Creating Named Query: from OracleCallableStatement

Question

We have a great many PL/SQL Procs in an existing legacy system that return PL/SQL Boolean, that we wish to call from toplink.
Ideally we would like to create Toplink Nameded queries that wrap the SQL call statements.
Does anyone know if its possible to convert a call like the following into a Toplink named query?
String domain = "COST CENTRE";
String value = "OP";
OracleCallableStatement xcall = (OracleCallableStatement) con.prepareCall(
"BEGIN ? := SYS.SQLJUTL.bool2int(is_valid_value(?, ?)); END;");
xcall.registerOutParameter( 1, OracleTypes.INTEGER);
xcall.setString(2,domain);
xcall.setString(3,value);
xcall.execute();
System.out.println ("Status = " + xcall.getInt(1));
FUNCTION is_valid_value(
p_rv_domain IN CG_REF_CODES.RV_DOMAIN%TYPE,
p_rv_low_value IN CG_REF_CODES.RV_LOW_VALUE%TYPE
RETURN BOOLEAN
IS
Many thanks,
Lee.

Answer 1

You can define Stored Procedure calls in TopLink through the StoredProcedureCall class. StoredProcedureCall allows you to define output parameters to access return values.
Example:
StoredProcedureCall call = new StoredProcedureCall();
call.setProcedureName("is_valid_value");
call.addNamedArgumentValue("DOMAIN", domain);
call.addNamedArgumentValue("VALUE", value);
call.addNamedOutputArgument("RESULT", "RESULT", Integer.class);
List results = session.executeSelectingCall(call);
boolean value = ((Integer) ((Map) results.get(0)).get("RESULT")).intValue() == 0;
However what you seem to be accessing is a stored function, not a procedure. To access a stored function from TopLink you must use an SQLCall and select the return value through the DUAL table.
Example:
SQLCall call = new SQLCall("Select SYS.SQLJUTL.bool2int(is_valid_value(" + domain + ", " + value + ")) from dual");
List results = session.executeSelectingCall(call);