Reference

User Common Formatter provides a factory (UserFormatterFactory) to get a user formatter:

public class UserFormatterFactory
{
    public static UserFormatter create() { /*...*/ }
    public static UserFormatter create(Pattern charactersToClean) { /*...*/ }
    public static UserFormatter create(Map<String, String> variables, Pattern charactersToClean) { /*...*/ }
}

The returned UserFormatter object allows cleaning and formating user and group names and follows this interface:  

public interface UserFormatter
{
    /**
     * @param name the user or group name to clean
     * @return the user or group name where all forbidden characters are replaced with cleanReplacement
     */
    String clean(String name);

    /**
     * Replace placeholders in a template with the provided values.
     * Placeholders are of the shape:
     * - ${key} - replaced with the value of the key
     * - ${key.lowerCase} - replaced with the value of the key, lowercased
     * - ${key._lowerCase} - replaced with the value of the key, lowercased
     * - ${key.upperCase} - replaced with the value of the key, uppercased
     * - ${key._upperCase} - replaced with the value of the key, uppercased
     * - ${key._clean}  - replaced with the value of the key, cleaned
     * - ${key.clean.lowerCase} - replaced with the value of the key, cleaned and then lowercased
     * - ${key._clean._lowerCase - replaced with the value of the key, cleaned and then lowercased
     * - ${key.clean.upperCase} - replaced with the value of the key, cleaned and then uppercased
     * - ${key._clean._upperCase} - replaced with the value of the key, cleaned and then uppercased
     * where "cleaned" means that spaces and the following characters are replaced with cleanReplacement: .:,@,^/
     * @param template the string containing placeholders to replace
     * @return the template string in which placeholders are replaced with values from the variables map
     */
    String format(String template);

    /**
     * @return the pattern to match characters to replace
     */
    Pattern charactersToClean();

    /**
     * @param charactersToClean the pattern to match characters to replace
     * @return a copy of this, with the given charactersToClean
     */
    UserFormatter charactersToClean(Pattern charactersToClean);

    /**
     * @return the available values with which to replace the placeholders
     */
    Map<String, String> variables();

    /**
     * @param variables the available values with which to replace the placeholders
     * @return a copy of this, with the given variables
     */
    UserFormatter variables(Map<String, String> variables);

    /**
     * @return what forbidden characters are replaced with
     */
    String cleanReplacement();

    /**
     * @param cleanReplacement what forbidden characters are replaced with
     * @return a copy of this, with the given cleanReplacement
     */
    UserFormatter cleanReplacement(String cleanReplacement);
}