databaseconnection.java

用java编写的人事管理系统,很好的 学习下吧

/**
 * 源文件：DatabaseConnection.java
 * 作用：创建和关闭与数据的连接
 */
package mypro;

import java.sql.*;
import java.io.*;

public class DatabaseConnection
{
	private static Connection con;
	private DatabaseConnection(){}
	/*连接数据库*/
	public static Connection getConnection()  //确保只有一个数据库连接对象
	{
		if (con == null)
		{
			try
			{
				File file = new File("dataCon.ini");
				if(!file.exists())
				{
					file.createNewFile();
				}
				FileReader fr = new FileReader(file);
				BufferedReader br = new BufferedReader(fr);
				String strDriver = br.readLine();
				String strUrl = br.readLine();
				String strUser = br.readLine();
				String strPwd = br.readLine();
				Class.forName(strDriver);
				con = DriverManager.getConnection(strUrl, strUser, strPwd);
			}
			catch (FileNotFoundException fe)
			{
				fe.printStackTrace();
			}
			catch(IOException ioe)
			{
				ioe.printStackTrace();
			}
			catch(ClassNotFoundException ce)
			{
				ce.printStackTrace();
			}
			catch(SQLException sqle)
			{
				sqle.printStackTrace();
			}
		}
		return (con);
	}
	/*关闭连接*/
	public static void close(Connection conn)
	{
		try
		{
			if (conn != null)
			{
				conn.close();
			}
		}
		catch (SQLException e)
		{
			e.printStackTrace();
		}
	}
}