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Apache POI

Johannes Uhlmann

Joined: May 25, 2011
Posts: 5


i got a question regarding to the class hierarchy of Cell and the possibility to implement Comparable.

There are HSSFCell implements Cell and XSSFCell implements Cell. I wanted the compareTo functionality for both, hence my idea was to design a class like abstract class MyCell implements Cell, Comparable<Cell>. So i could implement compareTo but omit the Cell functions. The problem is that MyCell is not a Cell. Available options: 1.) always cast if a Cell is needed 2.) extend HSSFCell as well as XSSFCell and implement Comparable for both. Are there more options?


edit: ;-)
Paul Clapham

Joined: Oct 14, 2005
Posts: 18121

Perhaps something like

Another option would be to forget about making a Cell comparable; you can compare a MyCell object to an XSSFCell object, because you wrote the code for MyCell, but you can't compare an XSSFCell object to a MyCell object because you didn't write the code for XSSFCell. A Comparator might be a better idea.
I agree. Here's the link:
subject: Apache POI
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