关于JS调用Java后台API跨域问题的解决方法

public class CORSFilter implements Filter {

  public void init(FilterConfig filterConfig) throws ServletException {

  }

  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
      throws IOException, ServletException {
    HttpServletResponse res = (HttpServletResponse) response;
   HttpServletRequest request1 = (HttpServletRequest) request;
   String ip = request1.getHeader("Origin");
   res.setContentType("text/html;charset=UTF-8");
   res.setHeader("Access-Control-Allow-Origin", ip);
    res.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
    res.setHeader("Access-Control-Max-Age", "0");
    res.setHeader("Access-Control-Allow-Headers",
        "Origin, No-Cache, X-Requested-With, If-Modified-Since, Pragma, Last-Modified, Cache-Control, Expires, Content-Type, X-E4M-With,userId,token");
    res.setHeader("Access-Control-Allow-Credentials", "true");
    res.setHeader("XDomainRequestAllowed", "1");
    chain.doFilter(request, response);
  }

  public void destroy() {
    // TODO Auto-generated method stub

  }

}public class CORSFilte