userdaofactory.java

来自「这适合利用java开发struts程序的初学者借鉴的代码」· Java 代码 · 共 28 行

package com.struts.usermgr.factory;

import com.struts.usermgr.factory.UserDaoFactory;
import com.struts.usermgr.dao.UserDao;
import com.struts.usermgr.dao.UserDaoMysqlImpl;

public class UserDaoFactory {

	private static UserDaoFactory instance  ;
	
	private UserDao userDao ;
	
	private UserDaoFactory(){
		userDao = new UserDaoMysqlImpl() ;
	}
	
	public static synchronized UserDaoFactory getInstance() {
		if (instance == null) {
			instance = new UserDaoFactory();
		}
		return instance;
	}
	
	public UserDao createUserDao() {
		return userDao;
	}
}