Decorator uses Delegation, but in a very specific way. Delegation (or composition) is not as much a pattern as a general way to build complex behavior by coordinating use of several other objects. It’s often used in a set or static way. By “set or static” I mean something like this: class Delegator { private … Read more
It’s a Safari mobile bug/feature : click events won’t bubble all the way up to body. Adding onclick=”” is a known workaround, but IMHO it’s easier to attach your listener on a first child of <body>. See: http://www.quirksmode.org/blog/archives/2010/09/click_event_del.html
A @link or @see tag would be appropriate here. If you’re wrapping the method, it must provide distinctive behavior which makes it unsuitable for overloading or otherwise.
Preface: POP and OOP are not mutually exclusive. They’re design paradigms that are greatly related. The primary aspect of POP over OOP is that is prefers composition over inheritance. There are several benefits to this. In large inheritance hierarchies, the ancestor classes tend to contain most of the (generalized) functionality, with the leaf subclasses making … Read more
Delegates send messages to you. For example: if you use the accelerometer delegate, you will get messages about the accelerometer. If you use that new neutrino-detection delegate, you will get messages about any neutrinos detected in the area. If you use PopUps, PopUps send you messages. And the way that is done, is with the … Read more
Delegation is not exactly a ‘design pattern’ in the sense used in the GoF book. It is useful in a number of scenarios, and is a base for other patterns when you want to perform some additional actions before/after you delegate (that’s the Decorator pattern, but it’s based on delegation). For example, Collections.synchronizedList(..) creates a … Read more
When you want to “copy”/Expose the base class’ API, you use inheritance. When you only want to “copy” functionality, use delegation. One example of this: You want to create a Stack out of a List. Stack only has pop, push and peek. You shouldn’t use inheritance given that you don’t want push_back, push_front, removeAt, et … Read more
Delegation public class A { private B b = new B(); public void methodA() { b.methodB(); } } When clients of A call methodA, class A delegates the call to B‘s methodB. Rationale. Class A exposes behaviours that belong elsewhere. This can happen in single-inheritance languages where class A inherits from one class, but its … Read more
As said, there’s no way. However, a bit decent IDE can autogenerate delegate methods. For example Eclipse can do. First setup a template: public class MultipleInterfaces implements InterFaceOne, InterFaceTwo { private InterFaceOne if1; private InterFaceTwo if2; } then rightclick, choose Source > Generate Delegate Methods and tick the both if1 and if2 fields and click … Read more
Now it is possible delegate OpenID to your Google account (not Google Apps). No, this is not using the demo OpenID provider using App Engine. This is your REAL Google account! First you need to enable your Google Profiles. Try to view your profile and edit it, there should be an option to set your … Read more