使用MyBatis集成阿里巴巴druid连接池(不使用spring)

时间:2023-09-16 17:07:07
    • 在工作中发现mybatis默认的连接池POOLED,运行时间长了会报莫名其妙的连接失败错误。因此采用阿里巴巴的Druid数据源(码云链接 ,中文文档链接)。 mybatis更多数据源参考博客链接 。

      1 环境

      eclipse mars2 + maven3.3.9 + mysql5.7

      2 开发过程

      项目码云地址链接

      文件目录结构如下: 使用MyBatis集成阿里巴巴druid连接池(不使用spring)

      2.0 建立数据表

      在本地mysql数据库中建立名为test的database,并建立user表:


      CREATE DATABASE test default charset=utf8; CREATE TABLE `user` (
      `name` varchar(64) DEFAULT NULL,
      `age` int(11) DEFAULT NULL
      ) ENGINE=InnoDB DEFAULT CHARSET=utf8; insert into `user`(`name`,`age`) values ('叶莜落',27),('张三丰',128);

      2.1 建立一个maven工程,POM文件如下:

      <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.yeyouluo.mybatis.druid</groupId>
      <artifactId>mybatis-druid</artifactId>
      <version>0.0.1-SNAPSHOT</version> <properties>
      <myabtis.version>3.4.1</myabtis.version>
      </properties> <dependencies>
      <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>${myabtis.version}</version>
      </dependency>
      <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.30</version>
      </dependency>
      <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.0.14</version>
      </dependency>
      </dependencies>
      </project>

      2.2 配置文件

      ①db.properties

      driver=com.mysql.jdbc.Driver
      url=jdbc:mysql://localhost:3306/test
      username=root
      password=root

      ②mybatis-config.xml

      <?xml version="1.0" encoding="UTF-8" ?>
      <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
      "http://mybatis.org/dtd/mybatis-3-config.dtd">
      <configuration>
      <!-- 引用db.properties配置文件 -->
      <properties resource="db.properties" /> <typeAliases>
      <typeAlias type="com.yeyouluo.mybatis.druid.utils.DruidDataSourceFactory"
      alias="DRUID" />
      </typeAliases> <!-- development : 开发模式 work : 工作模式 -->
      <environments default="work">
      <environment id="work">
      <transactionManager type="JDBC" />
      <!-- 配置数据库连接信息 -->
      <dataSource type="DRUID">
      <!-- value属性值引用db.properties配置文件中配置的值 -->
      <property name="driver" value="${driver}" />
      <property name="url" value="${url}" />
      <property name="username" value="${username}" />
      <property name="password" value="${password}" />
      </dataSource>
      </environment>
      </environments> <!-- mybatis的mapper文件,每个xml配置文件对应一个接口 -->
      <mappers>
      <mapper resource="mapper/userMapper.xml" />
      </mappers>
      </configuration>

      ③在resources目录下建立userMapper.xml

      <?xml version="1.0" encoding="UTF-8" ?>
      <!DOCTYPE mapper PUBLIC "-//ibatis.apache.org//DTD Mapper 3.0//EN"
      "http://ibatis.apache.org/dtd/ibatis-3-mapper.dtd">
      <mapper namespace="com.yeyouluo.mybatis.druid.dao.userDao">
      <select id="findAllUsers" resultType="com.yeyouluo.mybatis.druid.pojo.User">
      select * from user
      </select>
      </mapper>

      2.3 实体类 User

      package com.yeyouluo.mybatis.druid.pojo;
      
      public class User {
      
          private String name;
      private int age; public String getName() {
      return name;
      } public void setName(String name) {
      this.name = name;
      } public int getAge() {
      return age;
      } public void setAge(int age) {
      this.age = age;
      } @Override
      public String toString() {
      return "User [name=" + name + ", age=" + age + "]";
      } }

      2.4 工具类

      ①DruidDataSourceFactory.java

      package com.yeyouluo.mybatis.druid.utils;
      
      import java.sql.SQLException;
      import java.util.Properties;
      import javax.sql.DataSource;
      import org.apache.ibatis.datasource.DataSourceFactory;
      import com.alibaba.druid.pool.DruidDataSource; public class DruidDataSourceFactory implements DataSourceFactory {
      private Properties props; @Override
      public DataSource getDataSource() {
      DruidDataSource dds = new DruidDataSource();
      dds.setDriverClassName(this.props.getProperty("driver"));
      dds.setUrl(this.props.getProperty("url"));
      dds.setUsername(this.props.getProperty("username"));
      dds.setPassword(this.props.getProperty("password"));
      // 其他配置可以根据MyBatis主配置文件进行配置
      try {
      dds.init();
      } catch (SQLException e) {
      e.printStackTrace();
      }
      return dds;
      } @Override
      public void setProperties(Properties props) {
      this.props = props;
      }
      }

      ②MyBatisUtil.java

      package com.yeyouluo.mybatis.druid.utils;
      
      import java.io.InputStream;
      
      import org.apache.ibatis.io.Resources;
      import org.apache.ibatis.session.SqlSession;
      import org.apache.ibatis.session.SqlSessionFactory;
      import org.apache.ibatis.session.SqlSessionFactoryBuilder; public class MyBatisUtil {
      private static final String configFile = "mybatis-config.xml"; /**
      * 创建连接
      */
      public static SqlSession getSession() {
      SqlSession session = null;
      try {
      InputStream is = Resources.getResourceAsStream(configFile);
      SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
      session = factory.openSession();
      } catch (Exception e) {
      e.printStackTrace();
      }
      return session;
      } public static void closeSession(SqlSession session) {
      session.close();
      } public static void main(String[] args) {
      SqlSession session = MyBatisUtil.getSession();
      System.out.println(session);
      session.close();
      }
      }

      2.5 DAO

      ①接口IUserDao.java

      package com.yeyouluo.mybatis.druid.dao;
      
      import java.util.List;
      
      import com.yeyouluo.mybatis.druid.pojo.User;
      
      public interface IUserDao {
      public List<User> findAllUsers();
      }

      ②实现类UserDao.java

      package com.yeyouluo.mybatis.druid.dao.impl;
      
      import java.util.List;
      
      import org.apache.ibatis.session.SqlSession;
      
      import com.yeyouluo.mybatis.druid.dao.IUserDao;
      import com.yeyouluo.mybatis.druid.pojo.User;
      import com.yeyouluo.mybatis.druid.utils.MyBatisUtil; public class UserDao implements IUserDao { private static final String namespace = "com.yeyouluo.mybatis.druid.dao.userDao."; @Override
      public List<User> findAllUsers() {
      List<User> users = null;
      SqlSession session = MyBatisUtil.getSession();
      try {
      users = session.selectList(namespace + "findAllUsers", User.class);
      //注意:此处有陷阱,如果做了更新、插入或删除操作,必须使用:
      //session.commit();
      } catch (Exception e) {
      e.printStackTrace();
      }finally{
      MyBatisUtil.closeSession(session);
      }
      return users;
      } }

      2.6 测试类UserDaoTest.java

      package com.yeyouluo.mybatis.druid.dao.test;
      
      import java.util.List;
      
      import com.yeyouluo.mybatis.druid.dao.IUserDao;
      import com.yeyouluo.mybatis.druid.dao.impl.UserDao;
      import com.yeyouluo.mybatis.druid.pojo.User; public class UserDaoTest { public static void main(String[] args) {
      // TODO Auto-generated method stub
      IUserDao userDao = new UserDao();
      List<User> users= userDao.findAllUsers(); for(User user : users){
      System.out.println(user.toString());
      }
      } }

      3 结果

      使用MyBatis集成阿里巴巴druid连接池(不使用spring)

      4 参考

      Jar程序使用MyBatis集成阿里巴巴druid连接池