SpringBoot整合Mybatis

一、整合

项目包结构如下图所示：

1、pom文件

<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>BootProject</groupId>
<artifactId>BootProject</artifactId>
<version>0.0.1-SNAPSHOT</version>

<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.2.RELEASE</version>
</parent>
<!-- 管理版本 -->
<properties>
<java.version>1.8</java.version>
<mybatis.version>3.2.6</mybatis.version>
<mysql.version>5.1.38</mysql.version>
<mybatis.generator.version>1.3.2</mybatis.generator.version>
</properties>
<dependencies>
<!-- spring -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<!-- mybatis -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>${mybatis.version}</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.2.2</version>
</dependency>
<!-- mybatis generator -->
<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<version>${mybatis.generator.version}</version>
<scope>compile</scope>
<optional>true</optional>
</dependency>
<!-- Mysql -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
<version>1.4.0.RELEASE</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.2</version>
<configuration>
<verbose>true</verbose>
<overwrite>true</overwrite>
</configuration>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
</project>

注：这里没有采用通用mapper。

2、generator生成实体和mapper

注：这里采用pdm生成数据库表，根据表逆向工程生成实体和mapper文件。

配置generatorConfig.xml

<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE generatorConfiguration
PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
"http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
<!-- 配置参数从properties中读取 -->
<properties resource="generatorConfig.properties" />
<context id="Mysql" targetRuntime="MyBatis3Simple">
<commentGenerator>
<property name="suppressAllComments" value="true"/>
</commentGenerator>
<!-- 数据库连接 -->
<jdbcConnection driverClass="${jdbc.driverClass}"
connectionURL="${jdbc.url}" userId="${jdbc.user}" password="${jdbc.password}">
</jdbcConnection>
<javaTypeResolver>
<property name="forceBigDecimals" value="false"/>
</javaTypeResolver>
<!-- 实体 -->
<javaModelGenerator targetPackage="com.mybatis.model" targetProject="src/main/java">
<property name="enableSubPackages" value="true"/>
<property name="trimStrings" value="true"/>
</javaModelGenerator>
<!-- mapper文件 -->
<sqlMapGenerator targetPackage="sqlmap" targetProject="src/main/resources">
<property name="enableSubPackages" value="true"/>
</sqlMapGenerator>
<!-- mapper接口 -->
<javaClientGenerator type="XMLMAPPER" targetPackage="com.mybatis.mapper" targetProject="src/main/java">
<property name="enableSubPackages" value="true"/>
</javaClientGenerator>
<!-- tableName表名，domainObjectName实体名 -->
<table  tableName="t_User" domainObjectName="User" enableCountByExample="false" enableSelectByExample="false" enableUpdateByExample="false" enableDeleteByExample="false">

</table>
</context>

</generatorConfiguration>

generatorConfig.properties

jdbc.driverClass = com.mysql.jdbc.Driver
jdbc.url = jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8
jdbc.user = root
jdbc.password = root
mapper.plugin = tk.mybatis.mapper.generator.MapperPlugin
mapper.Mapper = tk.mybatis.mapper.common.Mapper

执行maven命令：mybatis-generator:generate，刷新项目即可。

3、注入mapper接口代理

/**
* @author  saixing_yang@hiersun.com
* @date 创建时间：2016年12月21日 下午4:35:59
* @version 1.0
*/
@Configuration  //刷新配置信息 boot会自动注入datasource，但mapper的路径需要手动注入
@EnableTransactionManagement // 启注解事务管理，等同于xml配置方式的 <tx:annotation-driven />
public class MybatisConfig implements TransactionManagementConfigurer {
@Autowired
private DataSource dataSource;

@Bean(name = "sqlSessionFactory")
public SqlSessionFactory sqlSessionFactory() throws Exception {
SqlSessionFactoryBean bean =new SqlSessionFactoryBean();
bean.setDataSource(dataSource);
bean.setMapperLocations(new PathMatchingResourcePatternResolver().
getResources("classpath:com/common/dao/mapper/UserMapper.xml"));
return bean.getObject();
}
@Bean
public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) {
return new SqlSessionTemplate(sqlSessionFactory);
}

@Override
public PlatformTransactionManager annotationDrivenTransactionManager() {
return new DataSourceTransactionManager(dataSource);
}
}

MybatisMapperScannerConfig 自动扫描配置

@Configuration
public class MybatisMapperScannerConfig {
@Bean
public MapperScannerConfigurer mapperScannerConfigurer() {
MapperScannerConfigurer scanner = new MapperScannerConfigurer();
scanner.setSqlSessionFactoryBeanName("sqlSessionFactory");  //set 手动配置的sqlSessionFactory
scanner.setBasePackage("com.common.dao");
return scanner;
}
}

二、常见问题

SpringBoot扫描包问题

报错信息：Consider defining a bean of type in your configuration

方法一：

使用注解 @ComponentScan(value=”com.common”)，其中，com.common为包路径。

方法二：

将启动类Application放在上一级包中。

如下图所示：

三、总结

SpringBoot使得开发效率大大提升，我们不再需要写一堆繁琐的配置文件来说明类与类的关系。取而代之的是，我们只需要关心如何让一个Bean可以被springboot扫描到就好了。

嘿嘿，这感觉好像你之前要自己去超市购物，然后带回家。现在有人帮你买了拿回来，但你需要把你家的地址告诉他，然后你就可以省出很多时间做其他的事情了。