<data-mart-data-source name="Data Source" id="4">
<property name="datamartURL">include</property>
<property name="accessType">transient</property>
import org.eclipse.birt.report.model.api.elements.DesignChoiceConstants;
DesignConfig config = new DesignConfig( );
config.setBIRTHome( BIRT_HOME );
DesignEngine engine = new DesignEngine( config );
SessionHandle sessionHandle = engine.newSessionHandle( ULocale.ENGLISH );
ReportDesignHandle designHandle = sessionHandle.createDesign();
ElementFactory factory = designHandle.getElementFactory( );
DataMartDataSourceHandle dataSource =factory.newDataMartDataSource( "Data Source" );
dataSource.setDataMartURL( "include" );
dataSource.setAccessType( DesignChoiceConstants.ACCESS_TYPE_TRANSIENT );
designHandle.getDataSources( ).add( dataSource );
FileOutputStream fos = new FileOutputStream("test.rptdesign");
designHandle.serialize( fos );
System.out.println("Done");