2.新建项目-thymeleaf

    <dependencies>
        <!-- springboot启动器 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- thymeleaf启动器 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
    </dependencies>

    <span th:text="Yuyy"></span>
    <hr>
    <span th:text="msg"></span>

    @RequestMapping("show")
    public String showInfo(Model model){
        model.addAttribute("msg", "hello thymeleaf");
        return "index";
    }