springboot

springboot入门（一）–快速搭建一个springboot框架
springboot入门（二）–springboot常用注解及配置
springboot入门（三）-- springboot集成mybatis及mybatis generator工具使用
springboot入门（四）springboot默认日志logback配置
springboot集成RabbitMQ
springboot定时器

创建一个简单的springboot项目(注意注解)
1.
application.yml（resources目录下的配置文件，部分需改）

server:
  port: 8080
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/smbms?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai&useSSL=false
    password: 123456
    username: root

mybatis:
  mapper-locations: classpath:mappers/*Mapper.xml
  type-aliases-package: cn.kgc.demo.pojo

User.java

package cn.kgc.demo.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Data
@AllArgsConstructor
@NoArgsConstructor

public class User {
    private Long id;
    private String userName;
    private int passWord;
}

UserMapper.java

package cn.kgc.demo.mapper;

import cn.kgc.demo.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Repository;

@Mapper
public interface UserMapper {
    //查询 对象
    User getUser(@Param("id") Long id);
    //添加
    int insert(String userName);
    //修改
    int updata(User user);
    //删除
    int delete(Long id);
}

userMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.kgc.demo.mapper.UserMapper">//注意别的项目中需要改


    <select id="getUsrName" resultType="java.lang.String">
        SELECT userName FROM smbms_user where id=#{id}
    </select>

    <select id="getUser" resultType="cn.kgc.demo.pojo.User">
        SELECT * FROM smbms_user where id=#{id}
    </select>

    <insert id="insert" >
        INSERT INTO smbms_user(userName)VALUES(#{userName})
    </insert>

    <update id="updata">
        UPDATE smbms_user SET userName=#{userName} WHERE id=#{id}
    </update>

    <delete id="delete">
         DELETE FROM smbms_user WHERE id=#{id}
    </delete>
</mapper>

UserServiceImpl .java

package cn.kgc.demo.service.Impl;


import cn.kgc.demo.mapper.UserMapper;
import cn.kgc.demo.pojo.User;
import cn.kgc.demo.service.UserService;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

@Service
public class UserServiceImpl implements UserService {
    @Resource
    private UserMapper userMapper;

    @Override
    //查询 对象
    public User getUser(Long id) {
        return userMapper.getUser(id);
    }

    @Override
    //添加
    public int insert(String userName) {
        return userMapper.insert(userName);
    }

    @Override
    //修改
    public int updata(User user) {
        return userMapper.updata(user);
    }

    @Override
    //删除
    public int delete(Long id) {
        return userMapper.delete(id);
    }
}

UserController.java

package cn.kgc.demo.controller;
import cn.kgc.demo.pojo.User;
import cn.kgc.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;

@RestController
@RequestMapping("/users")
public class Controller {
    @Autowired
    private UserService userService;
   
//    查询  对象
    @GetMapping("/{id}")
    public User getUser(@PathVariable Long id){
        System.out.println("对象：======"+userService.getUser(id));
        return userService.getUser(id);
    }
    //添加用户
    @PostMapping("/")
    public int creatUser(String userName){
        return userService.insert(userName);
    }
    //修改用户
    @PutMapping("/")
    public int updata(User user){
        return userService.updata(user);
    }
    //删除
    @DeleteMapping("/{id}")
    public int delete(@PathVariable Long id){
        return userService.delete(id);
    }
}
注：@GetMapping("/{id}")，@PostMapping("/")，@PutMapping("/")，@DeleteMapping("/{id}")
	如果使用{id}，参数需加@PathVariable注解，页面访问的时候http://localhost:8080/users/2，直接写参数，不需要写成id=2

postman