spring-boot集成mybatis

2018-06-18 03:44:15来源：未知阅读 ()

前提条件：已经创建一个spring-boot项目

集成步骤：

添加依赖

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>1.3.0</version>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>

application.properties中增加如下配置

spring.datasource.driverClassName = com.mysql.jdbc.Driver
spring.datasource.url = jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8
spring.datasource.username = root
spring.datasource.password = 1234   

mybatis.mapperLocations = classpath:mapper/*Dao.xml
mybatis.configLocation = classpath:mybatis-config.xml

resources下增加mybatis-config.xml(若需要其它配置可参考mybatis官网)

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <settings>
        <!-- 可以将以下划线命名的表字段与实体类中以驼峰命名的属性进行映射 -->
        <setting name="mapUnderscoreToCamelCase" value="true" />
    </settings>
</configuration>

创建与表字段进行映射的实体类User

package com.ghaien.entity;

import lombok.Getter;
import lombok.Setter;
import java.io.Serializable;
import java.util.Date;

@Getter
@Setter
public class User implements Serializable {
    private static final long serialVersionUID = -5343460982269922412L;

    private Long id;

    private String userName;

    private String password;

    private Date createTime;

    private Date updateTime;

    private Integer enable;
}

上面代码中的Getter和Setter注解可以让编译器帮你自动添加所有属性的get和set方法。也可以通过快捷键直接生成，若要使用以上方法需要引入如下依赖

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.16.18</version>
    <scope>provided</scope>
</dependency>

还需要引入插件

<plugin>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok-maven-plugin</artifactId>
    <version>1.16.18.0</version>
</plugin>

对应配置文件中路径创建UserDao.xml，并编写相关sql

<?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.ghaien.dao.UserDao">
    <sql id="allColumn">
        id, user_name, password, create_time, update_time, enable
    </sql>
    <select id="queryAll" resultType="com.ghaien.entity.User">
        select <include refid="allColumn"/>
        from user
        where enable = 1
    </select>

    <select id="queryByUserName" resultType="com.ghaien.entity.User">
        select <include refid="allColumn"/>
        from user
        where enable = 1
        and user_name = #{userName}
    </select>
</mapper>

因为有了如上mybatis-config.xml的配置，所以如user_name会自动映射到User的userName属性中，通过在mapper下添加resultMap也能有相同效果

创建UserDao接口代码如下所示

package com.ghaien.dao;

import com.ghaien.entity.User;
import org.apache.ibatis.annotations.Param;
import java.util.List;

public interface UserDao {

    List<User> queryAll();

    User queryByUserName(@Param(value = "userName") String userName);
}

若没有在Application类上增加如下注解，则需在UserDao上增加@Mapper

@MapperScan("com.ghaien.dao")

创建测试类检查是否成功集成mybatis，代码如下所示

package com.ghaien.dao;

import com.ghaien.entity.User;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import java.util.List;

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

    private Logger log = LoggerFactory.getLogger(this.getClass());

    @Autowired
    private UserDao userDao;

    @Test
    public void testQueryAll() {
        List<User> userList = userDao.queryAll();
        log.info("userList.size() = " + userList.size());
        for (User user : userList) {
            log.info("user.userName = " + user.getUserName());
        }
    }
}