jsp 数据库连接池代码

package connect;

import java.sql.*;
import java.util.ArrayList;
public class DBConnection {
	//存放Connection对象的数组，数组被看成连接池
	static ArrayList<Connection> list=new ArrayList<Connection>();
	//从连接池中取出一个连接对象
	public synchronized static  Connection getOneCon(){
		//如果连接池中有连接对象
		if(list.size()>0){
			return list.remove(0);
		}
		//连接池没有连接对象创建连接放到连接池中
		else{
			for(int i=0;i<5;i++){
				try {
					 //Class.forName("oracle.jdbc.driver.OracleDriver");
                  //  Class.forName("com.mysql.jdbc.Driver");
					 Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
                    String dbURL = "jdbc:sqlserver://localhost:1433; DatabaseName=S_Md";
                    String userName = "140551124"; // 默认用户名
                    String userPwd = "140551124"; // 密码
                    Connection  con=DriverManager.getConnection(dbURL, userName, userPwd);
                 //   Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/adsystem","root","123456");
//Connection con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","system","system");
					list.add(con);
				} catch (Exception e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
			return list.remove(0);
		}
	}
	//关闭结果集对象
	public static void close(ResultSet rs){
		try {
			if(rs!=null)
				rs.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	//关闭预处理语句
	public static void close(PreparedStatement ps){
		try {
			if(ps!=null)
				ps.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	//把连接对象放回连接池中
	public synchronized static void close(Connection con){
			if(con!=null)
				list.add(con);
	}
}