java 前后端分离跨域问题

java跨域实现类

 package com.sq.filter;

 import org.springframework.stereotype.Component;

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


 @Component
 public class AccessFilter extends HttpServlet implements Filter {

     private static final long serialVersionUID = 1L;


     @Override
     public void init(FilterConfig filterConfig) throws ServletException {

     }

     @Override
     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {

         HttpServletResponse httpResponse = (HttpServletResponse) response;
         httpResponse.setHeader("Access-Control-Allow-Origin", "*");
         httpResponse.setHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE");
         httpResponse.setHeader("Access-Control-Max-Age", "1800");
         httpResponse.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
         httpResponse.setHeader("Access-Control-Allow-Credentials", "true");
         chain.doFilter(request, httpResponse);
     }
 }

   web.xml 配置：

      <filter>
          <filter-name>crosfilter-name>
          <filter-class>com.sq.filter.AccessFilterfilter-class>
      filter>
      <filter-mapping>
          <filter-name>crosfilter-name>
          <url-pattern>/*url-pattern>
      filter-mapping>

 java跨域实现类：