如何在整个servlet中禁用网页缓存 [英] how to disable web page cache throughout the servlets

问题描述

对于没有缓存的网页，在java控制器servlet中，我在一种方法中做了这样的事情:

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;
}

但这仅适用于特定的响应对象.我在Servlet中有许多类似的方法.而且我也有很多servlet.

But this only works for a particular response object. I have many similar methods in a servlet. And I have many servlets too.

如果我想在整个应用程序中禁用缓存，该怎么办?(我不想为每个响应对象添加以上代码).

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).

推荐答案

为什么不这样做通过过滤器?

过滤器是可以转换请求或响应的标头和内容(或两者)的对象.

A filter is an object that can transform the header and content (or both) of a request or response. 

...

过滤器可以执行的主要任务如下:

The main tasks that a filter can perform are as follows:

...

• 修改响应头和数据.您可以通过提供响应的自定义版本来做到这一点.

只需注册您的Filter(实现Filter接口的类)并在 doFilter 方法.

Just register your Filter (class implementing the Filter interface) and modify your response within the doFilter method.

编辑:例如

@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() {
    }
}

请注意， @WebFilter 批注将需要Servlet 3.0，否则您可以通过 web.xml 进行注册.此路径"/*"将适用于您的应用程序的任何路径，但范围可能会缩小.

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.

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