七大设计原则之单一职责原则

一个类只负责一项职责
比如 dao 层

1、类的级别上实现单一职责


public class SingleResponsibilityPrincipleDemo {

    public static void main(String[] args) {
        UserDao userDao = new UserDao();
        userDao.getUserInfo();
        VisitDao visitDao = new VisitDao();
        visitDao.getVisitInfo();
    }
}

class UserDao{
    public void getUserInfo(){
        System.out.println("获取用户信息");
    }
}

class VisitDao{
    public void getVisitInfo(){
        System.out.println("获取访问信息");
    }
}

2、方法的级别上实现单一职责

public class SingleResponsibilityPrincipleDemo1 {

    public static void main(String[] args) {
        UserInfo userInfo = new UserInfo();
        userInfo.getUserbaseInfo();
        userInfo.getUserDetailInfo();

    }
}

class UserInfo{
    public void getUserbaseInfo(){
        System.out.println("获取用户基础信息");
    }

    public void getUserDetailInfo(){
        System.out.println("获取用户详细信息");
    }
}