code: public static boolean isDisplayable(Class<?> type) {
          return Enum.class.isAssignableFrom(type)
              || type == java.net.URL.class || type == java.io.File.class
              || java.math.BigInteger.class.isAssignableFrom(type)
              || java.math.BigDecimal.class.isAssignableFrom(type)
              || java.util.Date.class.isAssignableFrom(type)
              || java.sql.Date.class.isAssignableFrom(type)
              || java.sql.Time.class.isAssignableFrom(type)
              || java.sql.Timestamp.class.isAssignableFrom(type);
      }
docs: Tests whether a non-primitive type is directly displayable.
  
  @param type the class object to test
  @return whether the type is displayable