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
DataEngine dteDataEngine = getDataEngine( );
				IDataEngine dataEngine = executionContext.getDataEngine( );
				dataEngine.defineDataSet( dataSet );
				QueryDefinition queryDefn = new QueryDefinition( );
				queryDefn.setDataSetName( dataSet.getQualifiedName( ) );
				SlotHandle parameters = parameterGroup.getParameters( );
				Iterator iter = parameters.iterator( );
/*				if ( labelMap == null )
					labelMap = new HashMap( );
				if ( valueMap == null )
					valueMap = new HashMap( );*/
				
				if ( labelColumnBindingNames == null )
					labelColumnBindingNames = new ArrayList();
				
				while ( iter.hasNext( ) )
				{
					Object param = iter.next( );
					if ( param instanceof ScalarParameterHandle )
					{
						String valueExpString = ( (ScalarParameterHandle) param )
								.getValueExpr( );
						ScriptExpression valueExpObject = new ScriptExpression(
								valueExpString );
						
						String keyValue = VALUE_PREFIX+parameterGroup.getName( ) + "_"
						+ ( (ScalarParameterHandle) param ).getName( );
						
	/*					valueMap.put( keyValue,
								valueExpObject );*/