Bug 190769 [Regression]The attached report pop up exception when preview
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/data/dte/QueryResultSet.java
return context.evaluate( expr );
	}
	public Object evaluate( IBaseExpression expr ) throws BirtException
	{
		if ( expr instanceof IScriptExpression )
		{
			return context.evaluate( ( (IScriptExpression) expr ).getText( ) );
		}
		if ( expr instanceof IConditionalExpression )
		{
			return context.evaluateCondExpr( (IConditionalExpression) expr );
		}
		return null;
	}
	public DataSetID getID( )
	{
		return id;
	}
	public IBaseResultSet getParent( )
	{
		return parent;
	}
	public String getRawID( ) throws BirtException
	{
		return String.valueOf( rs.getRowId( ) );
	}
	public int getType( )
	{
		return QUERY_RESULTSET;
	}