集成准备
- Mybatis
- Spring
- maven
1.创建测试表
-- 创建库
CREATE DATABASE mp;
-- 使用库
USE mp;
-- 创建表
CREATE TABLE user(
id INT(11) PRIMARY KEY AUTO_INCREMENT,
last_name VARCHAR(50),
email VARCHAR(50),
gender CHAR(1),
age INT
);
INSERT INTO tbl_employee(last_name,email,gender,age) VALUES('Tom','tom@atguigu.com',1,22);
INSERT INTO tbl_employee(last_name,email,gender,age) VALUES('Jerry','jerry@atguigu.com',0,25);
INSERT INTO tbl_employee(last_name,email,gender,age) VALUES('Black','black@atguigu.com',1,30);
INSERT INTO tbl_employee(last_name,email,gender,age) VALUES('White','white@atguigu.com',0,35);
2.创建javaBean
创建一个SpringBoot项目,并选择需要的一些依赖(也可以创建之后pom文件进行添加)
这里使用的SpringBoot的版本是2.4.1,附注pom文件
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.4.1</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.mybatis-plus-studty</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.1</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>
3.数据源配置(yml文件)
spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/mp?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull&useSSL=false&allowPublicKeyRetrieval=true
username: root
password: 123456
4.编写实体类,Mapper层,启动类添加注解
实体类
package com.mybatisplusstudty.entity.entity;
import lombok.Data;
import java.io.Serializable;
/**
* (User)实体类
*
* @author makejava
* @since 2021-01-07 15:09:16
*/
@Data
public class User implements Serializable {
private static final long serialVersionUID = -34309112287712354L;
private Integer id;
private String lastName;
private String email;
private String gender;
private Integer age;
}
Mapper层
package com.mybatisplusstudty.mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.mybatisplusstudty.entity.entity.User;
/**
* @Program: mybatisplus
* @Description
* @Author: 涛涛 * ^ *
* @Create: 2021-01-07 15:12
**/
public interface UserMapper extends BaseMapper<User> {
}
启动类添加注解(用来扫描mapper的包)
package com.mybatisplusstudty;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
@MapperScan("com.mybatisplusstudty.mapper")
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
5.测试
package com.mybatisplusstudty.mapper;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import static org.junit.jupiter.api.Assertions.*;
/**
* @Description:
* @Author: 涛涛 *^*
* @Date: 2021/1/7 15:13
*/
@SpringBootTest
class UserMapperTest {
@Autowired
private UserMapper userMapper;
@Test
void test() {
userMapper.selectList(null).forEach(System.out::println);
}
}
User(id=1, lastName=Tom, email=tom@atguigu.com, gender=1, age=22)
User(id=2, lastName=Jerry, email=jerry@atguigu.com, gender=0, age=25)
User(id=3, lastName=Black, email=black@atguigu.com, gender=1, age=30)
User(id=4, lastName=White, email=white@atguigu.com, gender=0, age=35)
运行过程中并没有打印出我们执行过程中的sql语句
配置文件添加打印SQL
mybatis-plus:
configuration:
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
JDBC Connection [HikariProxyConnection@1878045132 wrapping com.mysql.cj.jdbc.ConnectionImpl@3b55dd15] will not be managed by Spring
==> Preparing: SELECT id,last_name,email,gender,age FROM user
==> Parameters:
<== Columns: id, last_name, email, gender, age
<== Row: 1, Tom, tom@atguigu.com, 1, 22
<== Row: 2, Jerry, jerry@atguigu.com, 0, 25
<== Row: 3, Black, black@atguigu.com, 1, 30
<== Row: 4, White, white@atguigu.com, 0, 35
<== Total: 4
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@31e130bf]
User(id=1, lastName=Tom, email=tom@atguigu.com, gender=1, age=22)
User(id=2, lastName=Jerry, email=jerry@atguigu.com, gender=0, age=25)
User(id=3, lastName=Black, email=black@atguigu.com, gender=1, age=30)
User(id=4, lastName=White, email=white@atguigu.com, gender=0, age=35)