How to redirect in a servlet filter?

Question

I'm trying to find a method to redirect my request from a filter to the login page but I don't know how to redirect from servlet. I've searched but what I find is sendRedirect() method. I can't find this method on my response object in the filter. What's the cause? How can I solve this?

Answer 1

In Filter the response is of ServletResponse rather than HttpServletResponse. Hence do the cast to HttpServletResponse.

HttpServletResponse httpResponse = (HttpServletResponse) response; httpResponse.sendRedirect("/login.jsp"); 

If using a context path:

httpResponse.sendRedirect(req.getContextPath() + "/login.jsp"); 

Also don't forget to call return; at the end.

Answer 2

I'm trying to find a method to redirect my request from filter to login page

Don't

You just invoke

chain.doFilter(request, response); 

from filter and the normal flow will go ahead.

I don't know how to redirect from servlet

You can use

response.sendRedirect(url); 

to redirect from servlet