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.Driverjdbc.url = jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8jdbc.user = rootjdbc.password = rootmapper.plugin = tk.mybatis.mapper.generator.MapperPluginmapper.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  [e-mail] * @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

@Configurationpublic 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。