package com.test.filter;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebFilter(urlPatterns = "/*", filterName = "CORSFilter")
public class CORSFilter implements Filter {
 @Override
 public void destroy() {
 }
 /**
  * 此过滤器只是处理跨域问题
  * @param servletRequest
  * @param servletResponse
  * @param chain
  * @throws ServletException
  * @throws IOException
  */
 @Override
 public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain chain) throws ServletException, IOException {
  HttpServletRequest req = (HttpServletRequest) servletRequest;
  HttpServletResponse resp = (HttpServletResponse) servletResponse;
  String origin = req.getHeader("Origin");
  if(origin == null) {
   origin = req.getHeader("Referer");
  }
  resp.setHeader("Access-Control-Allow-Origin", origin);//这里不能写*，*代表接受所有域名访问，如写*则下面一行代码无效。谨记
  resp.setHeader("Access-Control-Allow-Credentials", "true");//true代表允许携带cookie
  chain.doFilter(servletRequest,servletResponse);
 }
 @Override
 public void init(FilterConfig filterConfig) throws ServletException {
 }
}

@SpringBootApplication
@EnableTransactionManagement(order = 10)
@ServletComponentScan
public class Application {
 public static void main(String[] args) {
  SpringApplication.run(Application.class, args);
 }
}

使用vue.resource发送请求时配置如下：
main.js中
Vue.http.options.xhr = { withCredentials: true }
使用vue.axios发送请求时配置如下：
axios.defaults.withCredentials = true；
jquery请求带上 xhrFields: {withCredentials: true}, crossDomain: true；
$.ajax({
 type: "post",
 url: "",
 xhrFields: {withCredentials: true},
 crossDomain: true,
 data: {username:$("#username").val()},
 dataType: "json",
 success: function(data){ }
});