Oracle9iAS Portal Developer Kit

Scoping parameters

This topic explains how to use scoped names with the parameters in the wwpro_api_parameters API package.

As the portlet reference path uniquely identifies a portlet instance on a page, it provides the scoping information for the parameters in this package and can be used to target parameters to individual portlets or groups of portlets on a given page.

Example:

If portlets named 'a' and 'b' are displayed on a given page, and if the following parameters are passed to the portlets through the URL:

  • deptno = 10

  • a.deptno = 20 - where 'a' is the reference path
  • a.empno = 30 - where 'a' is the reference path

then these results are returned for the calls to the get_value API:

  • wwpro_api_parameter.get_value('deptno','a') returns 20

  • wwpro_api_parameter.get_value('deptno','b') returns 10
  • wwpro_api_parameter.get_value('empno','b') returns an empty list

Comments:

  • Parameter values found at a tighter scope replace values at a looser scope. A tightly scoped parameter is one that is fully specified. An example for the deptno parameter is <referencepath>.deptno. An example of a loosely scoped parameter is deptno without a reference path.

  • If the URL contains both types of parameters and if the requester uses a reference path, the parameter at the tighter of the two bindings (i.e., <referencepath>.deptno) is returned.

  • In the first example call, the result is '20' because in the URL the parameter is fully specified as a.deptno and the value is set to '20'.

  • In the second example call, there is no parameter deptno specified for portlet with reference path 'b', so the parameter is checked at a looser (global) scope. The value of deptno at the looser scope is '10', so the result is '10'.

  • In the third example call, there is no empno parameter with reference path 'b' specified for portlet . Even if a check is done one level up at a looser (global) scope, there is no such parameter, so the API returns an empty list.

Related topics

The PL/SQL API Reference is part of the Portal Developer Kit on Portal Studio