泛型DAO

泛型DAO标准：

在公司里面，用的基本上都是泛型DAO，实现了代码的重用性。（需要认真体会，总结）

目录结构如下：

package dao;

import java.io.Serializable;
import java.util.List;

public interface IGenericDAO<ID extends Serializable,T> {
	void insert(T entity) ;
	void delete(ID id) ;
	void deleteAll() ;
	void update(T entity) ;
    T load(ID id) ;
	List<T> list() ;
	Page<T> page(int currentPage,int pageSize,String sql);

}

package dao.impl;

import java.lang.reflect.ParameterizedType;
import java.util.List;

import dao.IGenericDAO;
import dao.Page;

public abstract class GenericDAOImpl<T> implements IGenericDAO<Integer, T> {
	
	private Class<?> clazz=null;
	
	public GenericDAOImpl() {
		ParameterizedType ptype=(ParameterizedType)(this.getClass().getGenericSuperclass());
		clazz=(Class<?>)(ptype.getActualTypeArguments()[0]);
       System.out.println(clazz);
	}

	@Override
	public void insert(T entity) {
		
	}

	@Override
	public void delete(Integer id) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void deleteAll() {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void update(T entity) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public T load(Integer id) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public List<T> list() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Page<T> page(int currentPage, int pageSize, String sql) {
		// TODO Auto-generated method stub
		return null;
	}


}

package dao;

import entity.User;


public interface IUserDAO extends IGenericDAO<Integer, User>{
	User login();

}

package dao.impl;

import dao.IUserDAO;
import entity.User;

public class UserDAOImpl extends GenericDAOImpl<User> implements IUserDAO {

	@Override
	public User login() {
		// TODO Auto-generated method stub
		return null;
	}

}

package dao;

public class Page<T> {
   
}

package entity;

import java.io.Serializable;

public class User implements Serializable {

}

package test;

import dao.IUserDAO;
import dao.impl.UserDAOImpl;

public class Demo {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
        IUserDAO udao=new UserDAOImpl();
        udao.login();
        
	}

}