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maven

• mysql-connector==>java MySql连接
• mybatis==>MyBatis包
• druid==>阿里jdbc连接池
• hive-jdbc==>hive连接

   <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.38</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.6</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.10</version>
        </dependency>
           <!-- https://mvnrepository.com/artifact/org.apache.hive/hive-jdbc -->
        <dependency>
            <groupId>org.apache.hive</groupId>
            <artifactId>hive-jdbc</artifactId>
            <version>1.1.0</version>
        </dependency>

mybatis连接hive和mysql 测试

1.创建druid连接池

//读配置文件拿出连接
public class DruidDataSourceFactory implements DataSourceFactory {
    private Properties prop;

    @Override
    public void setProperties(Properties properties) {
        this.prop = properties;
    }

    @Override
    public DataSource getDataSource() {
        //连接池的对象
        DruidDataSource druid = new DruidDataSource();
        druid.setDriverClassName(this.prop.getProperty("driver"));
        druid.setUrl(this.prop.getProperty("url"));
        druid.setUsername(this.prop.getProperty("username"));
        druid.setPassword(this.prop.getProperty("password"));
        //最大激活连接数
//        druid.setMaxActive(Integer.parseInt(this.prop.getProperty("maxactive")));
        //初始化连接个数
//        druid.setInitialSize(Integer.parseInt(this.prop.getProperty("initialsize")));
        try {
            druid.init();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return druid;
    }
}

2.数据库工具

//通过连接源创建SqlSession
public class DatabaseUtils {
    private static final String configPath = "mybatis-config.xml";

    public static SqlSession getSession(String db) {
        SqlSession session = null;
        try {
            InputStream is = Resources.getResourceAsStream(configPath);
            SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is,db.equals("mysql")?"sq":"sq1");
            session = factory.openSession();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return session;
    }

    public static void closeSession(SqlSession session) {
        session.close();
    }

}

3.创建实体类

package org.entry;

//实体类
public class Events {
    private String eventid;
    private String userid;
    private String starttime;
    private String city;
    private String states;
    private String zip;
    private String country;
    private String lat;
    private String lng;
    private String features;
}

4.创建Dao

public interface MySqlEventDAO {
    List<Events> findAll();
}

public interface HiveEventDAO {
    public List<Events> findAll();
}

5.mybatis-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>
    <typeAliases>
        <!--        别名-->
        <typeAlias type="org.example.DruidDataSourceFactory" alias="DRUID"></typeAlias>
        <typeAlias type="org.entry.Events" alias="event"></typeAlias>
    </typeAliases>
    <environments default="sq">
        <environment id="sq">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="DRUID">
                <!--名字要与druidDataSourceFactory中的配置一致-->
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://single:3306/ms_dm_intes"/>
                <property name="username" value="root"/>
                <property name="password" value="kb10"/>
            </dataSource>
        </environment>
        <!--连接hive-->
        <environment id="sq1">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="DRUID">
                <property name="driver" value="org.apache.hive.jdbc.HiveDriver"/>
                <property name="url" value="jdbc:hive2://single:10000/dwd_intes"/>
                <property name="username" value=""/>
                <property name="password" value=""/>
            </dataSource>
        </environment>
    </environments>
    <!--    映射文件-->
    <mappers>
        <mapper resource="mysql-events.xml"></mapper>
        <mapper resource="hive-events.xml"></mapper>
    </mappers>
</configuration>

6.mysql-events.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC
        "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="org.dao.MySqlEventDAO">
    <select id="findAll" resultType="event">
        select * from dm_events limit 3
    </select>
</mapper>

7.hive-events.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC
        "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="org.dao.HiveEventDAO">
    <select id="findAll" resultType="event">
        select eventid,userid,starttime,city,states,zip,country,lat,lng,features from dwd_intes.dwd_events limit 3
    </select>
</mapper>

8.测试类

public class App {
    public static void main(String[] args) {
        SqlSession session = DatabaseUtils.getSession("mysql");
        MySqlEventDAO edao = session.getMapper(MySqlEventDAO.class);
        System.out.println(edao.findAll());

        SqlSession session1 = DatabaseUtils.getSession("hive");
        HiveEventDAO edao1 = session1.getMapper(HiveEventDAO.class);
        System.out.println(edao1.findAll());

    }
}

将数据从Hive导入MySql

YM

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