Java跨域访问sessionid不一致问题处理

Myth丶恋晨 2022-02-05 05:04 344阅读 0赞

导语：直接上处理方法，具体原理请自行查阅资料.(共用两种方法解决)

常见情景：设置进session中的值，在第二次请求时获取出来的是：null

**第一种方法：针对请求较少的需求：**

一.服务器段：

设置可以支持跨域请求：

response.setHeader("Access-Control-Allow-Origin", request.getHeader("Origin"));  
/\* response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");  
response.setHeader("Access-Control-Max-Age", "3600");  
response.setHeader("Access-Control-Allow-Headers", "x-requested-with");\*/  
response.setHeader("Access-Control-Allow-Credentials","true"); //是否支持cookie跨

@RestController
    @CrossOrigin(origins = "http://127.0.0.1:8080",maxAge = 3600)
    @RequestMapping("/login")
    //@SessionAttributes(value="validCode")
    public class LoginController {
        @Autowired
        private LoginServer loginServer;
        @RequestMapping(value = "in" ,method = RequestMethod.POST)
        public void login(HttpServletRequest request, HttpServletResponse response,HttpSession session) throws ServletException, IOException {
            request.setCharacterEncoding("utf-8");
            response.setContentType("text/html;charset=utf-8");
            response.setHeader("Access-Control-Allow-Origin", request.getHeader("Origin"));
          /*  response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
            response.setHeader("Access-Control-Max-Age", "3600");
            response.setHeader("Access-Control-Allow-Headers", "x-requested-with");*/
            response.setHeader("Access-Control-Allow-Credentials","true"); //是否支持cookie跨域
            Login user=null;
            JSONObject obj=new JSONObject();
            PrintWriter out=response.getWriter();
            String code=request.getParameter("code");
            String username=request.getParameter("username");
            String pwd=request.getParameter("pwd");
            session=request.getSession();
           String validCode=(String) session.getAttribute("validCode");

2.客户端

在ajax请求中添加可以支持携带cookie;

xhrFields:{
        withCredentials:true //允许携带cookie
    },

$.ajax({
              type:"post",
              url:"http://127.0.0.1:8081/service/login/in",
              xhrFields:{
                  withCredentials:true
              },
              data:{
                  username:$("#username").val(),
                  pwd:$("#pwd").val(),
                  code:$("#code").val()
              },
              dataType:"json",
              success:function (data) {
               if(data.pass){
                   window.location.href="index.html";
    
               }else{
                  layer.alert(data.msg)
               }
              }
          })

**第二种方法：针对请求较多的需求，利用过滤器实现：**

**一.服务器创建过滤器（过滤器中设置请求头部）：**

package com.ssm.fileter;
    
    import javax.servlet.*;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    
    public class CrossDomainFilter implements Filter {
        @Override
        public void destroy() {
            // TODO Auto-generated method stub
        }
    
        @Override
        public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
            //设置跨域请求
            HttpServletResponse response = (HttpServletResponse) res;
            //此处ip地址为需要访问服务器的ip及端口号
            response.setHeader("Access-Control-Allow-Origin", "http://127.0.0.1:8080");
            response.setHeader("Access-Control-Allow-Credentials", "true");
            response.setHeader("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS, PATCH");
            response.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type,Token,Accept, Connection, User-Agent, Cookie");
            response.setHeader("Access-Control-Max-Age", "3628800");
    
          //  System.out.println("设置跨域请求");
            chain.doFilter(req, response);
        }
    
        @Override
        public void init(FilterConfig filterConfig) throws ServletException {
            // TODO Auto-generated method stub
        }
    }

二.在web.xml中引入过滤器

<filter>
        <filter-name>crossFilter</filter-name>
        <filter-class>com.ssm.fileter.CrossDomainFilter</filter-class>
      </filter>
      <filter-mapping>
        <filter-name>crossFilter</filter-name>
        <url-pattern>/*</url-pattern>
      </filter-mapping>

三.客户端：设置请求可以携带cookie