1. CSE 143: Computer Programming II
Ruth E. Anderson
Autumn 2009

2. Today’s Outline Introductions Administrative Info Abstraction Objects
09/30/09
CSE Introduction

3. Me (Ruth Anderson)
Grad Student at UW (Programming Languages, Compilers, Parallel Computing)
Taught Computer Science at the University of Virginia for 5 years
Grad Student at UW (Educational Technology, Pen Computing)
Defended my PhD in fall 2006
Computing and the Developing World
Recently taught cse142, data structures, compilers, programming languages, architecture
09/30/09
CSE Introduction

4. “Suggested” Activities
Tonight: Install Java, JGrasp, etc.
Thursday: Go to Section!
Information Sheet: bring to section
Friday:
Review CSE142 material
Assignment #1 will be posted on Friday
09/30/09
CSE Introduction

5. Information Sheet Bring to Section on Thursday:
Name
Quiz Section (AB, AC, etc)
address
Year (Fresh, Soph, etc.)
Major
When took CSE 142
Hometown
Interesting Fact or what I did over summer/break.
09/30/09
CSE Introduction

6. Today’s Outline Introductions Administrative Info Abstraction Objects
09/30/09
CSE Introduction

7. Review

8. Abstraction Hiding details Makes our life easier
Tool for managing complexity
09/30/09
CSE Introduction

9. Today’s Outline Introductions Administrative Info Abstraction Objects
09/30/09
CSE Introduction

10. Ruth’s Stereo Receiver (is broken)
Photo credits:

11. Photo credits: http://audio.mm-team.com/

12. Photo credits: http://audio.mm-team.com/

13. Photo credits: http://audio.mm-team.com/

14. Today’s Outline Introductions Administrative Info Abstraction Objects
09/30/09
CSE Introduction

15. An object encapsulates state and behavior.
Objects
An object encapsulates state and behavior.
09/30/09
CSE Introduction

16. An object encapsulates state and behavior.
- What an object knows
- Data, usually in the form of variables
Stereo Receiver state?
09/30/09
CSE Introduction

17. An object encapsulates state and behavior.
- What an object does
- Actions, usually in the form of methods
Stereo Receiver behavior?
09/30/09
CSE Introduction

18. Two views of an Object Client view: Implementer view:
Knows what an object can do
Stereo Receiver client view
Can turn stereo on/off, select station, increase volume, etc.
Implementer view:
Knows exactly how an object works
Stereo Receiver implementer view
Can see (and modify) all the internal circuitry
09/30/09
CSE Introduction

19. An object encapsulates state and behavior
Encapsulation:
hiding the implementation details from clients
The client should only know what is necessary to use the object
The client does not need to know how the object has been implemented
How is the Stereo Receiver encapsulated?
09/30/09
CSE Introduction

20. “Suggested” Activities
Tonight: Install Java, JGrasp, etc.
Thursday: Go to Section!
Information Sheet: bring to section
Friday:
Review CSE142 material
Assignment #1 will be posted on Friday
09/30/09
CSE Introduction