JDBC Developer's Guide - Supra - Cincom

Controlling when custom mapping occursOnce your Java application has a database object reference, there are severalmethods to materialize the referenced database object as an instance of thecustom mapped class:The java.sql.ResultSet.getObject method♦♦The ordbObject.getObject methodThe getAttributes method of the java.sql.Struct interfaceUsing the java.sql.ResultSet.getObject MethodThe generic JDBC way to request custom mapping is to use the getObjectmethod of the java.sql.ResultSet interface.The Cincom ORDB JDBC driver performs custom mapping when the getObject()method invokes the ResultSet column that contains an object reference. Usethe getRef() method if you do not want custom mapping performed.The following example assumes that the default type map associates thedatabase class “seashore” with the java class jseashore:...ResultSet rset = stmt.executeQuery ("SELECT name,beach FROM resortWHERE beach IS NOT NULL");// get the beach as an instance of the custom mapped class// jseashore.javajseashore beach = null;while (rset.next ()) {beach = (jseashore)rset.getObject(2));// Internally the JDBC Driver performs these actions:// 1. If the database value is NOT an oid, then// generate a java object of appropriate type and// return.// 2. The database value is an oid, what we really have is// an instance of the ordbObject class.// 3. Check the type map (default or passed as parm) to see// if the database class has a custom java class.// If there is no custom class, return the ordbObject// to application as a (by casting to) java.sql.Struct// 4. If there is a custom map, instantiate an instance of theJDBC Developer's Guide, P25-9504-03 Page 50Chapter: 4. Cincom ORDB ExtensionsSection: Creating custom Java classes for Cincom ORDB objects