FunZONE-4-Geeks

Observer Pattern The observer pattern defines a one to many relation between objects so that when one object changes state, all of its dependent or related objects get notified automatically Real Life Example: Group Chat is a real life example of observer pattern. Whenever someone type some text in text button and hit send button. Every member get notified that someone texted in group. Java Code Example: public interface Subject { void register(Observer observer); void remove(Observer observer); void notifyRespectedObserver(String msg); } public interface Observer { void update(String msg); String write(String msg); String getName(); } public class Console implements Subject { public List memberList; public Console(){ memberList = new LinkedList (); } public void register(Observer observer){ memberList.add(observer); } public void remove(Observer observer){ memberList.remove(observer); } public void notifyRespectedObserver(String msg){ for...

                      I n software engineering, a design pattern is a general reusable solution to a commonly occurring problem within a given context in software design. A design pattern is not a finished design that can be transformed directly into the source or machine code. It is a description or template for how to solve a problem that can be used in many different situations. - Wiki To explore the various kind of Design Patterns follow the below links. ----------------------------------------------------------------------------------------------------------------- Observer Pattern ----------------------------------------------------------------------------------------------------------------- Proxy Pattern ----------------------------------------------------------------------------------------------------------------- Builder Pattern ------------------------...