code: public static <T extends CharSequence> T notEmpty(final T chars, final String message, final Object... values) {
          if (chars == null) {
              throw new NullPointerException(StringUtils.simpleFormat(message, values));
          }
          if (chars.length() == 0) {
              throw new IllegalArgumentException(StringUtils.simpleFormat(message, values));
          }
          return chars;
      }
docs: <p>Validate that the specified argument character sequence is
  neither {@code null} nor a length of zero (no characters);
  otherwise throwing an exception with the specified message.
  
  <pre>Validate.notEmpty(myString, "The string must not be empty");</pre>
  
  @param <T> the character sequence type
  @param chars  the character sequence to check, validated not null by this method
  @param message  the {@link String#format(String, Object...)} exception message if invalid, not null
  @param values  the optional values for the formatted exception message, null array not recommended
  @return the validated character sequence (never {@code null} method for chaining)
  @throws NullPointerException if the character sequence is {@code null}
  @throws IllegalArgumentException if the character sequence is empty
  @see #notEmpty(CharSequence)