java連接配接c3po資料庫連接配接池

package com.risencn.util;

import java.beans.PropertyVetoException;

import java.sql.Connection;

import java.sql.SQLException;

import com.mchange.v2.c3p0.ComboPooledDataSource;

public class DBUtilOfC3P0 {

    private static ComboPooledDataSource dataSource;

    private static DBUtilOfC3P0 instance = null;

    public String driver = "oracle.jdbc.driver.OracleDriver";

    public String url = "jdbc:oracle:thin:@localhost:1521:orcl";

    public String username = "scott";

    public String password = "tiger";

    private DBUtilOfC3P0() {

        dataSource = new ComboPooledDataSource(); // 設定jdbc連接配接資訊

        dataSource.setUser(username);

        dataSource.setPassword(password);

        dataSource.setJdbcUrl(url);

        try {

            dataSource.setDriverClass(driver);

        } catch (PropertyVetoException e) {

            e.printStackTrace();

        }

        // 設定連接配接池

        dataSource.setInitialPoolSize(30);

        dataSource.setMaxPoolSize(100);

        dataSource.setMinPoolSize(10);

    }

    // 為了保證單例性，必須使用同步關鍵字

    public synchronized static DBUtilOfC3P0 getInstance() {

        if (instance == null)

            instance = new DBUtilOfC3P0();

        return instance;

    }

    // 連接配接必要的資訊

    public Connection getConnection() throws SQLException { // 使用工廠建立連接配接

        return dataSource.getConnection();

    }

    //測試

    public static void main(String[] args) throws SQLException {

        long begin = System.currentTimeMillis();

        // 開始時刻

        for(int i=0;i<1000;i++){//獲得1000次連接配接

            Connection conn = DBUtilOfC3P0.getInstance().getConnection();

            conn.close();

        }

        long end = System.currentTimeMillis();

         System.out.println("C3P0連接配接資料庫所需要的時 間:"+(end-begin));

        // //在我的機子上1000次C3P0連接配接耗時:656毫秒

    }

}