Revision as of 14:20, 18 June 2010

EclipseLink
Website
Download
Community
Mailing List • Forums • IRC • mattermost
Issues
Open • Help Wanted • Bug Day
Contribute
Browse Source

Key API {{{apis}}}

@TypeConverter Annotation and <type-converter> XML

The @TypeConverter is an EclipseLink-specific annotation. You can use it to specify an org.eclipse.persistence.mappings.converters.TypeConversionConverter for modification of the data value(s) during the reading and writing of a mapped attribute.

 
 @Target({TYPE, METHOD, FIELD})
 @Retention(RUNTIME)
 public @interface TypeConverter {
    String name();
    Class dataType() default void.class;
    Class objectType() default void.class;
 }

¹ The default is inferred from the type of the persistence field or property.

This example shows how to use the @TypeConverter annotation to convert the Double value stored in the database to a Float value stored in the entity.

Usage of the @TypeConverter Annotation

 @Entity
 public class Employee implements Serializable{
     ...
     @TypeConverter (
         name="doubleToFloat",
         dataType=Double.class,
         objectType=Float.class,
     )
     @Convert("doubleToFloat")
     public Number getGradePointAverage() {
         return gradePointAverage;
     }
     ...
 }

Converter	Default Conversions and Converters	ObjectType Conveter
EclipseLink Home JPA User Guide: Table of Contents, Search
How to contribute to this guide...