[javaEE] 開來源資料庫串連池，javaee資料庫連接

[javaEE] 開來源資料庫串連池，javaee資料庫連接

一些開源組織提供了資料來源的獨立實現：

DBCP資料庫連接池

C3P0資料庫連接池

Apache Tomcat內建的串連池

 

DBCP串連池

apache提供的串連池實現，需要匯入common-dbcp.jar commons-pool.jar

 

import java.io.FileReader;import java.sql.Connection;import java.sql.ResultSet;import java.sql.Statement;import java.util.Properties;import javax.sql.DataSource;import org.apache.commons.dbcp.BasicDataSourceFactory;public class DBCPTest {    public static void main(String[] args) throws Exception {        //匯入設定檔        Properties prop=new Properties();        prop.load(new FileReader("dbcp.properties"));        //擷取資料來源        BasicDataSourceFactory factory=new BasicDataSourceFactory();        DataSource pool=factory.createDataSource(prop);                Connection conn=pool.getConnection();        //擷取傳輸器對象        Statement statement=conn.createStatement();        //擷取結果集對象        ResultSet resultSet=statement.executeQuery("select * from user");        //遍曆        while(resultSet.next()){            String username=resultSet.getString("username");            System.out.println(username);        }        //關閉資源        resultSet.close();        statement.close();        conn.close();            }}

在項目目錄下建立dacp.properties

driverClassName=com.mysql.jdbc.Driverurl=jdbc:mysql:///javausername=rootpassword=root

 

C3P0串連池

import java.sql.Connection;import java.sql.ResultSet;import java.sql.Statement;import com.mchange.v2.c3p0.ComboPooledDataSource;public class DBCPTest {    public static void main(String[] args) throws Exception {        //使用C3P0        ComboPooledDataSource pool=new ComboPooledDataSource();        Connection conn=pool.getConnection();        //擷取傳輸器對象        Statement statement=conn.createStatement();        //擷取結果集對象        ResultSet resultSet=statement.executeQuery("select * from user");        //遍曆        while(resultSet.next()){            String username=resultSet.getString("username");            System.out.println(username);        }        //關閉資源        resultSet.close();        statement.close();        conn.close();            }}

C3P0需要在類載入目錄下建立c3p0-config.xml

<?xml version="1.0" encoding="utf-8"?><c3p0-config>    <default-config>        <property name="driverClass">com.mysql.jdbc.Driver</property>        <property name="jdbcUrl">jdbc:mysql:///java</property>        <property name="user">root</property>        <property name="password">root</property>    </default-config></c3p0-config>