code: public static <T extends CharSequence> T notEmpty(T chars) {
      if (chars == null) { throw new NullPointerException(NotEmptyCharSeqMsg); }
      if (chars.length() == 0) { throw new IllegalArgumentException(NotEmptyCharSeqMsg); }
      return chars;
    }
docs: <p>
  Validate that the specified argument array is neither {@code null} nor a length of zero (no
  elements); otherwise throwing an exception.
  
  <pre>
  Assert.notEmpty(myArray);
  </pre>
  <p>
  The message in the exception is &quot;The validated array is empty&quot;.
  
  @param <T> the array type
  @return the validated array (never {@code null} method for chaining)
  @throws NullPointerException if the array is {@code null}
  @throws IllegalArgumentException if the array is empty