Bug 151694 appContext is null when evaluating parameters
On a report with parameters, during the resolution of the report parameters, datasource used to populate values of each parameters doesn't have any appContext. We used a jdbcbridbe, and thru appContext, we're retrieving jndi name and others parameters usueful for our datasource. In those case, during the evaluation of parameters, appContext is null so the datasource used to populate values of the parameters are not from the same database ...
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
return;
			}
			catch ( BirtException ex )
			{
				ex.printStackTrace( );
			}
		}
		dataCache.put( parameterGroup.getName( ), null );
	}
	/**
	 * The second step to work with the cascading parameters. Get the selection
	 * choices for a parameter in the cascading group. The parameter to work on
	 * is the parameter on the next level in the parameter cascading hierarchy.
	 * For the "parameter to work on", please see the following example. Assume
	 * we have a cascading parameter group as Country - State - City. If user
	 * specified an empty array in groupKeyValues (meaning user doesn't have any
	 * parameter value), the parameter to work on will be the first level which
	 * is Country in this case. If user specified groupKeyValues as
	 * Object[]{"USA"} (meaning user has set the value of the top level), the
	 * parameter to work on will be the second level which is State in "USA" in
	 * this case. If user specified groupKeyValues as Object[]{"USA", "CA"}
	 * (meaning user has set the values of the top and the second level), the
	 * parameter to work on will be the third level which is City in "USA, CA"
	 * in this case.
	 * 
	 * @param parameterGroupName -
	 *            the cascading parameter group name
	 * @param groupKeyValues -
	 *            the array of known parameter values (see the example above)
	 * @return the selection list of the parameter to work on