Java SpringMVC

1.新建一个maven webapp项目

2.编写web配置文件

    
    
        springmvc
        org.springframework.web.servlet.DispatcherServlet
        
            contextConfigLocation
            classpath:springmvc-servlet.xml
        
        1
    
    
        springmvc
        /
    

3.配置Spring-Servlet配置文件

4.配置controller

package com.huang.controller;

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.Controller;

public class HelloController implements Controller {
    @Override
    public ModelAndView handleRequest(javax.servlet.http.HttpServletRequest httpServletRequest, javax.servlet.http.HttpServletResponse httpServletResponse) throws Exception {
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.addObject("msg", "HelloSpringMVC");
        modelAndView.setViewName("hello");
        return modelAndView;
    }
}

1.新建maven webapp项目

2.编写web配置文件

  
    springmvc
    org.springframework.web.servlet.DispatcherServlet
    
      contextConfigLocation
      classpath:springmvc-servlet.xml
    
    1
  
  
    springmvc
    /
  

3.编写springmvc-servlet配置文件

4.添加jsp文件

5.编写controller文件

package com.huang.controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class helloController {
    @RequestMapping("/hello")
    public String hello(Model model){
        model.addAttribute("msg","你好,世界");
        return "hello";
    }
}

package com.huang.controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class helloController {
    //转发
    @RequestMapping("/hello")
    public String hello(Model model){
        model.addAttribute("msg","你好,世界");
        return "hello";
    }
    //重定向
    @RequestMapping("/hello1")
    public String hello1(Model model){
        model.addAttribute("msg","重定向");
        return "redirect:/index.jsp";
    }
}

web配置中加入Spring自带的乱码过滤器

  
    springmvc
    org.springframework.web.servlet.DispatcherServlet
    
      contextConfigLocation
      classpath:springmvc-servlet.xml
    
    1
  
  
    springmvc
    /
  
  
  
    encoding
    org.springframework.web.filter.CharacterEncodingFilter
    
      encoding
      utf-8
    
  
  
    encoding
    /*
  

controller编写转化为json字符串

导入jia包

        
        
            com.fasterxml.jackson.core
            jackson-databind
            2.13.0
        

package com.huang.controller;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.huang.pojo.User;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

@Controller
public class UserController {
    @RequestMapping("/j1")
    //跳过视图解析器,直接返回一个字符串
    @ResponseBody
    public String text() throws JsonProcessingException {
        ObjectMapper Mapper = new ObjectMapper();
        User user = new User(1, "小明", 13);
        String s = Mapper.writevalueAsString(user);
        return s;
    }
    @RequestMapping("/j2")
    //跳过视图解析器,直接返回一个字符串
    @ResponseBody
    public String text2() throws JsonProcessingException {
        ObjectMapper Mapper = new ObjectMapper();
        List Users = new ArrayList<>();
        User user1 = new User(1, "小明", 13);
        User user2 = new User(2, "小红", 13);
        User user3 = new User(3, "小蓝", 13);
        User user4 = new User(4, "小绿", 13);
        Users.add(user1);
        Users.add(user2);
        Users.add(user3);
        Users.add(user4);
        String s = Mapper.writevalueAsString(Users);
        return s;
    }
    @RequestMapping("/j3")
    //跳过视图解析器,直接返回一个字符串
    @ResponseBody
    public String text3() throws JsonProcessingException {
        ObjectMapper Mapper = new ObjectMapper();
        Date date = new Date();
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String s = Mapper.writevalueAsString(format.format(date));
        return s;
    }
    @RequestMapping("/j4")
    //跳过视图解析器,直接返回一个字符串
    @ResponseBody
    public String text4() throws JsonProcessingException {
        ObjectMapper Mapper = new ObjectMapper();
        Mapper.configure(SerializationFeature.WRITE_DURATIONS_AS_TIMESTAMPS , false);
        Date date = new Date();
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Mapper.setDateFormat(format);
        String s = Mapper.writevalueAsString(date);
        return s;
    }
}