集成mybatis

说明

使用 mybatis 作为持久层框架，sql 语句暴露在外部，适合做大数据量的优化

实现

1、引入 jar 包

        <!-- https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.1</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

2、在 application.yml 中添加配置

spring:
#  数据库连接配置
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/build
    username: root
    password: root

#配置mybatis
mybatis:
  mapper-locations: classpath:mapper/*.xml

3、创建文件夹，结构如下

image.png

4、添加实体类和配置文件

添加model类、mapper类、mapper配置文件：使用mybatis-generator插件自动生成

5、在启动类添加注解

@SpringBootApplication
@MapperScan(basePackages = "com.liucz.message.mapper")
public class MessageApplication {

    public static void main(String[] args) {
        SpringApplication.run(MessageApplication.class, args);
    }
}

6、添加service

import com.liucz.message.mapper.MessageBodyMapper;
import com.liucz.message.model.message.MessageBody;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class MessageService {

    @Autowired
    MessageBodyMapper messageBodyMapper;

    /**
     * 插入一条消息体
     * @param messageBody
     */
    public void insert(MessageBody messageBody) throws Exception {
        //标题验证
        if(messageBody.getTitle()==null || messageBody.getTitle().isEmpty()){
            throw new Exception("标题不能为空");
        }
        //内容验证
        if(messageBody.getContent()==null || messageBody.getContent().isEmpty()){
            throw new Exception("内容不能为空");
        }
        messageBodyMapper.insertSelective(messageBody);
    }
}

7、添加测试类

import com.liucz.message.model.message.MessageBody;
import com.liucz.message.servicce.MessageService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
public class MessageServiceTest {

    @Autowired
    MessageService messageService;

    /**
     * 插入一条消息体
     * @param
     */
    @Test
    public void insert() throws Exception {

        MessageBody messageBody = new MessageBody();
        messageBody.setTitle("消息标题");
        messageBody.setContent("消息内容");

        messageService.insert(messageBody);

    }

}