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Java > Open Source Codes > org > apache > cayenne > access > types > EnumTypeFactory


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19 package org.apache.cayenne.access.types;
20
21 import java.lang.reflect.Constructor JavaDoc;
22
23 import org.apache.cayenne.util.Util;
24
25 /**
26  * ExtendedTypeFactory for handling JDK 1.5 Enums. Gracefully handles JDK 1.4 environment.
27  *
28  * @since 3.0
29  * @author Andrus Adamchik
30  */

31 class EnumTypeFactory implements ExtendedTypeFactory {
32
33     private Constructor JavaDoc enumTypeConstructor;
34
35     EnumTypeFactory() {
36
37         // see if we can support enums
38
try {
39             Class JavaDoc enumTypeClass = Util
40                     .getJavaClass("org.apache.cayenne.access.types.EnumType");
41             enumTypeConstructor = enumTypeClass.getConstructor(new Class JavaDoc[] {
42                 Class JavaDoc.class
43             });
44         }
45         catch (Throwable JavaDoc th) {
46             // no enums support... either Java 1.4 or Cayenne 1.5 extensions are absent
47
}
48     }
49
50     public ExtendedType getType(Class JavaDoc objectClass) {
51         if (enumTypeConstructor == null) {
52             return null;
53         }
54
55         try {
56             // load EnumType via reflection as the source has to stay JDK 1.4 compliant
57
ExtendedType type = (ExtendedType) enumTypeConstructor
58                     .newInstance(new Object JavaDoc[] {
59                         objectClass
60                     });
61
62             return type;
63         }
64         catch (Throwable JavaDoc th) {
65             // ignore exceptions...
66
return null;
67         }
68     }
69 }
70
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