public String canonicalizeUsername(String username) {
        return canonicalize(username, usernames);
    }
Canonicalizes the given username according to whether usernames are
case-sensitive under this case sensitivity setting. This function is
equivalent to manually invoking {@link #canonicalize(java.lang.String, boolean)}
with the value of {@link #caseSensitiveUsernames()}.

@param username
    The username to canonicalize.

@return
    The given username, transformed as necessary to ensure that
    verbatim string comparisons are consistent with the case sensitivity
    setting for usernames.
guacamole-ext/src/main/java/org/apache/guacamole/properties/CaseSensitivity.java