Question

I’m writing to the browser window using servletResponse.getWriter().write(String).

But how do I clear the text which was written previously by some other similar write call?

Answer 1

The short answer is, you cannot — once the browser receives the response, there is no way to take it back. (Unless there is some way to abnormally stop a HTTP response to cause the client to reload the page, or something to that extent.)

Probably the last place a response can be “cleared” in a sense, is using the ServletResponse.reset method, which according to the Servlet Specification, will reset the buffer of the servlet’s response.

However, this method also seems to have a catch, as it will only work if the buffer has not been committed (i.e. sent to the client) by the ServletOutputStream‘s flush method.