Spring Boot 集成MyBatis

本文将介绍Spring Boot集成MyBatis、分页插件PageHelper、通用Mapper以及Druid。

新建一个maven项目，最终项目结构如下：

springbootmybatisdemo.png

POM中增加如下依赖：

<!--JSON-->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.datatype</groupId>
            <artifactId>jackson-datatype-joda</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.module</groupId>
            <artifactId>jackson-module-parameter-names</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.11</version>
        </dependency>
        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.2.0</version>
        </dependency>
        <!--mapper-->
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>1.1.0</version>
        </dependency>
        <!--pagehelper-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.1.0</version>
        </dependency>

增加Druid相关的配置

1、在application.yml中增加配置

druid:
    url: jdbc:mysql://127.0.0.1:3306/antsoft?characterEncoding=UTF-8@&autoReconnect=true&zeroDateTimeBehavior=convertToNull&useUnicode=true&characterEncoding=utf-8
    username: root
    password: root
    initial-size: 5
    min-idle: 1
    max-active: 100
    test-on-borrow: true

2、增加Druid的属性装载类

@ConfigurationProperties(prefix = "druid")
public class DruidProperties {
    private String url;
    private String username;
    private String password;
    private String driverClass;

    private int     maxActive;
    private int     minIdle;
    private int     initialSize;
    private boolean testOnBorrow;
    
    ....
}

3、增加Druid的配置类

@Configuration
@EnableConfigurationProperties(DruidProperties.class)
@ConditionalOnClass(DruidDataSource.class)
@ConditionalOnProperty(prefix = "druid", name = "url")
@AutoConfigureBefore(DataSourceAutoConfiguration.class)
public class DruidAutoConfiguration {

    @Autowired
    private DruidProperties properties;

    @Bean
    public DataSource dataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setUrl(properties.getUrl());
        dataSource.setUsername(properties.getUsername());
        dataSource.setPassword(properties.getPassword());
        if (properties.getInitialSize() > 0) {
            dataSource.setInitialSize(properties.getInitialSize());
        }
        if (properties.getMinIdle() > 0) {
            dataSource.setMinIdle(properties.getMinIdle());
        }
        if (properties.getMaxActive() > 0) {
            dataSource.setMaxActive(properties.getMaxActive());
        }
        dataSource.setTestOnBorrow(properties.isTestOnBorrow());
        try {
            dataSource.init();
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
        return dataSource;
    }
}

以上就完成了Druid的相关配置

Mybatis的集成

1、application.yml增加mybatis配置

mybatis:
    type-aliases-package: com.antsoft.model #实体类的包
    mapper-locations: classpath:mapper/*.xml #Mapper的xml文件

2、在Applicaton类中增加mapper的scan

@MapperScan(basePackages = "com.antsoft.mapper") //mapper的包
public class Application {
}

集成分页插件PageHelper

仅需在application.yml增加相关配置

pagehelper:
    helperDialect: mysql
    reasonable: true
    supportMethodsArguments: true
    params: count=countSql

集成通用Mapper

仅需在application.yml增加相关配置

mapper:
    mappers:
        - com.antsoft.database.BaseMapper
    not-empty: false
    identity: MYSQL

以上完成MyBatis的集成。如果需要事务，只需在service相关方法上增加@Transactional（项目中有相关的测试）

一个简单的获取分页用户列表的例子

相关的实体

@Table(name="t_user")
public class User extends BaseEntity {
    /** * 账号*/
    private String account;

    /*** 密码*/
    private String password;
  
    ...
}

BaseEntity中包含通用字段id,page,rows等（可详见代码）

Mapper

public interface UserMapper extends BaseMapper<User> {
}

由于继承了通用Mapper。这里已经包含了通用的增删改查的方法

Service

@Service
public class UserService {
    @Autowired
    private UserMapper userMapper;

    public List<User> getAll(User user){
        if (user.getPage() != null && user.getRows() != null) {
            PageHelper.startPage(user.getPage(), user.getRows());
        }
        return userMapper.selectAll();
    }

}

Controller

@RestController
@RequestMapping("/users")
public class UserController {
    @Autowired
    private UserService userService;

    @RequestMapping(value = "/all")
    public PageInfo<User> getALL(User user){
        List<User> userList = userService.getAll(user);
        return new PageInfo<>(userList);
    }
}

完成上述步骤后。通过mvn spring-boot:run启动应用。即可在http://localhost:9090/users/all访问到用户列表

本文使用代码

以下是相关文档链接
MyBatis-Spring-Boot-Starter
通用Mapper文档
PageHelper