跨域 @CrossOrigin("*") 注解不可以跨，可以使用这个Filter

                  如果使用Filter在web实现中不要加  @CrossOrigin("*")注解。   

                   使用方法： 首先在在web层创建一个 Filter 包 中实现写法 如下

      Filter可能会导错了

import org.springframework.stereotype.Component;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Component
public class filter  implements Filter {


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
 //配置全局跨域
 HttpServletRequest re= (HttpServletRequest) servletRequest;
 HttpServletResponse res= (HttpServletResponse) servletResponse;
 //允许的域
 res.setHeader("Access-Control-Allow-Origin", re.getHeader("Origin"));
 //允许浏览器携带cookie
 res.setHeader("Access-Control-Allow-Credentials","true");
 //response.setHeader("Access-Control-Allow-Headers", "token");
 res.setHeader("Access-Control-Allow-Methods", "*");
 res.setHeader("Access-Control-Allow-Headers", "Content-Type,Access-Token");
 res.setHeader("Access-Control-Expose-Headers", "*");
 String method = re.getMethod();
 if("OPTIONS".equals(method)){

 }else{
 filterChain.doFilter(re,res);
 }
 }
}