问题描述

我有以下(缩短的)struts2 动作:

I've got the following (shortened) struts2 action:

public class MyAction extends BaseAction implements CookiesAware {

  public String execute() {

    if (cookiesMap.containsKey("BLAH"))
      blah=Integer.parseInt(cookiesMap.get("BLAH"));

      return "success";
  }

  // For handling cookies
  Map<String, String> cookiesMap;
  @Override
  public void setCookiesMap(Map<String, String> cookiesMap) {
    this.cookiesMap = cookiesMap;
  }
}

当我执行cookiesMap.containsKey"时，我得到一个空指针异常——在我看来，setCookiesMap 没有被调用.我已经实现了 CookiesAware 接口，所以我会认为它应该被调用 - 我在这里错过了什么吗?

I get a null pointer exception when i do 'cookiesMap.containsKey' - it seems to me that setCookiesMap isn't being called. I've implemented the CookiesAware interface so i would have thought that it should be getting called - have i missed something here?

谢谢

推荐答案

看来struts只支持读取cookies，你得去servlet响应才能真正设置一个cookie.

It appears that struts only supports reading cookies, you have to go to the servlet response to actually set a cookie.

最后，我选择完全绕过 struts2 cookie 支持，直接进入 servlet 请求/响应对象进行读写:

In the end, i've opted to bypass the struts2 cookie support entirely and go directly to the servlet request/response objects for both reading and writing:

public class MyAction extends ActionSupport implements ServletResponseAware, ServletRequestAware {

  public int division;

  public String execute() {

    // Load from cookie
    for(Cookie c : servletRequest.getCookies()) {
      if (c.getName().equals("cookieDivision"))
        division=Integer.parseInt(c.getValue());
    }

    // Save to cookie
    Cookie div = new Cookie("cookieDivision", String.format("%d",division));
    div.setMaxAge(60*60*24*365); // Make the cookie last a year
    servletResponse.addCookie(div);

    return "success";
  }

  // For access to the raw servlet request / response, eg for cookies
  protected HttpServletResponse servletResponse;
  @Override
  public void setServletResponse(HttpServletResponse servletResponse) {
    this.servletResponse = servletResponse;
  }

  protected HttpServletRequest servletRequest;
  @Override
  public void setServletRequest(HttpServletRequest servletRequest) {
    this.servletRequest = servletRequest;
  }
}

并且在 struts.xml 或 web.xml 中此方法不需要配置，这是一个额外的好处.所以我对这个解决方案很满意，即使它确实在光线不好的情况下绘制 struts2.

And there's no configuration required for this method in either struts.xml or web.xml, which is a bonus. So i'm happy with this solution, even if it does paint struts2 in a poor light.

这篇关于在 Struts 2 和 Struts 中使用 cookie的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持跟版网！