@Converter

Use the @Converter annotation to specify a custom converter for modification of the data value(s) during the reading and writing of a mapped attribute.

Annotation Elements

Table 2-15 describes this annotation's elements.

Table 2-15 @Converter Annotation Elements

Annotation Element	Description	Default
`name`	The `String` name for your converter, must be unique across the persistence unit	none
`converterClass`	The class of your converter. This class must implement the `org.eclipse.persistence.mappings.converters.Converter` interface.	none

Usage

Use @Converter to define a named converter that can be used with mappings. A converter can be defined on an entity class, method, or field. Specify a converter with the @Convert annotation on a Basic or ElementCollection mapping.

Using non-JPA Converter Annotations

EclipseLink provides a set of non-JPA converter annotations (in addition to the JPA default type mappings):

The persistence provider searches the converter annotations in the following order:

@Convert
@Enumerated
@Lob
@Temporal
Serialized (automatic)

Specify the converters on the following classes:

@Entity
@MappedSuperclass
@Embeddable

Use the converters with the following mappings:

@Basic
@Id
@Version
@ElementCollection

An exception is thrown if a converter is specified with any other type of mapping annotation.

Examples

Example 2-32 shows how to use the @Converter annotation to specify a converter class for the gender field.

Example 2-32 Using the @Converter Annotation

@Entity
 public class Employee implements Serializable{
    ...
     @Basic
     @Converter (
         name="genderConverter",
         converterClass=org.myorg.converters.GenderConverter.class
     )
     @Convert("genderConverter")
     public String getGender() {
         return gender;
     }
     ...
 }

Example 2-33 shows how to use the <converter> element in the eclipselink-orm.xml file.

Example 2-33 Using <converter> XML

<entity class="Employee">
...
    <attributes>
    ...
      <basic name="gender">
        <convert>genderConverter</convert>
        <converter name="genderConverter" class="org.myorg.converters.GenderConverter"/>
      </basic>
    ...
    </attributes>
</entity>

See Also

For more information, see:

"@Converters"
"@Convert"
"@MapKeyConvert"
Understanding EclipseLink