code: @Nullable
    public String getEncoded (@Nullable final String sText)
    {
      if (sText == null)
        return null;
  
      final byte [] aDecodedBuffer = sText.getBytes (m_aCharset);
      final byte [] aEncodedData = getEncoded (aDecodedBuffer, 0, aDecodedBuffer.length);
  
      final StringBuilder aSB = new StringBuilder ();
      aSB.append (PREFIX)
         .append (m_aCharset.name ())
         .append (SEP)
         .append (getRFC1522Encoding ())
         .append (SEP)
         .append (StringHelper.decodeBytesToChars (aEncodedData, StandardCharsets.US_ASCII))
         .append (POSTFIX);
      return aSB.toString ();
    }
docs: Applies an RFC 1522 compliant encoding scheme to the given string of text
  with the given charset.
  <p>
  This method constructs the "encoded-word" header common to all the RFC 1522
  codecs and then invokes #getEncoded(byte []) method of a concrete class to
  perform the specific encoding.
  
  @param sText
  a string to encode
  @return RFC 1522 compliant "encoded-word"
  @throws EncodeException
  thrown if there is an error condition during the Encoding process.
  @see <a href=
  "http://download.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">
  Standard charsets</a>