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31.13.4. User Type Mappings
User type mappings allow one to map from JDBC column types to custom CMP fields types by specifying an instance of
org.jboss.ejb.plugins.cmp.jdbc.Mapper
interface, the definition of which is shown below.
A prototypical use case is the mapping of an integer type to its type-safe Java enumeration instance. The content model of the
user-type-mappings
element consists of one or more user-type-mapping
elements, the content model of which is shown in Figure 31.20, “The user-type-mapping content model >”.
Figure 31.20. The user-type-mapping content model >
- java-type: the fully qualified name of the CMP field type in the mapping.
- mapped-type: the fully qualified name of the database type in the mapping.
- mapper: the fully qualified name of the
Mapper
interface implementation that handles the conversion between thejava-type
andmapped-type
.