前段時(shí)間項(xiàng)目比較緊張，今天終于有空繼續(xù)更新這個(gè)專題了。在這里記錄下Spring Boot中整合MyBatis的步驟，搜了一下Spring Boot整合MyBatis的文章，不少都有些過時(shí)了。目前spring boot已經(jīng)有mybatis starter支持，大大降低了接入成本。下面就來詳細(xì)介紹如何在Spring Boot中整合MyBatis，并通過druid管理數(shù)據(jù)庫(kù)連接池。

整合MyBatis和Druid

• 新建Spring Boot項(xiàng)目

• pom.xml中引入依賴

  • 這里用到spring-boot-starter基礎(chǔ)和spring-boot-starter-test用來做單元測(cè)試驗(yàn)證數(shù)據(jù)訪問
  • 引入連接mysql的必要依賴mysql-connector-java
  • 引入整合MyBatis的核心依賴mybatis-spring-boot-starter
  • 這里不引入spring-boot-starter-jdbc依賴，是由于mybatis-spring-boot-starter中已經(jīng)包含了此依賴
  • 引入alibaba的druid依賴

      <!--MyBatis 及 插件依賴 -->
      <dependency>
          <groupId>org.mybatis.spring.boot</groupId>
          <artifactId>mybatis-spring-boot-starter</artifactId>
          <version>1.3.1</version>
      </dependency>
  
      <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-test</artifactId>
          <scope>test</scope>
      </dependency>
  
      <dependency>
          <groupId>mysql</groupId>
          <artifactId>mysql-connector-java</artifactId>
          <version>5.1.21</version>
      </dependency>
  
      <!-- druid依賴-->
      <dependency>
          <groupId>com.alibaba</groupId>
          <artifactId>druid</artifactId>
          <version>1.0.11</version>
      </dependency>
  
  

• 在application.properties中配置mysql的連接配置，如下：

druid.url=jdbc\:mysql://localhost:3306/job?useUnicode=true&characterEncoding=UTF-8
druid.driver-class=com.mysql.jdbc.Driver
druid.username=root
druid.password=123456
druid.initial-size=1
druid.min-idle=1
druid.max-active=20
druid.test-on-borrow=true

• 引入DruidAutoConfiguration

@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;
    }
}

• 引入DruidProperties

@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;

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getDriverClass() {
        return driverClass;
    }

    public void setDriverClass(String driverClass) {
        this.driverClass = driverClass;
    }

    public int getMaxActive() {
        return maxActive;
    }

    public void setMaxActive(int maxActive) {
        this.maxActive = maxActive;
    }

    public int getMinIdle() {
        return minIdle;
    }

    public void setMinIdle(int minIdle) {
        this.minIdle = minIdle;
    }

    public int getInitialSize() {
        return initialSize;
    }

    public void setInitialSize(int initialSize) {
        this.initialSize = initialSize;
    }

    public boolean isTestOnBorrow() {
        return testOnBorrow;
    }

    public void setTestOnBorrow(boolean testOnBorrow) {
        this.testOnBorrow = testOnBorrow;
    }
}

使用MyBatis

在Mysql中創(chuàng)建User表，包含id(BIGINT)、name(VARCHAR)、age(INT)字段。同時(shí)，創(chuàng)建映射對(duì)象User

public class User {
    private Long id;
    private String name;
    private Integer age;
    // 省略getter和setter
}

創(chuàng)建User映射的操作UserMapper，為了后續(xù)單元測(cè)試驗(yàn)證，實(shí)現(xiàn)插入和查詢操作

@Mapper
public interface UserMapper {
    @Select("SELECT * FROM USER WHERE NAME = #{name}")
    User findByName(@Param("name") String name);
    @Insert("INSERT INTO USER(NAME, AGE) VALUES(#{name}, #{age})")
    int insert(@Param("name") String name, @Param("age") Integer age);
}

創(chuàng)建Spring Boot主類

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

創(chuàng)建單元測(cè)試
測(cè)試邏輯：插入一條name=AAA，age=20的記錄，然后根據(jù)name=AAA查詢，并判斷age是否為20
測(cè)試結(jié)束回滾數(shù)據(jù)，保證測(cè)試單元每次運(yùn)行的數(shù)據(jù)環(huán)境獨(dú)立

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = Application.class)
public class ApplicationTests {
    @Autowired
    private UserMapper userMapper;
    @Test
    @Rollback
    public void findByName() throws Exception {
        userMapper.insert("AAA", 20);
        User u = userMapper.findByName("AAA");
        Assert.assertEquals(20, u.getAge().intValue());
    }
}

后記

上面主要介紹了利用注解來實(shí)現(xiàn)mapper的情況，下一篇文章將會(huì)介紹在spring boot集成mybatis的xml形式，以及方便的分頁(yè)插件，敬請(qǐng)期待。

【參考鏈接】
http://blog.didispace.com/springbootmybatis/
http://blog.csdn.net/CSDN3436/article/details/68491069