daofactory.java

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package db.dao;

public class DAOFactory {
	private static Object initlock = new Object();
	private static DAOFactory factory=null;
	public static DAOFactory getInstance(){
		if(factory==null){
			synchronized (initlock){
				if(factory==null){
					try{
						factory =new DAOFactory();
					}catch(Exception e){
						e.printStackTrace();
						return null;
					}
				}
			}
		}
		return factory;
	}
	
	public UserDAO createUserDAO(){
		return new UserDAO();
	}

}