This subsection describes the notes on using the methods of the MimeHeaders class.

• Do not specify null in the value argument of the addHeader(String name, String value) and setHeader(String name, String value) methods. If specified, the operations are not guaranteed.
• Even if a value is set up in the Content-Length header or Content-Type header using the addHeader(String name, String value) or setHeader(String name, String value) methods, the value is overwritten when the message is sent or received.