dcsimg

What are the restrictions / limitations for adding custom, user-defined headers?

John Zukowski

User-defined header names can consist of only printable ASCII characters, excluding the colon. They should start with an "X-", but there is no strict requirement that they do.

For example, the following would add a custom header to a message:

message.addHeader("X-FAQs",
    "http://www.jguru.com/faq");