Building one's own iterator is a great exercise to see how to separate the responsibilities of the various parts of the code. In this video, learn how to build an iterator for an array.
- [Instructor] Let's take a look at the class diagram … for the iterator pattern and then we'll see … how to implement it for the menus. … In our example, the aggregate object is a menu … which uses an array list or an array … to store the menu items. … We have an aggregate interface … and a concrete aggregate class … that implements that interface, … providing a method, create iterator, … that creates and returns an iterator object. … The client stores that iterator … and then, when it needs to iterate over the items … in the aggregate object, it can use the methods … defined by the iterator interface to do so. … The hasNext method figures out if there are more items … to iterate over and the next method just returns … the next item. … Here's how we'll design our menus example … to use the iterator pattern. … Our aggregate object will be the menu. … We'll add a menu interface that defines one method, … create iterator, and both the pancake house menu … and the diner menu will implement that menu interface. …
- What are design patterns?
- Encapsulating code that varies with the Strategy pattern
- The limitations of inheritance
- Using the Adapter pattern
- Implementing the Observer pattern
- Extending behavior with composition and the Decorator pattern
- Encapsulating iteration with the Iterator pattern
- Object creation with the Factory Method pattern
- Using design principles to guide your object-oriented design
Skill Level Intermediate
1. Design Patterns
2. The Strategy Pattern
3. The Adapter Pattern
4. The Observer Pattern
Using the Observer pattern2m 23s
5. The Decorator Pattern
6. The Iterator Pattern
7. The Factory Patterns
- Mark as unwatched
- Mark all as unwatched
Are you sure you want to mark all the videos in this course as unwatched?
This will not affect your course history, your reports, or your certificates of completion for this course.Cancel
Take notes with your new membership!
Type in the entry box, then click Enter to save your note.
1:30Press on any video thumbnail to jump immediately to the timecode shown.
Notes are saved with you account but can also be exported as plain text, MS Word, PDF, Google Doc, or Evernote.