Best way to create SEO friendly URI string

Question

The method should allows only "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-" chars in URI strings.

What is the best way to make

Answer 1

This is what the general consensus is:

1. Lowercase the string.

   string = string.toLowerCase();
   

2. Normalize all characters and get rid of all diacritical marks (so that e.g. é, ö, à becomes e, o, a).

   string = Normalizer.normalize(string, Form.NFD).replaceAll("\\p{InCombiningDiacriticalMarks}+", "");
   

3. Replace all remaining non-alphanumeric characters by - and collapse when necessary.

   string = string.replaceAll("[^\\p{Alnum}]+", "-");
   

So, summarized:

public static String toPrettyURL(String string) {
    return Normalizer.normalize(string.toLowerCase(), Form.NFD)
        .replaceAll("\\p{InCombiningDiacriticalMarks}+", "")
        .replaceAll("[^\\p{Alnum}]+", "-");
}