Config


1   /*
2    * Copyright 2001-2004 The Apache Software Foundation.
3    * 
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package org.apache.juddi.util;
17  
18  import java.net.MalformedURLException  ;
19  import java.net.URL  ;
20  import java.util.Enumeration  ;
21  import java.util.Iterator  ;
22  import java.util.Properties  ;
23  import java.util.SortedSet  ;
24  import java.util.TreeSet  ;
25  
26  import org.apache.commons.logging.Log;
27  import org.apache.commons.logging.LogFactory;
28  import org.apache.juddi.registry.RegistryEngine;
29  
30  /**
31   * This class provides read access to key/value pairs loaded
32   * from a properties file.
33   *
34   * @author Steve Viens (sviens@apache.org)
35   */
36  public class Config extends Properties  
37  {
38    // private reference to the log
39    private static Log log = LogFactory.getLog(Config.class);
40  
41    // shared instance
42    static Config config;
43  
44    /**
45     * shared Config constructor. Made private to 
46     * avoid creation of more than one Config.
47     */
48    private Config()
49    {
50      super();
51    }
52  
53    /**
54     * Returns a reference to the singleton Properties instance.
55     *
56     * @return Config A reference to the singleton Properties instance.
57     */
58    public static void addProperties(Properties   props)
59    {
60      if (config == null)
61        config = createConfig();
62      config.putAll(props);
63    }
64  
65    /**
66     * Returns a reference to the singleton Properties instance.
67     *
68     * @return Config A reference to the singleton Properties instance.
69     */
70    public static Properties   getProperties()
71    {
72      if (config == null)
73        config = createConfig();
74      return config;
75    }
76  
77    /**
78     *
79     */
80    public static String   getOperator()
81    {
82      return getStringProperty(RegistryEngine.PROPNAME_OPERATOR_NAME,
83                RegistryEngine.DEFAULT_OPERATOR_NAME);    
84    }
85  
86    /**
87     *
88     */
89    public static String   getDiscoveryURL()
90    {
91      return getStringProperty(RegistryEngine.PROPNAME_DISCOVERY_URL,
92                RegistryEngine.DEFAULT_DISCOVERY_URL);
93    }
94  
95    /**
96     *
97     */
98    public static int getMaxNameLengthAllowed()
99    {
100     return getIntProperty(RegistryEngine.PROPNAME_MAX_NAME_LENGTH,
101               RegistryEngine.DEFAULT_MAX_NAME_LENGTH);
102   }
103 
104   /**
105    *
106    */
107   public static int getMaxNameElementsAllowed()
108   {
109     return getIntProperty(RegistryEngine.PROPNAME_MAX_NAME_ELEMENTS,
110               RegistryEngine.DEFAULT_MAX_NAME_ELEMENTS);
111   }
112 
113   /**
114    * Retrieves a configuration property as a String object.
115    * Loads the juddi.properties file if not already initialized.
116    *
117    * @param key Name of the property to be returned.
118    * @return  Value of the property as a string or null if no property found.
119    */
120   public static String   getStringProperty(String   key, String   defaultValue)
121   {
122     String   stringVal = defaultValue;
123 
124     String   propValue = getStringProperty(key);
125     if (propValue != null)
126       stringVal = propValue;
127 
128     return stringVal;
129   }
130 
131   /**
132    * Get a configuration property as an int primitive.
133    *
134    * @param key Name of the numeric property to be returned.
135    * @return Value of the property as an Integer or null if no property found.
136    */
137   public static int getIntProperty(String   key, int defaultValue)
138   {
139     int intVal = defaultValue;
140 
141     String   propValue = getStringProperty(key);
142     if (propValue != null)
143       intVal = Integer.parseInt(propValue);
144 
145     return intVal;
146   }
147 
148   /**
149    * Get a configuration property as an long primitive.
150    *
151    * @param key Name of the numeric property to be returned.
152    * @return  Value of the property as an Long or null if no property found.
153    */
154   public static long getLongProperty(String   key, long defaultValue)
155   {
156     long longVal = defaultValue;
157 
158     String   propValue = getStringProperty(key);
159     if (propValue != null)
160       longVal = Long.parseLong(propValue);
161 
162     return longVal;
163   }
164 
165   /**
166    * Get a configuration property as a boolean primitive. Note
167    * that the value of the returned Boolean will be false if
168    * the property sought after exists but is not equal to
169    * "true" (ignoring case).
170    *
171    * @param key Name of the numeric property to be returned.
172    * @return Value of the property as an Boolean or null if no property found.
173    */
174   public static boolean getBooleanProperty(String   key, boolean defaultValue)
175   {
176     boolean boolVal = defaultValue;
177 
178     String   propValue = getStringProperty(key);
179     if ((propValue != null) && (propValue.equalsIgnoreCase("true")))
180       boolVal = true;
181 
182     return boolVal;
183   }
184 
185   /**
186    * Get a configuration property as a URL object.
187    *
188    * @param key Name of the url property to be returned.
189    * @return Value of the property as an URL or null if no property found.
190    */
191   public static URL   getURLProperty(String   key, URL   defaultValue)
192   {
193     URL   urlVal = defaultValue;
194 
195     String   propValue = getStringProperty(key);
196     if (propValue != null)
197     {
198       try
199       {
200         urlVal = new URL  (propValue);
201       }
202       catch (MalformedURLException   muex)
203       {
204         log.error(
205           "The " + key + " property value is invalid: " + propValue,muex);
206       }
207     }
208 
209     return urlVal;
210   }
211 
212   /**
213    * Retrieves a configuration property as a String object.
214    * Loads the juddi.properties file if not already initialized.
215    *
216    * @param key Name of the property to be returned.
217    * @return  Value of the property as a string or null if no property found.
218    */
219   public static String   getStringProperty(String   key)
220   {
221     if (config == null)
222       config = createConfig();
223 
224     // no properties to look into, return null
225     if (config == null)
226       return null;
227 
228     // no property name/key to lookup, return null
229     if (key == null)
230       return null;
231 
232     return config.getProperty(key);
233   }
234 
235   /**
236    * Sets a property value in jUDDI's property
237    * registry.  Loads the juddi.properties file if
238    * not already initialized.
239    *
240    * @param name Name of the property to be returned.
241    * @param value Property value as a string.
242    */
243   public static void setStringProperty(String   name, String   value)
244   {
245     if (config == null)
246       config = createConfig();
247 
248     // no properties to save to, just return
249     if (config == null)
250       return;
251 
252     // no property name/key, just return
253     if (name == null)
254       return;
255 
256     // no property value, attempt removal (otherwise save/replace)
257     if (value == null)
258       config.remove(name);
259     else
260       config.setProperty(name, value); // save or replace prop value
261   }
262 
263   /**
264    * Creates a single (singleton) instance of "org.util.Config"
265    *
266    * @return Config A reference to the singleton Config instance.
267    */
268   private static synchronized Config createConfig()
269   {
270     // If multiple threads are waiting to envoke
271     // this method only allow the first one to do so.
272 
273     if (config == null)
274       config = new Config();
275     return config;
276   }
277 
278   /**
279    * Returns a String containing a pipe-delimited ('|') list
280    * of name/value pairs.
281    * @return String pipe-delimited list of name/value pairs.
282    */
283   public String   toString()
284   {
285     // let's create a place to put the property information
286     StringBuffer   buff = new StringBuffer  (100);
287 
288     // gran an enumeration of the property names (or keys)
289     Enumeration   propKeys = keys();
290     while (propKeys.hasMoreElements())
291     {
292       // extract the Property Name (aka Key) and Value
293       String   propName = (String  ) propKeys.nextElement();
294       String   propValue = getProperty(propName);
295 
296       // append the name=value pair to the return buffer
297       buff.append(propName.trim());
298       buff.append("=");
299       buff.append(propValue.trim());
300       buff.append("\n");
301     }
302 
303     return buff.toString();
304   }
305 
306   /***************************************************************************/
307   /***************************** TEST DRIVER *********************************/
308   /***************************************************************************/
309 
310   public static void main(String  [] args)
311   {
312     Properties   sysProps = null;
313     SortedSet   sortedPropsSet = null;
314 
315     sysProps = Config.getProperties();
316     sortedPropsSet = new TreeSet  (sysProps.keySet());
317     for (Iterator   keys = sortedPropsSet.iterator(); keys.hasNext();)
318     {
319       String   key = (String  ) keys.next();
320       System.out.println(key + ": " + sysProps.getProperty(key));
321     }
322   }
323 }
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags