userdaofactory.java

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/* 
 * Created on 2007-1-14
 * Last modified on 2007-1-14
 * Powered by YeQiangWei.com
 */
package com.yeqiangwei.club.dao.factory;

import com.yeqiangwei.club.dao.UserDAO;

import org.apache.log4j.Logger;

public class UserDAOFactory {
	
	private static final Logger logger = Logger.getLogger(UserDAOFactory.class.getName());
	
	private final static String className="com.yeqiangwei.club.dao.DAOImpl";
	
	private static UserDAO dao = null;
	
	public static UserDAO getInstance(){
		if(dao==null){
			try {
				dao = (UserDAO)Class.forName(className).newInstance();
			} catch (ClassNotFoundException e) {
				logger.error(e.toString());
			} catch (InstantiationException e) {
				logger.error(e.toString());
			} catch (IllegalAccessException e) {
				logger.error(e.toString());
			}
		}
		return dao;
	}
}