Bug 212375 [Automation][Regression]Exception occurs when preview a outputParams["xxx"]
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedDataSourceQuery.java
appContext );
		logger.exiting( PreparedDataSourceQuery.class.getName( ),
				"PreparedDataSourceQuery" );
	}
	
	/*
	 * @see org.eclipse.birt.data.engine.api.IPreparedQuery#getReportQueryDefn()
	 */
	public IQueryDefinition getReportQueryDefn()
	{
		return this.queryDefn;
	}
	
	/*
	 * @see org.eclipse.birt.data.engine.impl.IPreparedQueryService#getDataSourceQuery()
	 */
	public PreparedDataSourceQuery getDataSourceQuery( )
	{
		return this;
	}
	
	/**
	 * Executes the prepared execution plan.  This returns
	 * a QueryResult object at a state ready to return its 
	 * current result iterator, or evaluate an aggregate expression.
	 * <p>
	 * This includes setup runtime state, and evaluation of
	 * any beforeOpen and afterOpen scripts on a data set. 
	 * @return The QueryResults object opened and ready to return
	 * 		the results of a report query.