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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  package org.apache.jdo.impl.model.jdo;
19  
20  import org.apache.jdo.model.ModelException;
21  import org.apache.jdo.model.java.JavaField;
22  import org.apache.jdo.model.java.JavaProperty;
23  import org.apache.jdo.model.java.JavaType;
24  import org.apache.jdo.model.jdo.JDOClass;
25  import org.apache.jdo.model.jdo.JDOField;
26  import org.apache.jdo.model.jdo.JDOProperty;
27  
28  /***
29   * An instance of this class represents the JDO metadata of a managed property
30   * of a persistence capable class. This dynamic implementation only
31   * stores values explicitly set by setter method. 
32   *
33   * @author Michael Bouschen
34   * @since 2.0
35   * @version 2.0
36   */
37  public class JDOPropertyImplDynamic
38      extends JDOFieldImplDynamic
39      implements JDOProperty
40  {
41      /*** Constructor. */
42      protected JDOPropertyImplDynamic(String name, JDOClass declaringClass) {
43          super(name, declaringClass);
44      }
45  
46      // ===== methods specified in JDOField =====
47  
48      /***
49       * Get the corresponding JavaField representation for this JDOProperty.
50       * @return the corresponding JavaProperty representation
51       */
52      public JavaField getJavaField() {
53          if (javaField != null) {
54              // return java field, if explicitly set by the setter
55              return javaField;
56          }
57          
58          // not set => calculate
59          JavaType javaType = getDeclaringClass().getJavaType();
60          return javaType.getJavaProperty(getName());
61      }
62  
63      /***
64       * Sets the corresponding JavaProperty representation for this JDOProperty.
65       * @param javaField the corresponding JavaProperty representation
66       * @throws ModelException if impossible
67       */
68      public void setJavaField(JavaField javaField) throws ModelException {
69          if (javaField instanceof JavaProperty) {
70              this.javaField = javaField;
71          }
72          else {
73              throw new ModelException(msg.msg(
74                  "EXC_InvalidJavaFieldForJDOProperty", javaField)); //NOI18N
75          }
76      }
77  
78      /***
79       * Convenience method to check whether this field represents a property.
80       * @return <code>true</code> if this field represents a property; 
81       * <code>false</code> otherwise
82       */
83      public boolean isProperty() {
84          return true;
85      }
86  
87      // ===== methods specified in JDOProperty =====
88  
89      /*** 
90       * Return the JDOField instance associated with this property, if
91       * available. If there is no JDOField instance associated, then the method
92       * returns <code>null</code>.
93       * <p>
94       * This implementation always retruns <code>null</code>.
95       * @return associated JDOField instance or <code>null</code> if not
96       * available.
97       */
98      public JDOField getAssociatedJDOField() {
99          return null;
100     }
101 }