class User {
    private String name;
    private int age;
    public void setName(String name){
        this.name=name;
    }
    public void setAge(int age){
        this.age=age;
    }
    public String getName(){
        return this.name;
    }
    public int getAge(){
        return this.age;
    }
}
interface UserDAO {
    public boolean doCreate(User user)throws Exception;
}
class UserDAOImpl implements UserDAO {
    private String str=null;
    public UserDAOImpl(String str){
        this.str=str;
    }
    public boolean doCreate(User user)throws Exception{
        boolean flag=false;
        try{
            System.out.println("真实主题类的数据库增加操作");
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            
        }
        return flag;
    }
}
class UserDAOProxy implements UserDAO {
    private UserDAOImpl dao=null;
    private String str=null;        //此处其实应该传入一个数据库的连接到真实主题类的，不过这里只是个演示，所有以字符串的形式传了进去
    public UserDAOProxy(){
        this.str=new String();
        this.dao=new UserDAOImpl(this.str);
    }
    public boolean doCreate(User user)throws Exception{
        boolean flag=true;
        System.out.println("代理类的操作，打开数据库，同时取得真实主题类的实例去调用真实的数据层操作");
        try{
            this.dao.doCreate(user);
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            System.out.println("代理类的操作，调用完真实主题类的操作，同时关闭数据库");
        }
        return flag;
    }
}
class UserDAOFactory {
    public static UserDAO getUserDAONewInstance(){
        System.out.println("通过工厂类取得代理类的实例去调用代理类的操作。");
        return new UserDAOProxy();
    }
}
public class FactoryDemo {
    public static void main(String args[])throws Exception{
        User user=new User();
        user.setName("jhjjs");
        user.setAge(20);
        UserDAOFactory.getUserDAONewInstance().doCreate(user);
    }
}