Java Checkstyle Rule To Restrict Method Empty Lines

Question

Is there a way to setup checkstyle to prevent leading, multiple or trailing empty lines in method bodies:

e.g.

private void a() {
-
int a = 1;
doStu         


        

Answer 1

To prevent multiple empty lines you can use the EmptyLineSeparator check. Its primary purpose is to ensure that there is an empty line between members in a file, but it also has a allowMultipleEmptyLines property which you can set to "false" to disallow them.

There is however currently a bug with the check that means it doesn't correctly detect multiple empty lines between methods where there is a comment (including JavaDoc) between the methods. I am working on a fix for this at the moment.

As for checking for new lines at the beginning or end of a block, I think the RegexpMultiline check would be the only option as mentioned in Pankaj's answer.