Intersect collections?

[uwe.seher]

Hello!

I have a collection col1 resulting from a multi-select input control. I want to compare this collection with two other collections col2, col3 and get a marker if they have elements in common. So there are three possibilities (col1 has only elements of col2 or col3 and col1 has elements of both, an empty col1 is not possible), the marker should be 1,2 or 3 as variable, that is used in subreport/crosstab. So my question is, how do i intersect the lists without crunching them with retainAll()? How can i realise something like col1.intersects(col2) in Jasper Community Edition 6.3?

Thank you in advance

Uwe Seher