Spring完美解决跨域问题

一、 Spring MVC 从4.2版本开始增加了对CORS的支持在Spring MVC 中增加CORS支持非常简单,可以配置全局的规则

二、当上述配置无效的时候，可以自定义拦截器，用代码实现跨域

如：

import org.springframework.http.HttpHeaders;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class CrossInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object o) throws Exception {
        if (request.getHeader(HttpHeaders.ORIGIN) != null) {
            String origin = request.getHeader("Origin");
            response.addHeader("Access-Control-Allow-Origin", origin);
            response.addHeader("Access-Control-Allow-Credentials", "true");
            response.addHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE, PUT,PATCH, HEAD");
            response.addHeader("Access-Control-Allow-Headers", "Content-Type");
            response.addHeader("Access-Control-Max-Age", "3600");
        }
        return true;
    }
}

三、SpringMVC4.1及更老的版本的跨域问题解决

可以自定义拦截器或者过滤器，如：

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class cInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse response, Object o) throws Exception {
        System.out.println("添加跨域支持");
        //添加跨域CORS
        response.addHeader("Access-Control-Max-Age", "1800");//30 min
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Headers", "X-Requested-With,content-type,Content-Type,token");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS, PATCH");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle");
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println("afterCompletion");
    }
}

四、如果是带有cookie的跨域问题

带有cookie时，配置Access-Control-Allow-Origin项不能为*，必须是具体的值！

如：

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class cInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse response, Object o) throws Exception {
        System.out.println("添加跨域支持");
        //添加跨域CORS
        response.addHeader("Access-Control-Max-Age", "1800");//30 min
        response.setHeader("Access-Control-Allow-Origin", "http://www.demo.com:8080");
        response.setHeader("Access-Control-Allow-Headers", "X-Requested-With,content-type,Content-Type,token");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS, PATCH");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle");
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println("afterCompletion");
    }
}

以上情况是本人遇到的四种情况，如果还有不能解决的网友，欢迎在评论区留言