springboot整合mybatis增删查改

时间：2021-06-17 17:15:52 阅读：0 评论：0 收藏：0 [点我收藏+]

标签：rri request zone int demo 扫描 mysqld rest osi

1.选择依赖

SpringWeb，JDBC API, MybatisFramework, MysqlDriver

2.application.yml

将 application.properties改为application.yml(使用更简洁), application.yml文件内容如下:

server:
  port: 8081
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spring:
  datasource:
    username: root
    password: root
    url: jdbc:mysql://localhost:3306/mybatis?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
driver-class-name: com.mysql.cj.jdbc.Driver
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mybatis:
  mapper-locations: classpath:mapping/*Mapper.xml
  type-aliases-package: com.example.entity.demo
  
logging:
  level:
    com:
      example:
        mapper : debug

3.pom.xml

在build中配置resources，来防止我们资源导出失败的问题-->

<build>
    <resources>
        <resource>
            <directory>src/main/resourcesdirectory>
            <includes>
                <include>**/*.properties
                **/*.xmlinclude>
            includes>
            <filtering>truefiltering>
        resource>
        <resource>
            <directory>src/main/javadirectory>
            <includes>
                <include>**/*.properties
                **/*.xmlinclude>
            includes>
            <filtering>truefiltering>
        resource>
    resources>
build>

4.创建包和类

controller包UserController类, entity包User类, mapper包UserMapper(interfac接口), service包UserService类，mapping包UserMapping.xml

技术图片

5.实体类

实体类User类里声明变量，有参构造，Set()、Get()方法, 以及toString()

6.接口UserMapper

package com.example.demo.mapper;
import com.example.demo.entity.User;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Repository;
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import java.util.List;
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/**
 * @author x
 * @Date 2021/05/24
 */
@Repository
public interface UserMapper {
//    查询全部
    List<User>getAll();
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//  按id查
    User Sel(@Param("user")User user);
//  增
    int Add(@Param("user")User user);
//  改
    int Update(@Param("user")User user);
//  删
    int Delete(@Param("user")User user);
}

7.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="com.example.demo.mapper.UserMapper">
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    <resultMap id="BaseResultMap" type="com.example.demo.entity.User">
        <result column="id" jdbcType="INTEGER" property="id"/>
        <result column="userName" jdbcType="VARCHAR" property="username"/>
        <result column="passWord" jdbcType="VARCHAR" property="password"/>
        <result column="realName" jdbcType="VARCHAR" property="address"/>
    resultMap>

    <select id="getAll" resultType="com.example.demo.entity.User">
        select * from user
    select>

    <select id="Sel" resultType="com.example.demo.entity.User">
        select * from user where 1=1
        <if test="user.id != null">
            AND id = #{user.id}
        if>
    select>

    <insert id="Add" parameterType="com.example.demo.entity.User">
        INSERT INTO user
        <trim prefix="(" suffix=")" suffixOverrides=",">
            <if test="user.username != null">
                username,
            if>
            <if test="user.password != null">
                password,
            if>
            <if test="user.address != null">
                address,
            if>
        trim>
        <trim prefix="VALUES (" suffix=")" suffixOverrides=",">
            <if test="user.username != null">
                #{user.username,jdbcType=VARCHAR},
            if>
            <if test="user.password != null">
                #{user.password,jdbcType=VARCHAR},
            if>
            <if test="user.address != null">
                #{user.address,jdbcType=VARCHAR},
            if>
        trim>
    insert>

    <update id="Update" parameterType="com.example.demo.entity.User">
        UPDATE user
        <set>
            <if test="user.username != null">
                username = #{user.username},
            if>
            <if test="user.password != null">
                password = #{user.password},
            if>
            <if test="user.address != null">
                address = #{user.address},
            if>
        set>
        WHERE
        id=#{user.id}
    update>

    <delete id="Delete"  parameterType="com.example.demo.entity.User">
        DELETE FROM user WHERE id = #{user.id}
    delete>
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mapper>

8.UserService类

 /*
        Service层介于controller和dao之间作为服务层进行一些逻辑处理，
        这里逻辑太简单所以知识单纯调用dao所以不做注释
     */

package com.example.demo.service;
import com.example.demo.entity.User;
import com.example.demo.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
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/**
 * @author x
 * @Date 2021/05/24
 */
@Service
public class UserService {
    @Autowired
    UserMapper userMapper;
//查询全部
    public List<User>getAll(){
        return userMapper.getAll();
    }
//根据id查询
    public User sel(User user){
        return userMapper.Sel(user);
    }
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    public  String Add(User user){
        int a = userMapper.Add(user);
        if (a==1){
            return "添加成功";
        }else {
            return "添加失败";
        }
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    }
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    public String Update(User user){
        int a = userMapper.Update(user);
        if (a == 1) {
            return "修改成功";
        }else {
            return "修改失败";
        }
    }
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    public String Delete(User user){
        int a = userMapper.Delete(user);
        if (a == 1) {
            return "删除成功";
        }else {
            return "删除失败";
        }
    }
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}

9.UserController类

package com.example.demo.controller;
import com.example.demo.entity.User;
import com.example.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
/**
 * @author x
 * @Date 2021/05/24
 */
@RestController
@RequestMapping("/test")
public class UserController {
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    @Autowired
    private UserService userService;
//查询全部
    @RequestMapping(value = "/select", produces = "application/json;charset=UTF-8", method = RequestMethod.GET )
    @ResponseBody
    public String getAll(User user){
        return userService.getAll().toString();
    }
//根据id查询
    @RequestMapping(value = "/selectUserByid", produces = "application/json;charset=UTF-8", method = RequestMethod.GET)
    @ResponseBody
    public String GetUser(User user){
        return userService.sel(user).toString();
    }
    
    @RequestMapping(value = "/add", produces = "application/json;charset=UTF-8", method = RequestMethod.GET)
    public String Add(User user){
        return userService.Add(user);
    }
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    @RequestMapping(value = "/update", produces = "application/json;charset=UTF-8", method = RequestMethod.GET)
    public String Update(User user){
        return userService.Update(user);
    }
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    @RequestMapping(value = "/delete", produces = "application/json;charset=UTF-8", method = RequestMethod.GET)
    public String Delete(User user){
        return userService.Delete(user);
    }
}

10.DemoApplication测试类

package com.example.demo;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
 * @author x
 * @Date 2021/05/24
 */
@MapperScan("com.example.demo.mapper") //扫描的mapper
@SpringBootApplication
public class DemoApplication {
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    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
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}

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spring boot整合Mybatis增删查改