前言 在上一个博客中我们介绍了Strategy模式,它是行为型模式麾下的一员大将.那么本博客我们来学习一下行为型模式麾下的另一员大将Observer模式. 思考题 老套路,先来思考下面的问题: 问题:思考报纸订阅的问题,有一个体育报社每天都会有新的体育报道,关注体育新闻的用户会获取每天的报道 首先,我们还是来看一看不使用设计模式的代码: SportNews.java: public class SportNews { private String context; //用户获取新闻 public…

1. Brief 一直对Observer Pattern和Pub/Sub Pattern有所混淆,下面打算通过这两篇Blog来梳理这两种模式.若有纰漏请大家指正. 2. Use Case 首先我们来面对一个老到跌渣的故事,并以从未听说过Observer Pattern为前提. 假设要设计一个新闻订阅系统,新闻分为商业.体育和八卦3种,而查收终端有PC.移动终端等,后续还不断增加新闻种类和查收终端. 需求如上,下面我们根据OOD的方式来构建概念模型. 新闻 <- 分类新闻 终端 <- 分类终端…

The Observer Pattern The Observer is a design pattern where an object (known as a subject) maintains a list of objects depending on it (observers), automatically notifying them of any changes to state. When a subject needs to notify observers about s…

回到占占推荐博客索引 设计模式(Design pattern)与其它知识不同,它没有华丽的外表,没有吸引人的工具去实现,它是一种心法,一种内功,如果你希望在软件开发领域有一种新的突破,一个质的飞越,那么,设计模式应该是你的必修之路!设计模式可以提高软件的扩展性,代码的健壮性和重复利用性,设计模式是实现软件工程四大原则( 开闭原则, 里氏代换原则,依赖倒转原则,接口隔离原则)的前提和基础! 下面是我的文章系列<说说设计模式>的目录 第一部分 创建型模式篇 说说设计模式~单件模式(Singleto…

Bridge Pattern, Composite Pattern, Decorator Pattern, Facade Pattern, COR Pattern, Proxy Pattern, template Pattern, MVC. Updated with the explanation of Composite pattern, Decorator Pattern and Template Pattern. Design Pattern Interview Question - Pa…

Interpeter , Iterator , Mediator , Memento and Observer design patterns. (I) what is Interpreter pattern? (B) Can you explain iterator pattern? (A) Can you explain mediator pattern? (I) Can you explain memento pattern? (B) Can you explain observer pa…

Factory, Abstract factory, prototype pattern (B) What are design patterns? (A) Can you explain factory pattern? (I) Can you explain abstract factory pattern? (I)Can you explain builder pattern? (I) Can you explain prototype pattern? (A) Can you expla…

Q: What is a Design Pattern? A: Design Patterns represent solutions to problems what arise when developing software within a particular context. Each pattern describes a problem which occurs over and over again in our environment, and then describes…

Instead of defining what is design pattern lets define what we mean by design and what we mean by pattern. According to me design is blue print or sketch of something so it can be defined as creation of something in mind. Moving to pattern, we can de…

java设计模式大全 Design pattern samples in Java(最经典最全的资料) 2015年06月19日 13:10:58 阅读数:11100 Design pattern samples in Java. Build status: Introduction Design patterns are formalized best practices that the programmer can use to solve common problems when desi…