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 * DefaultConfiguration.java 029 * ------------------------- 030 * (C)opyright 2003, 2004, by Thomas Morgner and Contributors. 031 * 032 * Original Author: Thomas Morgner; 033 * Contributor(s): David Gilbert (for Object Refinery Limited); 034 * 035 * $Id: DefaultConfiguration.java,v 1.6 2008/09/10 09:21:30 mungady Exp $ 036 * 037 * Changes 038 * ------- 039 * 04.06.2003 : Initial version (TM); 040 * 041 */ 042 043 package org.jfree.util; 044 045 import java.util.Collections; 046 import java.util.Enumeration; 047 import java.util.Iterator; 048 import java.util.Properties; 049 import java.util.TreeSet; 050 051 import org.jfree.base.config.ModifiableConfiguration; 052 053 /** 054 * Default configuration. 055 * 056 * @author Thomas Morgner. 057 */ 058 public class DefaultConfiguration extends Properties 059 implements ModifiableConfiguration 060 { 061 062 /** 063 * Creates an empty property list with no default values. 064 */ 065 public DefaultConfiguration() 066 { 067 super(); 068 } 069 070 /** 071 * Returns the configuration property with the specified key. 072 * 073 * @param key the property key. 074 * @return the property value. 075 */ 076 public String getConfigProperty(final String key) 077 { 078 return getProperty(key); 079 } 080 081 /** 082 * Returns the configuration property with the specified key (or the 083 * specified default value if there is no such property). 084 * <p/> 085 * If the property is not defined in this configuration, the code will 086 * lookup the property in the parent configuration. 087 * 088 * @param key the property key. 089 * @param defaultValue the default value. 090 * @return the property value. 091 */ 092 public String getConfigProperty(final String key, final String defaultValue) 093 { 094 return getProperty(key, defaultValue); 095 } 096 097 /** 098 * Searches all property keys that start with a given prefix. 099 * 100 * @param prefix the prefix that all selected property keys should share 101 * @return the properties as iterator. 102 */ 103 public Iterator findPropertyKeys(final String prefix) 104 { 105 final TreeSet collector = new TreeSet(); 106 final Enumeration enum1 = keys(); 107 while (enum1.hasMoreElements()) 108 { 109 final String key = (String) enum1.nextElement(); 110 if (key.startsWith(prefix)) 111 { 112 if (collector.contains(key) == false) 113 { 114 collector.add(key); 115 } 116 } 117 } 118 return Collections.unmodifiableSet(collector).iterator(); 119 } 120 121 /** 122 * Returns an enumeration of the property keys. 123 * 124 * @return An enumeration of the property keys. 125 */ 126 public Enumeration getConfigProperties() 127 { 128 return keys(); 129 } 130 131 /** 132 * Sets the value of a configuration property. 133 * 134 * @param key the property key. 135 * @param value the property value. 136 */ 137 public void setConfigProperty(final String key, final String value) 138 { 139 if (value == null) 140 { 141 remove(key); 142 } 143 else 144 { 145 setProperty(key, value); 146 } 147 } 148 }