * Returns a given property as int value. The specified default value is returned if the
114 * property value is no number or the property is not set.
115 *
116 * @param name the name of the property
117 * @param defaultValue the value to be returned if the property is no integer value
118 * @return the parsed number value or the specified default value
119 */
120 public int getIntProperty (final String name,
121 final int defaultValue)
122 {
123 final String retval = this.parent.getConfigProperty(name);
124 if (retval == null)
125 {
126 return defaultValue;
127 }
128 try
129 {
130 return Integer.parseInt(retval);
131 }
132 catch (Exception e)
133 {
134 return defaultValue;
135 }
136 }
137
138 /**
139 * Checks, whether a given property is defined.
140 *
141 * @param name the name of the property
142 * @return true, if the property is defined, false otherwise.
143 */
144 public boolean isPropertySet (final String name)
145 {
146 return this.parent.getConfigProperty(name) != null;
147 }
148
149 /**
150 * Returns all keys with the given prefix.
151 *
152 * @param prefix the prefix
153 * @return the iterator containing all keys with that prefix
154 */
155 public Iterator findPropertyKeys (final String prefix)
156 {
157 return this.parent.findPropertyKeys(prefix);
158 }
159
160 /**
161 * Returns the configuration property with the specified key.
162 *
163 * @param key the property key.
164 * @return the property value.
165 */
166 public String getConfigProperty (final String key)
167 {
168 return this.parent.getConfigProperty(key);
169 }
170
171 /**
172 * Returns the configuration property with the specified key (or the specified default
173 * value if there is no such property).
174 * <p/>
175 * If the property is not defined in this configuration, the code will lookup the
176 * property in the parent configuration.
177 *
178 * @param key the property key.
179 * @param defaultValue the default value.
180 * @return the property value.
181 */
182 public String getConfigProperty (final String key, final String defaultValue)
183 {
184 return this.parent.getConfigProperty(key, defaultValue);
185 }
186
187 /**
188 * Returns an enumeration of the configuration properties.
189 *
190 * @return An enumeration.
191 */
192 public Enumeration getConfigProperties()
193 {
194 return this.parent.getConfigProperties();
195 }
196
197 /**
198 * Returns a clone of this instance.
199 *
200 * @return A clone.
201 *
202 * @throws CloneNotSupportedException if there is a problem cloning.
203 */
204 public Object clone () throws CloneNotSupportedException
205 {
206 ExtendedConfigurationWrapper wrapper = (ExtendedConfigurationWrapper) super.clone();
207 wrapper.parent = (Configuration) this.parent.clone();
208 return this.parent;
209 }
210 }