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DeptBean

...

This is a cmp field.

id

Notice that with the ejb.persistent field you do not specify the name of the field. Thus if

you changed the names of the CMP field, that is,

getTheID

,

setTheID

, you would

not have to manually sync the deployment descriptor. This is the beauty of XDoclet; it

knows about the context of the declaration. These are the features that make

refactoring code easier.

XDoclet and EJB technology: Set the vendor specific

OR mapping with the vendor specific tag (or not)

The

ejb.persistence

tag allows you to specify the mapping from a cmp field to a

table column. Here is an example of using the

ejb.persistence

tag with the

DeptBean

 s ID CMP field as follows:

/**

* This is a cmp field. The cmp field is read only.

* And it is the primary key.

*

* @ejb.pk field

* @ejb.persistent field

* @ejb.interface method view type="local"

* @ejb.persistence

column name="DEPTID"

* @resin ejb.cmp field

sql column="DEPTID"

*/

public abstract Integer getId();

public abstract void setId(Integer id);

Notice that the above ejb.persistence maps the ID CMP field to the DEPTID column.

(In this example I also use the vendor specific mapping tag since not all vendor

templates support the new

ejb.persistence

tag yet). The above XDoclet tags

would generate the following mappings in the vendor specific RDBMS mapping files.

Resin s resin.ejb

Page 36 of 49

Enhance J2EE component reuse with XDoclets