MyBatis本是apache的一个开源项目iBatis,2010年这个项目由apache software foundation迁移到了google code,并且改名为MyBatis。
MyBatis是一个基于Java的持久层框架。MyBatis提供的持久层框架包括SQL Maps和Data Access Objects(DAO),它消除了几乎所有的JDBC代码和参数的手工设置以及结果集的检索。MyBatis使用简单的XML或注解用于配置和原始映射,将接口和Java的POJOs(Plain Old Java Objects,普通的Java对象)映射成数据库中的记录。
在Spring Boot应用中使用MyBatis框架操作数据库(基于XML的映射配置)。
具体实现步骤如下。
1.创建Spring Boot Web应用
2.修改pom.xml文件
3.设置Web应用ch6_6的上下文路径及数据源配置信息
4.创建实体类
5.创建数据访问接口
6.创建Mapper映射文件
7.创建业务层
8.创建控制器类MyUserController
9.在应用程序的主类中扫描Mapper接口
10.运行
server.port=8089
server.servlet.context-path=/ch6_2
spring.datasource.url=jdbc:mysql://localhost:3306/springbootjpa?serverTimezone=UTC&autoReconnect=true
spring.datasource.username=root
spring.datasource.password=admin
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.jpa.database=MYSQL
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=update
spring.jackson.serialization.indent-output=true
mybatis.type-aliases-package=com.ch.ch6_6.entity
mybatis.mapperLocations=classpath:mappers/*.xml
logging.level.com.ch.ch6_6.repository=debug
<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mybatis</groupId>
<artifactId>SpringBootMybatis</artifactId>
<version>0.0.1-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.RELEASE</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<properties>
<!-- 声明项目配置依赖编码格式为 utf-8 -->
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<fastjson.version>1.2.24</fastjson.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<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>
<!-- 添加MySQL依赖 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
<version>8.0.13</version><!--$NO-MVN-MAN-VER$ -->
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- MyBatis-Spring,Spring Boot应用整合MyBatis框架的核心依赖配置-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.0</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
<?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.ch.ch6_6.repository.MyUserRepository">
<select id="findAll" resultType="MyUser">
select * from user
</select>
</mapper>
package com.ch.ch6_6.entity;
public class MyUser {
private Integer id;
private String username;
private String password;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
package com.ch.ch6_6.repository;
import java.util.List;
import org.apache.ibatis.annotations.Mapper;
import com.ch.ch6_6.entity.MyUser;
/**
* MyBatis的Mapper映射接口
*/
@Mapper
public interface MyUserRepository {
public List<MyUser> findAll();
}
6.创建Mapper映射文件
<?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.ch.ch6_6.repository.MyUserRepository">
<select id="findAll" resultType="MyUser">
select * from user
</select>
</mapper>
package com.ch.ch6_6.service;
import java.util.List;
import com.ch.ch6_6.entity.MyUser;
public interface MyUserService {
public List<MyUser> findAll();
}
package com.ch.ch6_6.service;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.ch.ch6_6.entity.MyUser;
import com.ch.ch6_6.repository.MyUserRepository;
@Service
public class MyUserServiceImpl implements MyUserService {
@Autowired
private MyUserRepository myUserRepository;
@Override
public List<MyUser> findAll() {
return myUserRepository.findAll();
}
}
package com.ch.ch6_6.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.ch.ch6_6.entity.MyUser;
import com.ch.ch6_6.service.MyUserService;
@RestController
public class MyUserController {
@Autowired
private MyUserService myUserService;
@RequestMapping("/findAll")
public List<MyUser> findAll() {
return myUserService.findAll();
}
}
package com.ch.ch6_6;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
//配置扫描MyBatis接口的包路径
@MapperScan(basePackages = { "com.ch.ch6_6.repository" })
public class Ch66Application {
public static void main(String[] args) {
SpringApplication.run(Ch66Application.class, args);
}
}