url rewriting - How to normalize a URL in Java?

Question

URL normalization (or URL canonicalization) is the process by which URLs are modified and standardized in a consistent manner. The goal of the normalization process is to transform a URL into a normalized or canonical URL so it is possible to determine if two syntactically different URLs are equivalent.

Strategies include adding trailing slashes, https => http, etc. The Wikipedia page lists many.

Got a favorite method of doing this in Java? Perhaps a library (Nutch?), but I'm open. Smaller and fewer dependencies is better.

I'll handcode something for now and keep an eye on this question.

EDIT: I want to aggressively normalize to count URLs as the same if they refer to the same content. For example, I ignore the parameters utm_source, utm_medium, utm_campaign. For example, I ignore subdomain if the title is the same.

Answer 1

Have you taken a look at the URI class?

http://docs.oracle.com/javase/7/docs/api/java/net/URI.html#normalize()