package Dao;

import java.util.*;
import java.io.*;

public final class Env{
	private static Env instance;
	
	public static Env getInstance()
	{
		if(instance != null)
		{
			return instance;
		}
		else
		{
			makeInstance();
			return instance;
		}
	}
	public static synchronized void makeInstance()
	{
		if(instance == null)
		{
			instance = new Env();
		}
	}
	private Env()
	{
		Properties p = new Properties();
		InputStream is = getClass().getResourceAsStream("db.properties");
		try
		{
			p.load(is);
			PropertyConfigurator.configure(p);
			
		}catch(Exception e)
		{
			System.out.println("錯誤:沒有讀取屬性文件,請確認db.properties文件是否存在");
		}
	}
}