Head first design patterns

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Chapter 1. Welcome to Design Patterns

Table of Contents
Chapter 1. Welcome to Design Patterns....................................................... 1
Section 1.1. It started with a simple SimUDuck app....................................................................................................................... 2
Section 1.2. But now we need the ducks to FLY............................................................................................................................. 3
Section 1.3. But something went horribly wrong........................................................................................................................... 4
Section 1.4. Joe thinks about inheritance....................................................................................................................................... 5
Section 1.5. Sharpen your pencil..................................................................................................................................................... 5
Section 1.6. How about an interface?............................................................................................................................................. 6
Section 1.7. What would you do if you were Joe?........................................................................................................................... 7
Section 1.8. The one constant in software development................................................................................................................ 8
Section 1.9. Sharpen your pencil.................................................................................................................................................... 8
Section 1.10. Zeroing in on the problem......................................................................................................................................... 9
Section 1.11. Separating what changes from what stays the same............................................................................................... 10
Section 1.12. Designing the Duck Behaviors.................................................................................................................................. 11
Section 1.13. Implementing the Duck Behaviors.......................................................................................................................... 13
Section 1.14. There are no Dumb Questions................................................................................................................................. 14
Section 1.15. Sharpen your pencil.................................................................................................................................................. 14
Section 1.16. Integrating the Duck Behavior................................................................................................................................. 15
Section 1.17. More Integration...................................................................................................................................................... 16
Section 1.18. Testing the Duck code.............................................................................................................................................. 18
Section 1.19. Setting behavior dynamically.................................................................................................................................. 20
Section 1.20. The Big Picture on encapsulated behaviors............................................................................................................ 22
Section 1.21. HAS-A can be better than IS-A................................................................................................................................ 23
Section 1.22. Speaking of Design Patterns................................................................................................................................... 24
Section 1.23. Design Puzzle........................................................................................................................................................... 25
Section 1.24. Overheard at the local diner.................................................................................................................................... 26

Section 1.25. Overheard in the next cubicle.................................................................................................................................. 27
Section 1.26. The power of a shared pattern vocabulary............................................................................................................. 28
Section 1.27. How do I use Design Patterns?............................................................................................................................... 29
Section 1.28. There are no Dumb Questions................................................................................................................................ 29
Section 1.29. Skeptical Developer-Friendly Patterns Guru......................................................................................................... 30
Section 1.30. Tools for your Design Toolbox................................................................................................................................ 32
Section 1.31. Design Puzzle Solution............................................................................................................................................ 34
Section 1.32. Solutions.................................................................................................................................................................. 35

Chapter 1. Welcome to Design Patterns
Head First Design Patterns By Eric Freeman, Elisabeth Freeman, Bert Bates, Kathy Sierra
Prepared for Ann Cherkis, Safari ID:
ISBN: 0596007124 Publisher: O'Reilly
Print Publication Date: 2004/10/25
User number: 1673621 Copyright 2008, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.

www.it-ebooks.info


Chapter 1. Welcome to Design Patterns

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Page 1

Intro to Design Patterns

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Chapter 1. Welcome to Design Patterns
Head First Design Patterns By Eric Freeman, Elisabeth Freeman, Bert Bates, Kathy Sierra
Prepared for Ann Cherkis, Safari ID:
ISBN: 0596007124 Publisher: O'Reilly
Print Publication Date: 2004/10/25
User number: 1673621 Copyright 2008, Safari Books Online, LLC.

This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.

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Chapter 1. Welcome to Design Patterns

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Chapter 1. Welcome to Design Patterns
Head First Design Patterns By Eric Freeman, Elisabeth Freeman, Bert Bates, Kathy Sierra
Prepared for Ann Cherkis, Safari ID:
ISBN: 0596007124 Publisher: O'Reilly
Print Publication Date: 2004/10/25
User number: 1673621 Copyright 2008, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.

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Chapter 1. Welcome to Design Patterns

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Chapter 1. Welcome to Design Patterns
Head First Design Patterns By Eric Freeman, Elisabeth Freeman, Bert Bates, Kathy Sierra

Prepared for Ann Cherkis, Safari ID:
ISBN: 0596007124 Publisher: O'Reilly
Print Publication Date: 2004/10/25
User number: 1673621 Copyright 2008, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.

www.it-ebooks.info


Chapter 1. Welcome to Design Patterns

Return to Table of Contents

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