Spring boot集成 MyBatis 通用Mapper

配置

POM文件

<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.6.RELEASE</version> <relativePath /> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>tk.mybatis</groupId> <artifactId>mapper-spring-boot-starter</artifactId> <version>RELEASE</version> </dependency> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper-spring-boot-starter</artifactId> <version>RELEASE</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <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-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies>

 

同一環境1.5.7.RELEASE版本的Spring-boot會拋Caused by: java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver異常，1.5.6.RELEASE以及1.5.5.RELEASE版本親測沒問題

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application.properties配置文件

#數據庫
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test
spring.datasource.username=root
spring.datasource.password=741852
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

#mybatis&&通用Mapper
mybatis.type-aliases-package=com.karle.bean
mybatis.mapper-locations=classpath:mapper/*.xml
mapper.mappers=com.karle.tk.TkMapper
mapper.identity=MYSQL

#分頁插件
pagehelper.helperDialect=mysql
pagehelper.reasonable=true
pagehelper.supportMethodsArguments=true
pagehelper.params=count=countSql

#log
logging.file=logger.log
logging.level.*=debug

 

映射實體（省略字段get、set）

import java.util.Date; import javax.persistence.Column; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.Table; @Table(name = "user") public class User { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Integer id; /** * 名稱 */ @Column(name = "name") private String name; /** * 年齡 */ @Column(name = "age") private Integer age; /** * 身份編號 */ @Column(name = "card_no") private Integer cardNo; /** * 生日 */ @Column(name = "birthday") private Date birthday; }

 

本地通用Mapper接口（繼承通用Mapper接口）

import tk.mybatis.mapper.common.Mapper; import tk.mybatis.mapper.common.MySqlMapper; public interface TkMapper<T> extends Mapper<T>, MySqlMapper<T> { }

 

Mapper接口：基本的增、刪、改、查方法 
MySqlMapper：針對MySQL的額外補充接口，支持批量插入

業務接口（繼承“本地通用Mapper接口”）

import org.apache.ibatis.annotations.Param; import com.karle.bean.User; import com.karle.tk.TkMapper; public interface UserMapper extends TkMapper<User> { public User selectByCardNo(@Param("cardNo") int cardNo); }

 

Spring-boot啟動類，@MapperScan僅掃描業務接口包，不能掃描本地通用Mapper接口包，否則報java.lang.ClassCastException: sun.reflect.generics.reflectiveObjects.TypeVariableImpl cannot be cast to java.lang.Class異常

import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication @MapperScan(basePackages = { "com.karle.mapper" }) public class SpringBootMyBatisApplication { public static void main(String[] args) { SpringApplication.run(SpringBootMyBatisApplication.class, args); } }

 

通過使用@MapperScan可以指定要掃描的Mapper類的包的路徑，比如：

@SpringBootApplication
@MapperScan("com.kfit.*.mapper")
public class App {
    public static void main(String[] args) {
       SpringApplication.run(App.class, args);
    }
}

 

或者：

@SpringBootApplication
@MapperScan("com.kfit.mapper")
public class App {
    public static void main(String[] args) {
       SpringApplication.run(App.class, args);
    }
}

 

       可以根據包的結構指定不同的表達式。

 

使用@MapperScan注解多個包

可以使用如下的方式指定多個包：

@SpringBootApplication
@MapperScan({"com.kfit.demo","com.kfit.user"})
public class App {
    public static void main(String[] args) {
       SpringApplication.run(App.class, args);
    }
}

 

       如果mapper類沒有在Spring Boot主程序可以掃描的包或者子包下面，可以使用如下方式進行配置：

@SpringBootApplication
@MapperScan({"com.kfit.*.mapper","org.kfit.*.mapper"})
public class App {
    public static void main(String[] args) {
       SpringApplication.run(App.class, args);
    }
}

單元測試

import java.util.ArrayList; import java.util.Date; import java.util.List; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import org.springframework.test.context.junit4.SpringRunner; import com.github.pagehelper.PageHelper; import com.karle.bean.User; import com.karle.mapper.UserMapper; @RunWith(SpringRunner.class) @SpringBootTest public class SpringBootMyBatisApplicationTests { @Autowired private UserMapper mapper; // 插入一條新記錄 @Test public void insertOne() { User newUser = new User(); int cardNo = (int) (Math.random() * 10000000); newUser.setAge(24); newUser.setBirthday(new Date()); newUser.setName(cardNo + "用戶"); newUser.setCardNo(cardNo); mapper.insertSelective(newUser); System.out.println("插入成功"); } // 批量插入記錄 @Test public void insertMore() { List<User> recordList = new ArrayList<User>(); for (int i = 0; i < 2; i++) { User newUser = new User(); int cardNo = (int) (Math.random() * 10000000); newUser.setAge(26); newUser.setBirthday(new Date()); newUser.setName(cardNo + "批量插入用戶"); newUser.setCardNo(cardNo); recordList.add(newUser); } mapper.insertList(recordList); System.out.println("批量插入成功"); } // 根據唯一編號查詢用戶(通用Mapper查詢) @Test public void selectByCardNo() { User paramBean = new User(); paramBean.setCardNo(6647403); User dbUser = mapper.selectOne(paramBean); if (dbUser != null) { System.out.println("數據庫用戶(通用Mapper查詢)：" + dbUser.getName()); return; } System.out.println("查無此用戶"); } // 根據唯一編號查詢用戶(XML查詢) @Test public void selectByCardNoByXml() { User dbUser = mapper.selectByCardNo(6105967); if (dbUser != null) { System.out.println("數據庫用戶(XML查詢)：" + dbUser.getName()); return; } System.out.println("查無此用戶"); } // 根據年齡查詢一組用戶 @Test public void selectByAge() { User paramBean = new User(); paramBean.setAge(24); List<User> dbUserList = mapper.select(paramBean); System.out.println("總共查詢數：" + dbUserList.size()); } // 分頁查詢用戶 @Test public void selectByPage() { PageHelper.offsetPage(1, 5); List<User> dbUserList = mapper.select(null); for (User item : dbUserList) { System.out.println("分頁用戶：" + item.getName()); } } // 更新用戶信息 @Test public void updateOneInfo() { User paramBean = new User(); paramBean.setId(1); paramBean.setAge(26); mapper.updateByPrimaryKeySelective(paramBean); System.out.println("更新成功"); } }

事物的使用

spring Boot 使用事務非常簡單，首先使用注解 @EnableTransactionManagement開啟事務支持后，然后在訪問數據庫的Service方法上添加注解 @Transactional 便可。

@EnableTransactionManagement放在啟動類上