Bug 207036 [Regression] The chart in an old report design can not be rendered [13]
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/render/AxesRenderer.java
{
		if ( de1 == null && de2 == null )
			return IConstants.EQUAL;
		if ( de1 == null || de2 == null )
			return IConstants.SOME_NULL;
		final Class c1 = de1.getClass( );
		final Class c2 = de2.getClass( );
		if ( c1.equals( c2 ) )
		{
			if ( de1 instanceof NumberDataElement )
			{
				return Double.compare( ( (NumberDataElement) de1 ).getValue( ),
						( (NumberDataElement) de2 ).getValue( ) );
			}
			else if ( de1 instanceof DateTimeDataElement )
			{
				final long l1 = ( (DateTimeDataElement) de1 ).getValue( );
				final long l2 = ( (DateTimeDataElement) de1 ).getValue( );
				return ( l1 < l1 ? IConstants.LESS : ( l1 == l2
						? IConstants.EQUAL : IConstants.MORE ) );
			}
			else if ( de1 instanceof TextDataElement )
			{
				throw new ChartException( ChartEnginePlugin.ID,
						ChartException.DATA_FORMAT,
						"exception.unsupported.compare.text",  
						Messages.getResourceBundle( getRunTimeContext( ).getULocale( ) ) );
			}
			else
			{