Expression.getFunctionWithArguments() adds additional empty argument...

Question

Hi; I'm trying to use the Expression.getFunctionWithArguments() method to include the Oracle db function bitand() in a query. It seems that getFunctionWithArguments() always includes an extra ',' at the front of the argument list, here's an example of the SQL that is created;
SELECT t0.CLASS_NAME, t0.DESCRIPTION, t0.EDITABLE,
t0.ID, t0.DATE_MODIFIED, t0.DATE_CREATED, t0.MODIFIED_BY,
t0.ACL_ID, t0.NAME, t0.CREATED_BY, t0.TYPE_ID, t0.WKSP_ID,
t1.ID, t1.NAME
FROM XDOOBJECT t0, ALL_OBJECT_PRIVILEGES t2, ACL t1
WHERE (((t1.ID = t2.xdoobject_id)
AND ((t2.user_id = 'twatson2')
AND (bitand(, t2.privilege, 2) = 2)))
AND ((t1.ID = t0.ID)
AND (t0.CLASS_NAME = 'oracle.xdo.server.security.authorization.model.ACL')))
Notice the "AND (bitand(, t2.privilege, 2) = 2)))"
Here's my code that sets up this portion of the expression;
Expression exp1 = parentEb.getTable("ALL_OBJECT_PRIVILEGES")
.getField("xdoobject_id");
Expression exp2 = parentEb.getTable("ALL_OBJECT_PRIVILEGES")
.getField("user_id");
Expression exp3 = parentEb.getTable("ALL_OBJECT_PRIVILEGES").getField("privilege");
Vector args = new Vector();
args.add(exp3);
args.add(READ_PRIVILEGE_VALUE);
Expression exp4 = parentEb.getFunctionWithArguments("bitand",args).equal(READ_PRIVILEGE_VALUE);
Expression exp = parentEb.get("ID").equal(exp1)
.and(exp2.equal(userId).and(exp4));
I've tried adding additional arguments to the Vector just to see what it does and it always has the extra empty argument.
Thanks for you help with this.
-Tim Watson

Answer 1

Hi Tim,
It seems this method requires a base, which is t2.privilege in your case. You need to call getFunctionWithArguments() on the base. So your code should be something like:
Expression exp3 = parentEb.getTable("ALL_OBJECT_PRIVILEGES").getField("privilege");
Vector args = new Vector();
args.add(READ_PRIVILEGE_VALUE);
Expression exp4 = exp3.getFunctionWithArguments("bitand",args).equal(READ_PRIVILEGE_VALUE);
Shannon