Spring MVC “redirect:” prefix always redirects to http — how do I make it stay on https?

The short answer is, set the InternalResourceViewResolver’s redirectHttp10Compatible property to false:

<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
  <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
  <property name="prefix" value="https://stackoverflow.com/" />
  <property name="suffix" value=".jsp" />
  <property name="redirectHttp10Compatible" value="false" />
</bean>

You could do this on a per-request basis instead, by having your handler method return View instead of String, and creating the RedirectView yourself, and calling setHttp10Compatible(false).

(It turns out the culprit is HttpServletResponse.sendRedirect, which the RedirectView uses for HTTP 1.0 compatible redirects, but not otherwise. I guess this means it’s dependent on your servlet container’s implementation (?); I observed the problem in both Tomcat and Jetty.)