SpringMVC:响应数据和结果视图

"1.0" encoding="UTF-8"?>

"http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  4.0.0cn.itcast
  ssm
  1.0-SNAPSHOTwarssm Maven Webapphttp://www.example.comUTF-81.81.85.0.2.RELEASE1.6.61.2.125.1.63.4.5org.aspectj
      aspectjweaver
      1.6.8org.springframework
      spring-aop
      ${spring.version}org.springframework
      spring-context
      ${spring.version}org.springframework
      spring-web
      ${spring.version}org.springframework
      spring-webmvc
      ${spring.version}org.springframework
      spring-test
      ${spring.version}org.springframework
      spring-tx
      ${spring.version}org.springframework
      spring-jdbc
      ${spring.version}junit
      junit
      4.12compilemysql
      mysql-connector-java
      ${mysql.version}javax.servlet
      servlet-api
      2.5providedjavax.servlet.jsp
      jsp-api
      2.0providedjstl
      jstl
      1.2log4j
      log4j
      ${log4j.version}org.slf4j
      slf4j-api
      ${slf4j.version}org.slf4j
      slf4j-log4j12
      ${slf4j.version}org.mybatis
      mybatis
      ${mybatis.version}org.mybatis
      mybatis-spring
      1.3.0com.fasterxml.jackson.core
      jackson-databind
      2.9.0com.fasterxml.jackson.core
      jackson-core
      2.9.0com.fasterxml.jackson.core
      jackson-annotations
      2.9.0c3p0
      c3p0
      0.9.1.2jarcompilessm
          maven-clean-plugin
          3.0.0
          maven-resources-plugin
          3.0.2
          maven-compiler-plugin
          3.7.0
          maven-surefire-plugin
          2.20.1
          maven-war-plugin
          3.2.0
          maven-install-plugin
          2.5.2
          maven-deploy-plugin
          2.8.2

"text/html;charset=UTF-8" language="java" %>

   String path=request.getContextPath();
%>"/user/testReturnString">testReturnString

"/user/testReturnVoid">testReturnVoid

"/user/testModelAndView">testModelAndView

"/user/testForwardOrRedirect">testForwardOrRedirect

"button" value="发送ajax的请求" id="btn">

package cn.itcast.controller;
import cn.itcast.domain.User;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.ModelAndView;

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

@Controller("jsonController")
@RequestMapping("/user")
public class UserController {
    @RequestMapping("/testReturnString")
    public String testReturnString(){
        System.out.println("testReturnString方法执行了............");
        return  "success";
    }
    @RequestMapping("testReturnVoid")
    public void testReturnVoid(
            HttpServletRequest request,
                               HttpServletResponse response) throws Exception{
        System.out.println("testVoid方法执行了...");
        // 编写请求转发的程序
        /* request.getRequestDispatcher("/WEB-INF/pages/success.jsp")
           .forward(request,response);*/
        // 重定向:这种方式相当于重新定向到webapp下的根目录下去寻找.
         //response.sendRedirect(request.getContextPath()+"/index.jsp");
        // 设置中文乱码
        response.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charset=UTF-8");

        // 直接会进行响应
        response.getWriter().print("你好");
        return;
    }
    /**
     * 使用关键字的方式进行转发或者重定向
     * @return
     */
    @RequestMapping("/testForwardOrRedirect")
    public String testForwardOrRedirect(){
        System.out.println("testForwardOrRedirect方法执行了...");
        // 请求的转发
        // return "forward:/WEB-INF/pages/success.jsp";
        // 重定向
        return "redirect:/index.jsp";
    }
    /*
    * 返回ModeAndView
    * @return
    * */
    @RequestMapping("/testModelAndView")
    public ModelAndView testModelAndView(){
        System.out.println("testModelAndView方法执行了...");
        // 创建ModelAndView对象
        ModelAndView mv = new ModelAndView();
        // 模拟从数据库中查询出User对象
        User user = new User();
        user.setUsername("小凤");
        user.setPassword("456");
        user.setAge(30);
        // 把user对象存储到mv对象中，也会把user对象存入到request对象
        mv.addObject("user",user);
        // 跳转到哪个页面
        mv.setViewName("success");
        return  mv;
    }

    /**
     * 模拟异步请求响应
     */
    @RequestMapping("/testAjax")
    public @ResponseBody User testAjax(@RequestBody User user){
        System.out.println("testAjax方法执行了...");
        // 客户端发送ajax的请求，传的是json字符串，后端把json字符串封装到user对象中
        System.out.println(user);
        // 做响应，模拟查询数据库
        user.setUsername("haha");
        user.setAge(40);
        // 做响应
        return user;
    }

}