问题
To no-cache web page, in the java controller servlet, I did somthing like this in a method:
public ModelAndView home(HttpServletRequest request, HttpServletResponse response) throws Exception {
ModelAndView mav = new ModelAndView(ViewConstants.MV_MAIN_HOME);
mav.addObject("testing", "Test this string");
mav.addObject(request);
response.setHeader("Cache-Control", "no-cache, no-store");
response.setHeader("Pragma", "no-cache");
response.setDateHeader("Expires", 0);
return mav;
}
But this only works for a particular response object. I have many similar methods in a servlet. And I have many servlets too.
If I want to disable cache throughout the application, what should I do? (I do not want to add above code for every single response object).
回答1:
Why not do this via a filter?
A filter is an object that can transform the header and content (or both) of a request or response.
...
The main tasks that a filter can perform are as follows:
...
- Modify the response headers and data. You do this by providing a customized version of the response.
Just register your Filter (class implementing the Filter interface) and modify your response within the doFilter method.
EDIT: E.g.
@WebFilter("/*")
public class NoCacheFilter implements javax.servlet.Filter {
@Override
public void init(final FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(final ServletRequest servletRequest, final ServletResponse servletResponse, final FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest)servletRequest;
HttpServletResponse response = (HttpServletResponse) servletResponse;
response.setHeader("Cache-Control", "no-cache, no-store");
response.setHeader("Pragma", "no-cache");
response.setDateHeader("Expires", 0);
filterChain.doFilter(request, response);
}
@Override
public void destroy() {
}
}
Note that the @WebFilter
annotation will require Servlet 3.0, otherwise you can register it via your web.xml
. This path of "/*", would apply to any path of your application, but could be narrowed in scope.
来源:https://stackoverflow.com/questions/23943258/how-to-disable-web-page-cache-throughout-the-servlets