Refactored (after)

gistfile1.java

protected String getUserIdFromPrincipal(Principal prin) {
	if (prin == null) {
		throw new IllegalArgumentException(
				"User principal must not be null.");
	}
	logger.debug("URL encoded principal: " + prin);
	String strPrincipal = null;

	try {
		strPrincipal = URLDecoder.decode(prin.getName(), UTF_8);
		logger.debug("URL decoded principal: " + strPrincipal);

		logger.info("Parsing LDAP principal name");
		LdapName ldapName = new LdapName(strPrincipal);
		strPrincipal = ldapName.getRdn(2).getValue().toString();
		logger.info("User is decoded as: " + strPrincipal);
		strPrincipal = strPrincipal.toUpperCase();

	} catch (UnsupportedEncodingException e) {
		/*
		 * Exception only thrown when URLDecode.decode is called with an
		 * invalid encoding. Since we're calling it with a literal value,
		 * this catch block cannot be reached. Nonetheless, a logging
		 * statement is included here in case this method ever changes.
		 */
		logger.error("Unsupported encoding", e);
	} catch (InvalidNameException e) {
		logger.error("LDAP name string is not valid", e);
		throw new IllegalArgumentException(
				"User principal must be an LDAP distinguished name");
	}
	// Transpose user id to upper case
	return strPrincipal;
}