04Spring MVC入门

Spring MVC

• 三层架构
  • 表现层
  • 业务层
  • 数据访问层
• MVC(处理表现层)
  • Model：模型层
  • View：视图层
  • Controller：控制层

底层请求方式

在controller中添加

@RequestMapping("/http")
    public void http(HttpServletRequest request, HttpServletResponse response) throws IOException {
        //获取请求数据
        System.out.println(request.getMethod());
        System.out.println(request.getServletPath());
        Enumeration<String> enumeration = request.getHeaderNames();
        while (enumeration.hasMoreElements()) {
            String name = enumeration.nextElement();
            String value = request.getHeader(name);
            System.out.println(name + ": " + value);
        }
        System.out.println(request.getParameter("code"));

        //返回响应数据
        response.setContentType("text/html;charset=utf-8");
        PrintWriter printWriter = response.getWriter();
        printWriter.write("<h1>Header<h1>");
        printWriter.close();
    }

运行并打开http://localhost:8081/community/alpha/http

GET请求

方式一：以键值对方式引入参数

// /students?current=1&limit=20
    @RequestMapping(path = "/students", method = RequestMethod.GET)
    @ResponseBody
    public String getStudents(
            @RequestParam(name = "current", required = false, defaultValue = "1") int current,
            @RequestParam(name = "limit", required = false, defaultValue = "10") int limit ) {

        System.out.println(current);
        System.out.println(limit);

        return "students";

    }

方式二：在路径中引入参数

// /student/2019213151
    @RequestMapping(path = "/student/{id}", method = RequestMethod.GET)
    @ResponseBody
    public String getStudent(@PathVariable("id") int id) {
        System.out.println(id);

        return "a student " + id;
    }

访问http://localhost:8081/community/alpha/student/101

POST请求