跨域的配置类

1、在项目中新建一个config的包，添加跨域的配置类

package com.mashibing.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;

@Configuration
public class CorsConfig {
    private CorsConfiguration buildConfig() {
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        //  你需要跨域的地址  注意这里的 127.0.0.1 != localhost
        // * 表示对所有的地址都可以访问
        corsConfiguration.addAllowedOrigin("*");
        //  跨域的请求头
        corsConfiguration.addAllowedHeader("*"); // 2
        //  跨域的请求方法
        corsConfiguration.addAllowedMethod("*"); // 3
        //加上了这一句，大致意思是可以携带 cookie
        //最终的结果是可以 在跨域请求的时候获取同一个 session
        corsConfiguration.setAllowCredentials(true);
        return corsConfiguration;
    }
    @Bean
    public CorsFilter corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        //配置 可以访问的地址
        source.registerCorsConfiguration("/**", buildConfig()); // 4
        return new CorsFilter(source);
    }
}

或者可以在controller类的上面添加注解

in(origins = "*",allowCredentials="true",allowedHeaders = "*",methods = {})

LoginController.java

package com.bjmsb.controller;

import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@CrossOrigin(origins = "*",allowCredentials="true",allowedHeaders = "*",methods = {})
public class LoginController {

    @RequestMapping("/auth/2step-code")
    public boolean step_code2(){
        System.out.println("此请求是前端框架带的默认请求，可以不做任何处理，也可以在前端将其删除");
        System.out.println("step_code2");
        return true;
    }

    @RequestMapping("/auth/login")
    public String login(){
        System.out.println("login");
        return "success";
    }
}