1. CSE 1030: Aggregation and Composition
Mark Shtern

2. Summary
Aggregation
Constructors
Accessor/Mutators
Collections

3. Collections Copy Contractor ArrayList copy= new ArrayList();
Alias
this.setBooks(library.books)
Shallow Copy
this.setBooks(new ArrayList(library.getBooks()))
Deep Copy
ArrayList copy= new ArrayList();
for (Book book:books)
copy.add(new Book(book));
this.setBooks(copy);

4. What is Composition
Object Composition is a way to combine simple object into more complex ones
Composite objects are usually expressed by means of references from one object to another
Exactly like Aggregation except that the lifetime of the 'part' is controlled by the 'whole'

5. Is it composition?
Carburetor carburetor = new Carburetor(); car = new Car(carburetor);
Answer: NO

6. Is it composition?
Carburetor carburetor = new Carburetor(); car = new Car(carburetor);
Answer: Yes

7. Is it possible? Answer: NO
Carburetor carburetor = new Carburetor(); car = new Car(carburetor); Carburetor carburetor1 = carburetor; carburetor = car.getCarburetor();
Answer: NO

8. Is composition correctly implemented?
Carburetor carburetor = new Carburetor(); car = new Car(carburetor); carburetor = car.getCarburetor();
Answer:
When carburetor is immutable
object then yes, otherwise no

9. Is composition correctly implemented?
Carburetor carburetor = new Carburetor(); car = new Car(carburetor); carburetor = car.getCarburetor();
Answer: Yes

10. UML Diagram public Car { private Carburetor carburetor; Car () {
carburetor = new Carburetor(); }

11. Constructor
Carburetor carburetor = new Carburetor(); car = new Car(carburetor); public Car(Carburetor carburetor) { this.setCarburator(carburetor); }

12. Method section Accessor public Carburetor getCarburetor() {
return new Carburetor (this.carburator); }

13. Method section Mutator public boolean setCarburetor(Carburetor c) {
// validation section
// returns false if input is invalid
this.carburator = new Carburetor(c);
return true; }

14. Implementing Inheritance

15. Ex601
Develop an directory application which stores personal information about students, faculty and staff. In addition to the information commonly found in telephone books, your directory contains the following data
Student  Major
Staff and Faculty  Room
Faculty Office hours
Staff Title

16. Design