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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    * 
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   * 
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  
19  package org.apache.commons.modeler;
20  
21  
22  import java.io.Serializable;
23  import java.lang.reflect.Method;
24  
25  import javax.management.Descriptor;
26  import javax.management.modelmbean.ModelMBeanAttributeInfo;
27  
28  
29  /**
30   * <p>Internal configuration information for an <code>Attribute</code>
31   * descriptor.</p>
32   *
33   * @author Craig R. McClanahan
34   * @version $Revision: 480402 $ $Date: 2006-11-29 04:43:23 +0000 (Wed, 29 Nov 2006) $
35   */
36  
37  public class AttributeInfo extends FeatureInfo implements Serializable {
38      static final long serialVersionUID = -2511626862303972143L;
39  
40      // ----------------------------------------------------- Instance Variables
41  
42  
43      /**
44       * The <code>ModelMBeanAttributeInfo</code> object that corresponds
45       * to this <code>AttributeInfo</code> instance.
46       */
47      protected transient ModelMBeanAttributeInfo info = null;
48      protected String displayName = null;
49      protected String getMethod = null;
50      protected String setMethod = null;
51  
52      protected transient Method getMethodObj = null;
53      protected transient Method setMethodObj = null;
54  
55      protected boolean readable = true;
56      protected boolean writeable = true;
57  
58      protected boolean is = false;
59      protected String type = null;
60  
61      protected String persist;
62      protected String defaultStringValue;
63      // ------------------------------------------------------------- Properties
64  
65  
66      /**
67       * Override the <code>description</code> property setter.
68       *
69       * @param description The new description
70       */
71      public void setDescription(String description) {
72          super.setDescription(description);
73          this.info = null;
74      }
75  
76      /**
77       * Override the <code>name</code> property setter.
78       *
79       * @param name The new name
80       */
81      public void setName(String name) {
82          super.setName(name);
83          this.info = null;
84      }
85  
86      /**
87       * The display name of this attribute.
88       */
89      public String getDisplayName() {
90          return (this.displayName);
91      }
92  
93      public void setDisplayName(String displayName) {
94          this.displayName = displayName;
95      }
96  
97      /**
98       * The name of the property getter method, if non-standard.
99       */
100     public String getGetMethod() {
101         return (this.getMethod);
102     }
103 
104     public void setGetMethod(String getMethod) {
105         this.getMethod = getMethod;
106         this.info = null;
107     }
108 
109     public Method getGetMethodObj() {
110         return getMethodObj;
111     }
112 
113     public void setGetMethodObj(Method getMethodObj) {
114         this.getMethodObj = getMethodObj;
115     }
116 
117     public Method getSetMethodObj() {
118         return setMethodObj;
119     }
120 
121     public void setSetMethodObj(Method setMethodObj) {
122         this.setMethodObj = setMethodObj;
123     }
124 
125     /**
126      * Is this a boolean attribute with an "is" getter?
127      */
128     public boolean isIs() {
129         return (this.is);
130     }
131 
132     public void setIs(boolean is) {
133         this.is = is;
134         this.info = null;
135     }
136 
137 
138     /**
139      * Is this attribute readable by management applications?
140      */
141     public boolean isReadable() {
142         return (this.readable);
143     }
144 
145     public void setReadable(boolean readable) {
146         this.readable = readable;
147         this.info = null;
148     }
149 
150 
151     /**
152      * The name of the property setter method, if non-standard.
153      */
154     public String getSetMethod() {
155         return (this.setMethod);
156     }
157 
158     public void setSetMethod(String setMethod) {
159         this.setMethod = setMethod;
160         this.info = null;
161     }
162 
163 
164     /**
165      * The fully qualified Java class name of this attribute.
166      */
167     public String getType() {
168         return (this.type);
169     }
170 
171     public void setType(String type) {
172         this.type = type;
173         this.info = null;
174     }
175 
176 
177     /**
178      * Is this attribute writeable by management applications?
179      */
180     public boolean isWriteable() {
181         return (this.writeable);
182     }
183 
184     public void setWriteable(boolean writeable) {
185         this.writeable = writeable;
186         this.info = null;
187     }
188 
189     /** Persistence policy.
190      * All persistent attributes should have this attribute set.
191      * Valid values:
192      *   ???
193      */
194     public String getPersist() {
195         return persist;
196     }
197 
198     public void setPersist(String persist) {
199         this.persist = persist;
200     }
201 
202     /** Default value. If set, it can provide info to the user and
203      * it can be used by persistence mechanism to generate a more compact
204      * representation ( a value may not be saved if it's default )
205      */
206     public String getDefault() {
207         return defaultStringValue;
208     }
209 
210     public void setDefault(String defaultStringValue) {
211         this.defaultStringValue = defaultStringValue;
212     }
213 
214 
215     // --------------------------------------------------------- Public Methods
216 
217 
218     /**
219      * Create and return a <code>ModelMBeanAttributeInfo</code> object that
220      * corresponds to the attribute described by this instance.
221      */
222     public ModelMBeanAttributeInfo createAttributeInfo() {
223         // Return our cached information (if any)
224         if (info != null)
225             return (info);
226         if((getMethodObj != null) || (setMethodObj != null) ) {
227             try {
228                 info=new ModelMBeanAttributeInfo(getName(), getDescription(),
229                                         getMethodObj,  setMethodObj);
230                 return info;
231             } catch( Exception ex) {
232                 ex.printStackTrace();
233             }
234         }
235 
236         // Create and return a new information object
237         info = new ModelMBeanAttributeInfo
238             (getName(), getType(), getDescription(),
239              isReadable(), isWriteable(), false);
240         Descriptor descriptor = info.getDescriptor();
241         if (getDisplayName() != null)
242             descriptor.setField("displayName", getDisplayName());
243         if (isReadable()) {
244             if (getGetMethod() != null)
245                 descriptor.setField("getMethod", getGetMethod());
246             else
247                 descriptor.setField("getMethod",
248                                     getMethodName(getName(), true, isIs()));
249         }
250         if (isWriteable()) {
251             if (getSetMethod() != null)
252                 descriptor.setField("setMethod", getSetMethod());
253             else
254                 descriptor.setField("setMethod",
255                                     getMethodName(getName(), false, false));
256         }
257         addFields(descriptor);
258         info.setDescriptor(descriptor);
259         return (info);
260 
261     }
262 
263 
264     /**
265      * Return a string representation of this attribute descriptor.
266      */
267     public String toString() {
268 
269         StringBuffer sb = new StringBuffer("AttributeInfo[");
270         sb.append("name=");
271         sb.append(name);
272         sb.append(", description=");
273         sb.append(description);
274         if (!readable) {
275             sb.append(", readable=");
276             sb.append(readable);
277         }
278         sb.append(", type=");
279         sb.append(type);
280         if (!writeable) {
281             sb.append(", writeable=");
282             sb.append(writeable);
283         }
284         sb.append("]");
285         return (sb.toString());
286 
287     }
288 
289 
290     // -------------------------------------------------------- Private Methods
291 
292 
293     /**
294      * Create and return the name of a default property getter or setter
295      * method, according to the specified values.
296      *
297      * @param name Name of the property itself
298      * @param getter Do we want a get method (versus a set method)?
299      * @param is If returning a getter, do we want the "is" form?
300      */
301     private String getMethodName(String name, boolean getter, boolean is) {
302 
303         StringBuffer sb = new StringBuffer();
304         if (getter) {
305             if (is)
306                 sb.append("is");
307             else
308                 sb.append("get");
309         } else
310             sb.append("set");
311         sb.append(Character.toUpperCase(name.charAt(0)));
312         sb.append(name.substring(1));
313         return (sb.toString());
314 
315     }
316 
317 
318 }