mac OS 运行git报错； 前端ajax请求， 数据跨域，前端获取不到数据

1.  

mac OS 运行git报错： 由于xcode问题造成的

xcode-select--install

2. 前端ajax请求， 数据跨域，前端获取不到数据

数据跨域获取不到数据， 后端代码处理：

在web.xml添加配置filter: 注意filter位置必须放置正确

    <context-param>

        <param-name>contextConfigLocation</param-name>

        <param-value>classpath:/ApplicationContext.xml</param-value>

    </context-param>

    <filter>

        <filter-name>cors</filter-name>

        <filter-class>**.**.**.filter.CorsFilter</filter-class>

    </filter>

    <filter-mapping>

        <filter-name>cors</filter-name>

        <url-pattern>/*</url-pattern>

    </filter-mapping>

    <!-- Creates the Spring Container shared by all Servlets and Filters -->

    <listener>

        <listener-class>

        org.springframework.web.context.ContextLoaderListener

        </listener-class>

    </listener>

定义class CorsFilter:

import javax.servlet.*;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.io.IOException;

public class CorsFilter implements Filter {

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletResponse response = (HttpServletResponse) servletResponse;

        HttpServletRequest request = (HttpServletRequest) servletRequest;

        String origin = (String) servletRequest.getRemoteHost()+":"+servletRequest.getRemotePort();

        response.setHeader("Access-Control-Allow-Origin", request.getHeader("Origin"));

        response.setHeader("Access-Control-Allow-Methods", request.getHeader("Access-Control-Request-Method"));

        /*response.setHeader("Access-Control-Max-Age", "3600");*/

        response.setHeader("Access-Control-Allow-Headers", request.getHeader("Access-Control-Request-Headers"));

        response.setHeader("Access-Control-Allow-Credentials","true");

        filterChain.doFilter(request, response);

    }

    public void init(FilterConfig filterConfig) throws ServletException {

    }

    public void destroy() {

        // TODO Auto-generated method stub

    }

}