Converters and composers
Converters and composers are used to perform the mapping operation between an entity attribute and one or more table columns:
A converter maps one attribute to one column. Many converters are provided to convert SQL data into Java types, but you can write your own as well. A converter is specified in the mapping editor and is used for simple mapping.
A composer maps one attribute (which can be a complex class) to multiple table columns. A composer is specified in the mapping editor and is used for complex mapping.
The mapping editor allows you to specify a “complex mapping” for a CMP field. When you use this option, you have to provide a composer class. You typically use this option for complex attributes, such as the ...