public static String addUtf8Charset(String contentType)
    {
        if (contentType == null)
        {
            return "text/plain;charset=utf-8";
        }

        Matcher matcher = CHARSET_PATT.matcher(contentType);
        if (matcher.find())
        {
            // replace what ever content-type with utf8
            return contentType.substring(0, matcher.start(1)) + "utf-8" + contentType.substring(matcher.end(1));
        }

        return contentType + ";charset=utf-8";
    }
public static String addUtf8Charset ( String contentType ) { if ( contentType == null ) { return "text/plain;charset=utf-8" ; } Matcher matcher = CHARSET_PATT . matcher ( contentType ) ; if ( matcher . find ( ) ) { return contentType . substring ( 0 , matcher . start ( 1 ) ) + "utf-8" + contentType . substring ( matcher . end ( 1 ) ) ; } return contentType + ";charset=utf-8" ; }
Adds the utf-8 charset to a content type.

@param contentType
@return the {@code contentType} with {@literal ;charset=utf-8} appended.