[大数据]C3P0、DBCP、Ｄruid数据库连接池的使用

package C3P0ConnectionPool;

import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.junit.Test;

import java.beans.PropertyVetoException;
import java.sql.Connection;
import java.sql.SQLException;

/**
 * @className: C3P0Test
 * @description: C3P0数据库连接池测试
 * @author: CCQ
 * @date: 2021/9/28
 **/
public class C3P0Test {

    //方式一：纯Java代码
    @Test
    public void TestGetConnection1() throws PropertyVetoException, SQLException {
        //获取C3P0数据库连接池
        ComboPooledDataSource cpds = new ComboPooledDataSource();
        cpds.setDriverClass( "com.mysql.jdbc.Driver" ); //loads the jdbc driver
        cpds.setJdbcUrl( "jdbc:mysql://localhost:3306/cc" );
        cpds.setUser("root");
        cpds.setPassword("root");
        //可以设置相关参数，对连接池进行管理
        //如设置初始连接池的连接数
        cpds.setInitialPoolSize(10);
        //获取连接
        Connection connection = cpds.getConnection();
        System.out.println(connection);
//        销毁连接池，一般不会这么干
//        DataSources.destroy(cpds);
    }


    //方式二：使用配置文件
    @Test
    public void TestGetConnection2() throws SQLException {
        ComboPooledDataSource cpds = new ComboPooledDataSource("helloc3p0");
        Connection connection = cpds.getConnection();
        System.out.println(connection);
    }
}

<c3p0-config>

    <named-config name="helloc3p0">
        <!-- 提供获取连接的4个基本信息-->
        <property name="driverClass">com.mysql.jdbc.Driver</property>
        <property name="jdbcUrl">jdbc:mysql://localhost:3306/cc</property>
        <property name="user">root</property>
        <property name="password">root</property>

        <!-- 进行数据库连接池管理的基本信息-->
        <!-- 当数据库连接池中的连接不够时，c3p0一次性向数据库服务器申请的连接数-->
        <property name="acquireIncrement">5</property>
        <!-- c3p0数据库连接池中初始化时的连接数-->
        <property name="initialPoolSize">10</property>
        <!-- c3p0数据库连接池中维护的最少连接数-->
        <property name="minPoolSize">10</property>
        <!-- c3p0数据库连接池中维护的最多连接数-->
        <property name="maxPoolSize">100</property>
        <!-- c3p0数据库连接池最多维护的Statement个数-->
        <property name="maxStatements">50</property>
        <!-- 每个连接中可以最多使用的Statement个数-->
        <property name="maxStatementsPerConnection">2</property>

    </named-config>
</c3p0-config>

package DBCPConnectionPool;


import org.apache.commons.dbcp2.BasicDataSource;
import org.apache.commons.dbcp2.BasicDataSourceFactory;
import org.junit.Test;

import java.io.File;
import java.io.FileInputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

/**
 * @className: TestGetConnection
 * @description: 测试DBCP数据库连接池技术
 * @author: CCQ
 * @date: 2021/10/2
 **/
public class DBCPTest {

    //方式一：
    @Test
    public void TestGetConnection() throws SQLException {
        //创建了DBCP数据库连接池
        BasicDataSource source =new BasicDataSource();

        //设置基本信息
        source.setDriverClassName("com.mysql.jdbc.Driver");
        source.setUrl("jdbc:mysql://localhost:3306/cc");
        source.setUsername("root");
        source.setPassword("root");

        //还可以设置其他涉及数据库连接池管理的相关属性
        source.setInitialSize(10);

        Connection connection = source.getConnection();
        System.out.println(connection);
    }

    //方式二：使用配置文件（推荐）
    @Test
    public void TestGetConnection1() throws Exception {
        Properties properties = new Properties();

//        //方式一：
//        InputStream resourceAsStream = ClassLoader.getSystemClassLoader().getResourceAsStream("DBCP.peoperties");
//        properties.load(resourceAsStream);

        //方式二：
        FileInputStream fileInputStream = new FileInputStream(new File("src/DBCP.properties"));
        properties.load(fileInputStream);

        BasicDataSource dataSource = BasicDataSourceFactory.createDataSource(properties);

        Connection connection = dataSource.getConnection();
        System.out.println(connection);
    }
}

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/cc
username=root
password=root
initialSize=10

package DruidConnectionPool;

import com.alibaba.druid.pool.DruidDataSourceFactory;
import org.junit.Test;

import javax.sql.DataSource;
import java.io.InputStream;
import java.sql.Connection;
import java.util.Properties;

/**
 * @className: DruidTest
 * @description: druid数据库连接池获取连接
 * @author: CCQ
 * @date: 2021/10/2
 **/
public class DruidTest {

    @Test
    public void GetConnection() throws Exception {
        Properties properties = new Properties();
        InputStream resourceAsStream = ClassLoader.getSystemClassLoader().getResourceAsStream("druid.properties");
        properties.load(resourceAsStream);
        DataSource source = DruidDataSourceFactory.createDataSource(properties);
        Connection connection = source.getConnection();
        System.out.println(connection);
    }
}

url=jdbc:mysql:///cc
username=root
password=root
driverClass=com.mysql.jdbc.Driver
initialSize=10
maxActive=10