web/play-java-forms/src/main/java/play/data/format/Formatters.java
public <T> Formatters register(final Class<T> clazz, final SimpleFormatter<T> formatter) {
    conversion.addFormatterForFieldType(
        clazz,
        new org.springframework.format.Formatter<T>() {

          public T parse(String text, Locale locale) throws java.text.ParseException {
            return formatter.parse(text, locale);
          }

          public String print(T t, Locale locale) {
            return formatter.print(t, locale);
          }

          public String toString() {
            return formatter.toString();
          }
        });

    return this;
  }
public <T> Formatters register(final Class<T> clazz, final SimpleFormatter<T> formatter) {
    conversion.addFormatterForFieldType(
        clazz,
        new org.springframework.format.Formatter<T>() {

          public T parse(String text, Locale locale) throws java.text.ParseException {
            return formatter.parse(text, locale);
          }

          public String print(T t, Locale locale) {
            return formatter.print(t, locale);
          }

          public String toString() {
            return formatter.toString();
          }
        });

    return this;
  }
Registers a simple formatter.

@param clazz class handled by this formatter
@param <T> the type that this formatter will parse and print
@param formatter the formatter to register
@return the modified Formatters object.