public class CancellableRequestFilter implements Filter {
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    public void destroy() {
    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        try {
            chain.doFilter(request, response);
        } catch (ServletRequestAbortException e) {
            //TODO: Maybe flush/close response here.
        }
    }

    public static void endRequest() {
        throw new ServletRequestAbortException();
    }

    public static class ServletRequestAbortException extends RuntimeException {
    }
}

<% com.your.pkg.CancellableRequestFilter.endRequest(); %>