SpringBoot项目整合mybatis的方法步骤与实例

发布时间：2020-09-22 02:43:18 作者：双斜杠少年
来源：脚本之家阅读：140

1. 导入依赖的jar包

springboot项目整合mybatis之前首先要导入依赖的jar包，配置pom.xml文件如下：

<?xml version="1.0" encoding="UTF-8"?>
<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>com.u</groupId>
  <artifactId>springboot-mybatis</artifactId>
  <version>1.0-SNAPSHOT</version>
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.3.0.RELEASE</version>
  </parent>
  <properties>
    <start-class>com.us.Application</start-class>
    <mybatis.version>3.2.7</mybatis.version>
    <mybatis-spring.version>1.2.2</mybatis-spring.version>
    <maven.compiler.target>1.8</maven.compiler.target>
    <maven.compiler.source>1.8</maven.compiler.source>
  </properties>
  <dependencies>
    <!--springboot-->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!--db-->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>6.0.5</version>
    </dependency>
    <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.5.2</version>
      <exclusions>
        <exclusion>
          <groupId>commons-logging</groupId>
          <artifactId>commons-logging</artifactId>
        </exclusion>
      </exclusions>
    </dependency>
    <!--mybatis-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
    </dependency>
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>${mybatis.version}</version>
    </dependency>
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>${mybatis-spring.version}</version>
    </dependency>
    <!--util-->
    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-lang3</artifactId>
      <version>3.4</version>
    </dependency>
  </dependencies>
</project>

2. 配置数据源

pom.xml配置完毕后需要配置数据源了。新建DBConfig类配置数据源，代码如下：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;
import com.alibaba.druid.pool.DruidDataSource;
import com.google.common.base.Preconditions;
@Configuration
public class DBConfig {
  @Autowired
  private Environment env;
  @Bean(name = "dataSource")
  public DruidDataSource dataSource() {
    final String url = Preconditions.checkNotNull(env.getProperty("ms.db.url"));
    final String username = Preconditions.checkNotNull(env.getProperty("ms.db.username"));
    final String password = env.getProperty("ms.db.password");
    final int maxActive = Integer.parseInt(env.getProperty("ms.db.maxActive", "200"));
    DruidDataSource dataSource = new DruidDataSource();
    dataSource.setUrl(url);
    dataSource.setUsername(username);
    dataSource.setPassword(password);
    dataSource.setMaxActive(maxActive);
    return dataSource;
  }
}

3. 添加数据库连接信息

在配置文件application.properties中添加数据库连接信息如下：

ms.db.url=jdbc:mysql://localhost:3306/dev?prepStmtCacheSize=517&cachePrepStmts=true&autoReconnect=true&characterEncoding=utf-8&allowMultiQueries=true
ms.db.username=root
ms.db.password=admin
ms.db.maxActive=500

4. 配置mybatis的SqlSessionFactoryBean

数据源配置完以后要配置mybatis的SqlSessionFactoryBean进行扫描mapper，新建MyBatisConfig类代码如下（classpath*:mapper/*.xml为mapper.xml文件路径）：

import javax.sql.DataSource;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class MyBatisConfig {
  @Autowired
  private DataSource dataSource;
  @Bean(name = "sqlSessionFactory")
  public SqlSessionFactoryBean sqlSessionFactory(ApplicationContext applicationContext) throws Exception {
    SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
    sessionFactory.setDataSource(dataSource);
    sessionFactory.setMapperLocations(applicationContext.getResources("classpath*:mapper/*.xml"));
    return sessionFactory;
  }
}

5. 配置MapperScannerConfigurer扫描dao层

然后配置MapperScannerConfigurer扫描dao层，新建类MyBatisScannerConfig代码如下（注意与MyBatisConfig不要写在一个类里）：

import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class MyBatisScannerConfig {
  @Bean
  public MapperScannerConfigurer MapperScannerConfigurer() {
    MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
    mapperScannerConfigurer.setBasePackage("com.example.*.dao");
    mapperScannerConfigurer.setSqlSessionFactoryBeanName("sqlSessionFactory");
    return mapperScannerConfigurer;
  }
}

6. 开启数据库事务（必须）代码如下

import javax.sql.DataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.TransactionManagementConfigurer;
@Configuration
public class TransactionConfig implements TransactionManagementConfigurer{
  @Autowired
  private DataSource dataSource;
  @Bean(name = "transactionManager")
  @Override
  public PlatformTransactionManager annotationDrivenTransactionManager() {
    return new DataSourceTransactionManager(dataSource);
  }
}

7. 实战

配置大致就是如此，然后就是新建java bean（省略，文章底部有源码地址）

新建mapper.xml文件（省略，文章底部有源码地址，关于mapper.xml 文件编写的疑问可以看我以前的springmvc＋mybatis 系列文章）

新建dao层。代码如下：

import java.util.List;
import java.util.Map;
import com.example.base.model.User;
import com.example.config.MyBatisRepository;
public interface UserDao {
  public List<User> getList(Map<String,Object> map);
}

service层要在实现类上添加@service注解，代码如下：

import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.example.base.dao.UserDao;
import com.example.base.service.UserService;
@Service
public class UserServiceImpl implements UserService {
  @Autowired
  private UserDao userDao;
  public Object getList(Map<String, Object> map) {
    return userDao.getList(map);
  }
}

controller层也要加@controller注解代码如下：

import javax.servlet.http.HttpServletRequest;
import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import com.example.base.service.UserService;
import com.example.base.util.CommonUtil;
import com.example.demo.ServiceEmail;
@Controller
@RequestMapping(value = "/users")
public class UserController {
  @Autowired
  private UserService userService;
  @Autowired
  private ServiceEmail serviceEmail;
  /***
   * api :localhost:8099/users?id=99 localhost:8099/users
   * 
   * @param request
   * @return
   */
  @RequestMapping(method = RequestMethod.GET, produces = "application/json;charset=UTF-8")
  @ResponseBody
  public ResponseEntity<?> list(HttpServletRequest request) {
    Map<String, Object> map = CommonUtil.getParameterMap(request);
    return new ResponseEntity<Object>(userService.getList(map), HttpStatus.OK);
  }
  }

然后在启动入口类中扫描定义的这些配置累（配置包名可却省只写部分包名）如下：

import java.util.Arrays;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.web.SpringBootServletInitializer;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.scheduling.annotation.EnableScheduling;
@ComponentScan(basePackages ="com.example")
@SpringBootApplication
public class Application extends SpringBootServletInitializer{
  @Override
  protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
    return application.sources(Application.class);
  }
  public static void main(String[] args) throws Exception {
    ApplicationContext ctx = SpringApplication.run(Application.class, args);
    String[] beanNames = ctx.getBeanDefinitionNames();
    Arrays.sort(beanNames);
    for (String beanName : beanNames) {
      System.out.println(beanName);
    }
  }
}

总结

以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作具有一定的参考学习价值，谢谢大家对亿速云的支持。如果你想了解更多相关内容请查看下面相关链接

SpringBoot项目整合mybatis的方法步骤与实例

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