Checkstyle and Generics

I'm trying to correct all Checkstyle warnings for my project, but I keep stumbling 开发者_JAVA技巧over something very annoying when I need to construct a class that takes a Generics argument. Take the following line, for example:

labels = new HashSet < String >();

Then Checkstyle complains that '">" is not followed by whitespace'. So I write the whitespace:

labels = new HashSet < String > ();

And now it complains that '"(" is preceded by whitespace'.

Is this a bug? Is there a way to bypass it without adding a @SupressWarnings annotation?

Make sure you are running at least the 5.0 version of Checkstyle as it fixed the handling of generics. See the release notes http://checkstyle.sf.net/releasenotes.html.

It probably thinks the > is a greater than operator because there is a space before it.

The common way to space generics declarations is like this:

labels = new HashSet<String>();

Unless your checkstyle rules are tweaked, the above should most likely pass.

I have Checkstyle version 6.17 in use and I got this resolved by removing GENERIC_START and GENERIC_END from the tokens field in WhitespaceAround rule.