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1   /*
2    * Copyright 2005 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  
17  package org.apache.jdo.impl.model.jdo;
18  
19  import org.apache.jdo.impl.model.jdo.util.TypeSupport;
20  import org.apache.jdo.model.ModelFatalException;
21  import org.apache.jdo.model.java.JavaType;
22  import org.apache.jdo.model.jdo.JDOClass;
23  import org.apache.jdo.model.jdo.JDOField;
24  import org.apache.jdo.model.jdo.JDOMap;
25  import org.apache.jdo.model.jdo.JDOModel;
26  import org.apache.jdo.util.I18NHelper;
27  
28  /***
29   * An instance of this class represents the JDO relationship metadata 
30   * (the treatment of keys and values) of a map relationship field. 
31   * This dynamic implementation only stores property values explicitly
32   * set by setter method.
33   *
34   * @author Michael Bouschen
35   * @since 1.1
36   * @version 1.1
37   */
38  public class JDOMapImplDynamic extends JDORelationshipImpl implements JDOMap {
39      
40      /*** Property embeddedKey. */
41      protected Boolean embeddedKey;
42  
43      /*** Property keyType. No default. */
44      protected transient JavaType keyType;
45  
46      /*** Property keyTypeName. Defaults to java.lang.Object. */
47      private String keyTypeName = "java.lang.Object"; //NOI18N
48  
49      /*** Property embeddedValue. */
50      protected Boolean embeddedValue;
51  
52      /*** Property valueType. No default. */
53      protected transient JavaType valueType;
54  
55      /*** Property valueTypeName. Defaults to java.lang.Object. */
56      private String valueTypeName = "java.lang.Object"; //NOI18N
57  
58      /*** I18N support */
59      private final static I18NHelper msg =  
60          I18NHelper.getInstance(JDOMapImplDynamic.class);
61  
62      /***
63       * Determines whether the keys of the map should be stored if possible as 
64       * part of the instance instead of as their own instances in the datastore.
65       * @return <code>true</code> if the keys are stored as part of this instance;
66       * <code>false</code> otherwise
67       */
68      public boolean isEmbeddedKey() {
69          if (embeddedKey != null) {
70              // return embeddedKey, if explicitly set by the setter
71              return embeddedKey.booleanValue();
72          }
73          
74          // not set => calculate
75          JavaType type = getKeyType();
76          return (type != null) ? 
77              TypeSupport.isEmbeddedElementType(type) : false;
78      }
79      
80      /***
81       * Set whether the keys of the map should be stored if possible as part 
82       * of the instance instead of as their own instances in the datastore.
83       * @param embeddedKey <code>true</code> if the keys are stored as part of
84       * this instance; <code>false</code> otherwise
85       */
86      public void setEmbeddedKey(boolean embeddedKey) {
87          this.embeddedKey = (embeddedKey ? Boolean.TRUE : Boolean.FALSE);
88      }
89  
90      /***
91       * Get the type representation of the keys for this JDOMap.
92       * @return the type of the keys of this JDOMap  
93       */
94      public JavaType getKeyType() {
95          if (keyType != null) {
96              // return keyType, if explicitly set by the setter
97              return keyType;
98          }
99      
100         // not set => calculate
101         JavaType type = null;
102         if (keyTypeName != null) {
103             JDOField jdoField = getDeclaringField();
104             JDOClass jdoClass = jdoField.getDeclaringClass();
105             JDOModel jdoModel = jdoClass.getDeclaringModel();
106             type = TypeSupport.resolveType(jdoModel, keyTypeName,
107                                            jdoClass.getPackagePrefix());
108             if (type == null) {
109                 throw new ModelFatalException(
110                     msg.msg("EXC_CannotResolveKeyType", keyTypeName, //NOI18N
111                             jdoField.getName(), jdoClass.getName()));
112             }
113         }
114         
115         return type;
116     }
117 
118     /***
119      * Set the type representation of the keys for this JDOMap.
120      * @param keyType the type representation of the keys
121      */
122     public void setKeyType(JavaType keyType) {
123         this.keyType = keyType;
124         if (keyType != null) {
125             setKeyTypeName(keyType.getName());
126         }
127     }
128 
129     /***
130      * Get the string representation of the type of the keys for this JDOMap.
131      * @return the key type as string
132      */
133     public String getKeyTypeName() {
134         return keyTypeName;
135     }
136 
137     /***
138      * Set string representation of the type of the keys for this JDOMap.
139      * @param keyTypeName the name of the key type
140      */
141     public void setKeyTypeName(String keyTypeName) {
142         this.keyTypeName = keyTypeName;
143     }
144 
145     /***
146      * Determines whether the values of the map should be stored if possible as 
147      * part of the instance instead of as their own instances in the datastore.
148      * @return <code>true</code> if the values are stored as part of this 
149      * instance; <code>false</code> otherwise
150      */
151     public boolean isEmbeddedValue() {
152         if (embeddedValue != null) {
153             // return embeddedKey, if explicitly set by the setter
154             return embeddedValue.booleanValue();
155         }
156         
157         // not set => calculate
158         JavaType type = getValueType();
159         return (type != null) ? 
160             TypeSupport.isEmbeddedElementType(type) : false;
161     }
162     
163     /***
164      * Set whether the values of the map should be stored if possible as part 
165      * of the instance instead of as their own instances in the datastore.
166      * @param embeddedValue <code>true</code> if the values are stored as part 
167      * of this instance; <code>false</code> otherwise
168      */
169     public void setEmbeddedValue(boolean embeddedValue) {
170         this.embeddedValue = (embeddedValue ? Boolean.TRUE : Boolean.FALSE);
171     }
172 
173     /***
174      * Get the type representation of the values for this JDOMap.
175      * @return the type of the values of this JDOMap  
176      */
177     public JavaType getValueType() {
178         if (valueType != null) {
179             // return valueType, if explicitly set by the setter
180             return valueType;
181         }
182     
183         // not set => calculate
184         JavaType type = null;
185         if (valueTypeName != null) {
186             JDOField jdoField = getDeclaringField();
187             JDOClass jdoClass = jdoField.getDeclaringClass();
188             JDOModel jdoModel = jdoClass.getDeclaringModel();
189             type = TypeSupport.resolveType(jdoModel, valueTypeName,
190                                            jdoClass.getPackagePrefix());
191             if (type == null) {
192                 throw new ModelFatalException(
193                     msg.msg("EXC_CannotResolveValueType", valueTypeName, //NOI18N
194                             jdoField.getName(), jdoClass.getName()));
195             }
196         }
197         
198         return type;
199     }
200 
201     /***
202      * Set the type representation of the values for this JDOMap.
203      * @param valueType the type representation of the values
204      */
205     public void setValueType(JavaType valueType) {
206         this.valueType = valueType;
207         if (valueType != null) {
208             setKeyTypeName(valueType.getName());
209         }
210     }
211 
212     /***
213      * Get the string representation of the type of the values for this JDOMap.
214      * @return the key value as string
215      */
216     public String getValueTypeName() {
217         return valueTypeName;
218     }
219 
220     /***
221      * Set string representation of the type of the values for this JDOMap.
222      * @param valueTypeName the name of the value type
223      */
224     public void setValueTypeName(String valueTypeName) {
225         this.valueTypeName = valueTypeName;
226     }
227 
228     /***
229      * Determines whether this JDORelationship represents a map 
230      * relationship or not. A return of <code>true</code> means this
231      * JDORelationship is a JDOMap instance.
232      * @return <code>true</code> if this JDORelationship represents a
233      * map relationship; <code>false</code> otherwise.
234      */
235     public boolean isJDOMap() {
236         return true;
237     }
238 
239     //========= Internal helper methods ==========
240 
241     /*** 
242      * Get the type representation of the relationship. This will be 
243      * the JavaType for references, the element type for collections
244      * and arrays, and the value type for maps.
245      * @return the relationship type
246      */
247     public JavaType getRelatedJavaType() {
248         return getValueType();
249     }
250 
251 }