package com.hanqi.dao;

import java.sql.Connection;
import java.sql.SQLException;
//单利模式的数据库工具类
//返回数据连接
import com.mchange.v2.c3p0.ComboPooledDataSource;

public class DBHelper {

	//1.隐藏默认的构造方法
		private DBHelper()
		{
			
		}
		//2.静态的实例
		private static DBHelper dh ;
		
		//3返回实例的静态方法
		public static DBHelper  getDBHelper()
		{
			if(dh==null)
			{
				dh = new DBHelper();
			}
			return dh;
		}
		
		
		private ComboPooledDataSource  cpds = new ComboPooledDataSource("helloc3p0");
		//反回连接的方法
		public Connection  getConnection() throws SQLException
		{
			return cpds.getConnection();
		}
}