How to define a sort?

[KouJinrun]

I want to define a sort in my crosstab(in some rows or some columns), and I find the method [public T setComparatorExpression(DRIExpression> comparatorExpression)] in net.sf.dynamicreports.report.builder.crosstab.AbstractCrosstabGroupBuilder. But I don't know how to use it, in other words how to creat a correct comparatorExpression. So can you tell me how to use it or are there any other methos easier to achieve the purpose. Thanks!

[jan-moxter]

You can sort the data outside the report and than use

public CrosstabBuilder setDataPreSorted(Boolean dataPreSorted) {
getObject().getDataset().setDataPreSorted(dataPreSorted);
return this;
}
or use
public T orderBy(final CrosstabMeasureBuilder> measure) {
return orderBy(Expressions.orderBy(measure));
}

and the 
  final CrosstabMeasureBuilder<BigDecimal> openAmountMeasure = DynamicReports.ctab.measure("amount", "amount", BigDecimal.class, Calculation.SUM);

[KouJinrun]

Thanks for your help! The first method can work. But when I try to use the second method, it reports an error as follows :



Is there something wrong with the way I'm using it?