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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.myfaces.orchestra.dynaForm.metadata.impl.jsf;
20  
21  import java.util.Iterator;
22  
23  import org.apache.myfaces.orchestra.dynaForm.jsf.component.DynaConfig;
24  import org.apache.myfaces.orchestra.dynaForm.jsf.component.DynaConfigs;
25  import org.apache.myfaces.orchestra.dynaForm.jsf.component.DynaForm;
26  import org.apache.myfaces.orchestra.dynaForm.metadata.Extractor;
27  import org.apache.myfaces.orchestra.dynaForm.metadata.MetaDataWritable;
28  import org.apache.myfaces.orchestra.dynaForm.metadata.MetaFieldWritable;
29  
30  /**
31   * Extract metadata from a DynaForm UIComponent.
32   * <p>
33   * This looks for child DynaConfig components attached to the DynaForm and merges
34   * any overrides they declare with the current values of a MetaData object. This
35   * allows basic information about an entity to be determined by other means, then
36   * for any components attached to the DynaForm component to override those settings.
37   */
38  public abstract class AbstractJsfExtractor implements Extractor
39  {
40      public AbstractJsfExtractor()
41      {
42      }
43  
44      /**
45       * Copy metadata overrides attached to a DynaForm UIComponent into an 
46       * existing MetaData instance.
47       * <p>
48       * The specified entity must be an instance of DynaForm (a JSF UIComponent).
49       */
50      public void getMetaData(MetaDataWritable metaData, Object entity)
51      {
52          if (!(entity instanceof DynaForm))
53          {
54              throw new IllegalArgumentException("passed entity argument not a DynaForm: " + entity);
55          }
56  
57          create(metaData, (DynaForm) entity);
58      }
59  
60      /**
61       * create the metadata out of the dynaConfigs for the given component
62       */
63      @SuppressWarnings("unchecked")
64      protected void create(MetaDataWritable metaData, DynaForm dynaForm)
65      {
66          DynaConfigs formConfig = dynaForm.getFormConfigs();
67          if (formConfig == null)
68          {
69              return;
70          }
71  
72          Iterator<DynaConfig> entries = formConfig.iterator();
73          while (entries.hasNext())
74          {
75              DynaConfig dynaConfig = entries.next();
76              String name = dynaConfig.getFor();
77              if (name == null)
78              {
79                  throw new IllegalArgumentException("'for' in config tag required");
80              }
81  
82              if (metaData.isWantedField(name))
83              {
84                  MetaFieldWritable field = metaData.getOrCreateField(name);
85  
86                  initFromConfig(field, dynaConfig);
87              }
88          }
89      }
90  
91      protected abstract void initFromConfig(MetaFieldWritable field, DynaConfig config);
92  }