Bug 201396 Exception is thrown out when a chart use the list shared result set [0005]
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/QueryResults.java
* @see org.eclipse.birt.data.engine.api.IQueryResults#getPreparedQuery()
	 */
	public IPreparedQuery getPreparedQuery()
	{ 
		return queryService.getPreparedQuery( );
	}
	
	/*
	 * @see org.eclipse.birt.data.engine.api.IQueryResults#getResultMetaData()
	 */
	public IResultMetaData getResultMetaData( ) throws DataException
	{
		if ( queryService == null )
			throw new DataException( ResourceConstants.RESULT_CLOSED );
		
		try
		{
			return queryService.getResultMetaData( );
		}
		catch ( DataException e )
		{
			throw e;
		}
	}
	
	/*
	 * 
	 * Returns the current result's iterator. Repeated call of this method
	 * without having advanced to the next result would return the same iterator
	 * at its current state.