Use the Enterprise JavaBeans data mediator service for data access
Overview
The following steps use code samples to describe a simple instance of how to create the Enterprise JavaBeans data mediator service (DMS) metadata.
Procedure
- A mediator instance is created using one of the create methods on the mediator factory (com.ibm.websphere.sdo.mediator.ejb.MediatorFactory) as in the following example
import com.ibm.websphere.sdo.mediator.ejb.Mediator; import com.ibm.websphere.sdo.mediator.ejb.MediatorFactory; import com.ibm.webpshere.ejbquery.QueryException; import commonj.sdo.DataObject; try{ String[] query = { "select d.deptno,d.name from DeptBean as d" }; Mediator m = MediatorFactory.getInstance().createMediator( query, null); DataObject root = m.getGraph(); } catch (QueryException e) { ... }- There are 3 different forms of the createMediator method. The arguments are explained below.
createMediator( query, parms) createMediator( query, parms, schema ) createMediator( query, parms, schema, typeMap, pattern)The arguments to the createMediator method are:
String query array of EJB query statements Object parms values for input parameters of the query statements Eclass* schema the EClass of the root DataObject Map* typeMap a java.util.Map that maps EJB Abstract Schema Names from the query statement into Eclass names int* pattern the pattern used for containment * used only when using caller provided schema
See Also
Enterprise JavaBeans Data Mediator Service
See Also
DataGraph schema
Example: EJB mediator query arguments