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1   /*
2    * $Id: DynaActionForm.java 471754 2006-11-06 14:55:09Z husted $
3    *
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *  http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  package org.apache.struts.action;
22  
23  import org.apache.commons.beanutils.ConversionException;
24  import org.apache.commons.beanutils.DynaBean;
25  import org.apache.commons.beanutils.DynaClass;
26  import org.apache.commons.beanutils.DynaProperty;
27  import org.apache.struts.config.FormBeanConfig;
28  import org.apache.struts.config.FormPropertyConfig;
29  
30  import javax.servlet.ServletRequest;
31  import javax.servlet.http.HttpServletRequest;
32  
33  import java.lang.reflect.Array;
34  
35  import java.util.HashMap;
36  import java.util.Iterator;
37  import java.util.List;
38  import java.util.Map;
39  import java.util.StringTokenizer;
40  
41  /**
42   * <p>Specialized subclass of <code>ActionForm</code> that allows the creation
43   * of form beans with dynamic sets of properties, without requiring the
44   * developer to create a Java class for each type of form bean.</p>
45   *
46   * <p><strong>USAGE NOTE</strong> - Since Struts 1.1, the <code>reset</code>
47   * method no longer initializes property values to those specified in
48   * <code>&lt;form-property&gt;</code> elements in the Struts module
49   * configuration file.  If you wish to utilize that behavior, the simplest
50   * solution is to subclass <code>DynaActionForm</code> and call the
51   * <code>initialize</code> method inside it.</p>
52   *
53   * @version $Rev: 471754 $ $Date: 2005-11-12 11:52:08 -0500 (Sat, 12 Nov 2005)
54   *          $
55   * @since Struts 1.1
56   */
57  public class DynaActionForm extends ActionForm implements DynaBean {
58      // ----------------------------------------------------- Instance Variables
59  
60      /**
61       * <p>The <code>DynaActionFormClass</code> with which we are associated.
62       * </p>
63       */
64      protected DynaActionFormClass dynaClass = null;
65  
66      /**
67       * <p>The set of property values for this <code>DynaActionForm</code>,
68       * keyed by property name.</p>
69       */
70      protected HashMap dynaValues = new HashMap();
71  
72      // ----------------------------------------------------- ActionForm Methods
73  
74      /**
75       * <p>Initialize all bean properties to their initial values, as specified
76       * in the {@link FormPropertyConfig} elements associated with the
77       * definition of this <code>DynaActionForm</code>.</p>
78       *
79       * @param mapping The mapping used to select this instance
80       */
81      public void initialize(ActionMapping mapping) {
82          String name = mapping.getName();
83  
84          if (name == null) {
85              return;
86          }
87  
88          FormBeanConfig config =
89              mapping.getModuleConfig().findFormBeanConfig(name);
90  
91          if (config == null) {
92              return;
93          }
94  
95          initialize(config);
96      }
97  
98      /**
99       * <p>Initialize the specified form bean.</p>
100      *
101      * @param config The configuration for the form bean to initialize.
102      */
103     public void initialize(FormBeanConfig config) {
104         FormPropertyConfig[] props = config.findFormPropertyConfigs();
105 
106         for (int i = 0; i < props.length; i++) {
107             set(props[i].getName(), props[i].initial());
108         }
109     }
110 
111     // :FIXME: Is there any point in retaining these reset methods
112     // since they now simply replicate the superclass behavior?
113 
114     /**
115      * <p>Reset bean properties to their default state, as needed. This method
116      * is called before the properties are repopulated by the controller.</p>
117      *
118      * <p>The default implementation attempts to forward to the HTTP version
119      * of this method.</p>
120      *
121      * @param mapping The mapping used to select this instance
122      * @param request The servlet request we are processing
123      */
124     public void reset(ActionMapping mapping, ServletRequest request) {
125         super.reset(mapping, request);
126     }
127 
128     /**
129      * <p>Reset the properties to their <code>initial</code> value if their
130      * <code>reset</code> configuration is set to true or if
131      * <code>reset</code> is set to a list of HTTP request methods that
132      * includes the method of given <code>request</code> object.</p>
133      *
134      * @param mapping The mapping used to select this instance
135      * @param request The servlet request we are processing
136      */
137     public void reset(ActionMapping mapping, HttpServletRequest request) {
138         String name = getDynaClass().getName();
139 
140         if (name == null) {
141             return;
142         }
143 
144         FormBeanConfig config =
145             mapping.getModuleConfig().findFormBeanConfig(name);
146 
147         if (config == null) {
148             return;
149         }
150 
151         // look for properties we should reset
152         FormPropertyConfig[] props = config.findFormPropertyConfigs();
153 
154         for (int i = 0; i < props.length; i++) {
155             String resetValue = props[i].getReset();
156 
157             // skip this property if there's no reset value
158             if ((resetValue == null) || (resetValue.length() <= 0)) {
159                 continue;
160             }
161 
162             boolean reset = Boolean.valueOf(resetValue).booleanValue();
163 
164             if (!reset) {
165                 // check for the request method
166                 // use a StringTokenizer with the default delimiters + a comma
167                 StringTokenizer st =
168                     new StringTokenizer(resetValue, ", \t\n\r\f");
169 
170                 while (st.hasMoreTokens()) {
171                     String token = st.nextToken();
172 
173                     if (token.equalsIgnoreCase(request.getMethod())) {
174                         reset = true;
175 
176                         break;
177                     }
178                 }
179             }
180 
181             if (reset) {
182                 set(props[i].getName(), props[i].initial());
183             }
184         }
185     }
186 
187     // ------------------------------------------------------- DynaBean Methods
188 
189     /**
190      * <p>Indicates if the specified mapped property contain a value for the
191      * specified key value.</p>
192      *
193      * @param name Name of the property to check
194      * @param key  Name of the key to check
195      * @return <code>true</code> if the specified mapped property contains a
196      *         value for the specified key value; <code>true</code>
197      *         otherwise.
198      * @throws NullPointerException     if there is no property of the
199      *                                  specified name
200      * @throws IllegalArgumentException if there is no mapped property of the
201      *                                  specified name
202      */
203     public boolean contains(String name, String key) {
204         Object value = dynaValues.get(name);
205 
206         if (value == null) {
207             throw new NullPointerException("No mapped value for '" + name + "("
208                 + key + ")'");
209         } else if (value instanceof Map) {
210             return (((Map) value).containsKey(key));
211         } else {
212             throw new IllegalArgumentException("Non-mapped property for '"
213                 + name + "(" + key + ")'");
214         }
215     }
216 
217     /**
218      * <p>Return the value of a simple property with the specified name.</p>
219      *
220      * @param name Name of the property whose value is to be retrieved
221      * @return The value of a simple property with the specified name.
222      * @throws IllegalArgumentException if there is no property of the
223      *                                  specified name
224      * @throws NullPointerException     if the type specified for the property
225      *                                  is invalid
226      */
227     public Object get(String name) {
228         // Return any non-null value for the specified property
229         Object value = dynaValues.get(name);
230 
231         if (value != null) {
232             return (value);
233         }
234 
235         // Return a null value for a non-primitive property
236         Class type = getDynaProperty(name).getType();
237 
238         if (type == null) {
239             throw new NullPointerException("The type for property " + name
240                 + " is invalid");
241         }
242 
243         if (!type.isPrimitive()) {
244             return (value);
245         }
246 
247         // Manufacture default values for primitive properties
248         if (type == Boolean.TYPE) {
249             return (Boolean.FALSE);
250         } else if (type == Byte.TYPE) {
251             return (new Byte((byte) 0));
252         } else if (type == Character.TYPE) {
253             return (new Character((char) 0));
254         } else if (type == Double.TYPE) {
255             return (new Double(0.0));
256         } else if (type == Float.TYPE) {
257             return (new Float((float) 0.0));
258         } else if (type == Integer.TYPE) {
259             return (new Integer(0));
260         } else if (type == Long.TYPE) {
261             return (new Long(0));
262         } else if (type == Short.TYPE) {
263             return (new Short((short) 0));
264         } else {
265             return (null);
266         }
267     }
268 
269     /**
270      * <p>Return the value of an indexed property with the specified name.
271      * </p>
272      *
273      * @param name  Name of the property whose value is to be retrieved
274      * @param index Index of the value to be retrieved
275      * @return The value of an indexed property with the specified name.
276      * @throws IllegalArgumentException if there is no property of the
277      *                                  specified name
278      * @throws IllegalArgumentException if the specified property exists, but
279      *                                  is not indexed
280      * @throws NullPointerException     if no array or List has been
281      *                                  initialized for this property
282      */
283     public Object get(String name, int index) {
284         Object value = dynaValues.get(name);
285 
286         if (value == null) {
287             throw new NullPointerException("No indexed value for '" + name
288                 + "[" + index + "]'");
289         } else if (value.getClass().isArray()) {
290             return (Array.get(value, index));
291         } else if (value instanceof List) {
292             return ((List) value).get(index);
293         } else {
294             throw new IllegalArgumentException("Non-indexed property for '"
295                 + name + "[" + index + "]'");
296         }
297     }
298 
299     /**
300      * <p>Return the value of a mapped property with the specified name, or
301      * <code>null</code> if there is no value for the specified key. </p>
302      *
303      * @param name Name of the property whose value is to be retrieved
304      * @param key  Key of the value to be retrieved
305      * @return The value of a mapped property with the specified name, or
306      *         <code>null</code> if there is no value for the specified key.
307      * @throws NullPointerException     if there is no property of the
308      *                                  specified name
309      * @throws IllegalArgumentException if the specified property exists, but
310      *                                  is not mapped
311      */
312     public Object get(String name, String key) {
313         Object value = dynaValues.get(name);
314 
315         if (value == null) {
316             throw new NullPointerException("No mapped value for '" + name + "("
317                 + key + ")'");
318         } else if (value instanceof Map) {
319             return (((Map) value).get(key));
320         } else {
321             throw new IllegalArgumentException("Non-mapped property for '"
322                 + name + "(" + key + ")'");
323         }
324     }
325 
326     /**
327      * <p>Return the value of a <code>String</code> property with the
328      * specified name. This is equivalent to calling <code>(String)
329      * dynaForm.get(name)</code>.</p>
330      *
331      * @param name Name of the property whose value is to be retrieved.
332      * @return The value of a <code>String</code> property with the specified
333      *         name.
334      * @throws IllegalArgumentException if there is no property of the
335      *                                  specified name
336      * @throws NullPointerException     if the type specified for the property
337      *                                  is invalid
338      * @throws ClassCastException       if the property is not a String.
339      * @since Struts 1.2
340      */
341     public String getString(String name) {
342         return (String) this.get(name);
343     }
344 
345     /**
346      * <p>Return the value of a <code>String[]</code> property with the
347      * specified name. This is equivalent to calling <code>(String[])
348      * dynaForm.get(name)</code>.</p>
349      *
350      * @param name Name of the property whose value is to be retrieved.
351      * @return The value of a <code>String[]</code> property with the
352      *         specified name.
353      * @throws IllegalArgumentException if there is no property of the
354      *                                  specified name
355      * @throws NullPointerException     if the type specified for the property
356      *                                  is invalid
357      * @throws ClassCastException       if the property is not a String[].
358      * @since Struts 1.2
359      */
360     public String[] getStrings(String name) {
361         return (String[]) this.get(name);
362     }
363 
364     /**
365      * <p>Return the <code>DynaClass</code> instance that describes the set of
366      * properties available for this <code>DynaBean</code>.</p>
367      *
368      * @return The <code>DynaClass</code> instance that describes the set of
369      *         properties available for this <code>DynaBean</code>.
370      */
371     public DynaClass getDynaClass() {
372         return (this.dynaClass);
373     }
374 
375     /**
376      * <p>Returns the <code>Map</code> containing the property values. This is
377      * done mostly to facilitate accessing the <code>DynaActionForm</code>
378      * through JavaBeans accessors, in order to use the JavaServer Pages
379      * Standard Tag Library (JSTL).</p>
380      *
381      * <p>For instance, the normal JSTL EL syntax for accessing an
382      * <code>ActionForm</code> would be something like this:
383      * <pre>
384      *  ${formbean.prop}</pre>
385      * The JSTL EL syntax for accessing a <code>DynaActionForm</code> looks
386      * something like this (because of the presence of this
387      * <code>getMap()</code> method):
388      * <pre>
389      *  ${dynabean.map.prop}</pre>
390      * </p>
391      *
392      * @return The <code>Map</code> containing the property values.
393      */
394     public Map getMap() {
395         return (dynaValues);
396     }
397 
398     /**
399      * <p>Remove any existing value for the specified key on the specified
400      * mapped property.</p>
401      *
402      * @param name Name of the property for which a value is to be removed
403      * @param key  Key of the value to be removed
404      * @throws NullPointerException     if there is no property of the
405      *                                  specified name
406      * @throws IllegalArgumentException if there is no mapped property of the
407      *                                  specified name
408      */
409     public void remove(String name, String key) {
410         Object value = dynaValues.get(name);
411 
412         if (value == null) {
413             throw new NullPointerException("No mapped value for '" + name + "("
414                 + key + ")'");
415         } else if (value instanceof Map) {
416             ((Map) value).remove(key);
417         } else {
418             throw new IllegalArgumentException("Non-mapped property for '"
419                 + name + "(" + key + ")'");
420         }
421     }
422 
423     /**
424      * <p>Set the value of a simple property with the specified name.</p>
425      *
426      * @param name  Name of the property whose value is to be set
427      * @param value Value to which this property is to be set
428      * @throws ConversionException      if the specified value cannot be
429      *                                  converted to the type required for
430      *                                  this property
431      * @throws IllegalArgumentException if there is no property of the
432      *                                  specified name
433      * @throws NullPointerException     if the type specified for the property
434      *                                  is invalid
435      * @throws NullPointerException     if an attempt is made to set a
436      *                                  primitive property to null
437      */
438     public void set(String name, Object value) {
439         DynaProperty descriptor = getDynaProperty(name);
440 
441         if (descriptor.getType() == null) {
442             throw new NullPointerException("The type for property " + name
443                 + " is invalid");
444         }
445 
446         if (value == null) {
447             if (descriptor.getType().isPrimitive()) {
448                 throw new NullPointerException("Primitive value for '" + name
449                     + "'");
450             }
451         } else if (!isDynaAssignable(descriptor.getType(), value.getClass())) {
452             throw new ConversionException("Cannot assign value of type '"
453                 + value.getClass().getName() + "' to property '" + name
454                 + "' of type '" + descriptor.getType().getName() + "'");
455         }
456 
457         dynaValues.put(name, value);
458     }
459 
460     /**
461      * <p>Set the value of an indexed property with the specified name.</p>
462      *
463      * @param name  Name of the property whose value is to be set
464      * @param index Index of the property to be set
465      * @param value Value to which this property is to be set
466      * @throws ConversionException       if the specified value cannot be
467      *                                   converted to the type required for
468      *                                   this property
469      * @throws NullPointerException      if there is no property of the
470      *                                   specified name
471      * @throws IllegalArgumentException  if the specified property exists, but
472      *                                   is not indexed
473      * @throws IndexOutOfBoundsException if the specified index is outside the
474      *                                   range of the underlying property
475      */
476     public void set(String name, int index, Object value) {
477         Object prop = dynaValues.get(name);
478 
479         if (prop == null) {
480             throw new NullPointerException("No indexed value for '" + name
481                 + "[" + index + "]'");
482         } else if (prop.getClass().isArray()) {
483             Array.set(prop, index, value);
484         } else if (prop instanceof List) {
485             try {
486                 ((List) prop).set(index, value);
487             } catch (ClassCastException e) {
488                 throw new ConversionException(e.getMessage());
489             }
490         } else {
491             throw new IllegalArgumentException("Non-indexed property for '"
492                 + name + "[" + index + "]'");
493         }
494     }
495 
496     /**
497      * <p>Set the value of a mapped property with the specified name.</p>
498      *
499      * @param name  Name of the property whose value is to be set
500      * @param key   Key of the property to be set
501      * @param value Value to which this property is to be set
502      * @throws NullPointerException     if there is no property of the
503      *                                  specified name
504      * @throws IllegalArgumentException if the specified property exists, but
505      *                                  is not mapped
506      */
507     public void set(String name, String key, Object value) {
508         Object prop = dynaValues.get(name);
509 
510         if (prop == null) {
511             throw new NullPointerException("No mapped value for '" + name + "("
512                 + key + ")'");
513         } else if (prop instanceof Map) {
514             ((Map) prop).put(key, value);
515         } else {
516             throw new IllegalArgumentException("Non-mapped property for '"
517                 + name + "(" + key + ")'");
518         }
519     }
520 
521     // --------------------------------------------------------- Public Methods
522 
523     /**
524      * <p>Render a String representation of this object.</p>
525      *
526      * @return A string representation of this object.
527      */
528     public String toString() {
529         StringBuffer sb = new StringBuffer("DynaActionForm[dynaClass=");
530         DynaClass dynaClass = getDynaClass();
531 
532         if (dynaClass == null) {
533             return sb.append("null]").toString();
534         }
535 
536         sb.append(dynaClass.getName());
537 
538         DynaProperty[] props = dynaClass.getDynaProperties();
539 
540         if (props == null) {
541             props = new DynaProperty[0];
542         }
543 
544         for (int i = 0; i < props.length; i++) {
545             sb.append(',');
546             sb.append(props[i].getName());
547             sb.append('=');
548 
549             Object value = get(props[i].getName());
550 
551             if (value == null) {
552                 sb.append("<NULL>");
553             } else if (value.getClass().isArray()) {
554                 int n = Array.getLength(value);
555 
556                 sb.append("{");
557 
558                 for (int j = 0; j < n; j++) {
559                     if (j > 0) {
560                         sb.append(',');
561                     }
562 
563                     sb.append(Array.get(value, j));
564                 }
565 
566                 sb.append("}");
567             } else if (value instanceof List) {
568                 int n = ((List) value).size();
569 
570                 sb.append("{");
571 
572                 for (int j = 0; j < n; j++) {
573                     if (j > 0) {
574                         sb.append(',');
575                     }
576 
577                     sb.append(((List) value).get(j));
578                 }
579 
580                 sb.append("}");
581             } else if (value instanceof Map) {
582                 int n = 0;
583                 Iterator keys = ((Map) value).keySet().iterator();
584 
585                 sb.append("{");
586 
587                 while (keys.hasNext()) {
588                     if (n > 0) {
589                         sb.append(',');
590                     }
591 
592                     n++;
593 
594                     Object key = keys.next();
595 
596                     sb.append(key);
597                     sb.append('=');
598                     sb.append(((Map) value).get(key));
599                 }
600 
601                 sb.append("}");
602             } else {
603                 sb.append(value);
604             }
605         }
606 
607         sb.append("]");
608 
609         return (sb.toString());
610     }
611 
612     // -------------------------------------------------------- Package Methods
613 
614     /**
615      * <p>Set the <code>DynaActionFormClass</code> instance with which we are
616      * associated.</p>
617      *
618      * @param dynaClass The DynaActionFormClass instance for this bean
619      */
620     void setDynaActionFormClass(DynaActionFormClass dynaClass) {
621         this.dynaClass = dynaClass;
622     }
623 
624     // ------------------------------------------------------ Protected Methods
625 
626     /**
627      * <p>Return the property descriptor for the specified property name.</p>
628      *
629      * @param name Name of the property for which to retrieve the descriptor
630      * @return The property descriptor for the specified property name.
631      * @throws IllegalArgumentException if this is not a valid property name
632      *                                  for our DynaClass
633      */
634     protected DynaProperty getDynaProperty(String name) {
635         DynaProperty descriptor = getDynaClass().getDynaProperty(name);
636 
637         if (descriptor == null) {
638             throw new IllegalArgumentException("Invalid property name '" + name
639                 + "'");
640         }
641 
642         return (descriptor);
643     }
644 
645     /**
646      * <p>Indicates if an object of the source class is assignable to the
647      * destination class.</p>
648      *
649      * @param dest   Destination class
650      * @param source Source class
651      * @return <code>true</code> if the source is assignable to the
652      *         destination; <code>false</code> otherwise.
653      */
654     protected boolean isDynaAssignable(Class dest, Class source) {
655         if (dest.isAssignableFrom(source)
656             || ((dest == Boolean.TYPE) && (source == Boolean.class))
657             || ((dest == Byte.TYPE) && (source == Byte.class))
658             || ((dest == Character.TYPE) && (source == Character.class))
659             || ((dest == Double.TYPE) && (source == Double.class))
660             || ((dest == Float.TYPE) && (source == Float.class))
661             || ((dest == Integer.TYPE) && (source == Integer.class))
662             || ((dest == Long.TYPE) && (source == Long.class))
663             || ((dest == Short.TYPE) && (source == Short.class))) {
664             return (true);
665         } else {
666             return (false);
667         }
668     }
669 }