Glass V4, More Info For Your Solution

Size: px

Start display at page:

Download "Glass V4, More Info For Your Solution"

Walter Daniels
5 years ago
Views:

1 Glass V4, More Info For Your Solution Mike 1

2 Glass V4, More Info For Your Solution Modeling Mike 2

3 Hello! Mike Edwards 3

4 Modelling NOT THIS KIND 4

5 Modelling THIS KIND 5

6 Modelling Different Patterns Common Mistakes Techniques 6

7 Common Patterns Active Record Data Mapping Wrapping 7

8 Active Record Pattern In software engineering, the active record pattern is an architectural pattern found in software that stores in-memory object data in relational databases. The interface of an object conforming to this pattern would include functions such as Insert, Update, and Delete. - Wiki, Martin Fowler 8

9 Active Record Pattern The Example 9

10 Active Record Pattern - Pro s Simple to use: 10

11 Active Record Pattern - Pro s Simple to pass around: 11

12 Active Record Pattern - Con s Hidden side effects: Surprise!! Pointless 12

13 Active Record Pattern - Cons Coupled to data source: 13

14 Active Record Pattern - Con s Complex: 14

15 Active Record Pattern - Con s Hard to test: How do we mock this?? Ask the FakeDB Guys 15

16 Data Mapper Pattern Data Mapper is a Data Access Layer that performs bidirectional transfer of data between a persistent data store (often a relational database) and an in memory data representation (the domain layer). The goal of the pattern is to keep the in memory representation and the persistent data store independent of each other and the data mapper itself. - Wiki, Martin Fowler 16

17 Data Mapper Pattern The Example 17

18 Data Mapper Pattern The Example 18

19 Data Mapper Pattern The Example 19

20 Data Mapper Pattern Simple Models 20

21 Data Mapper Pattern - Pro s Easy Testing 21

22 Data Mapper Pattern - Pro s Clear Separation My World Their World 22

23 Data Mapper Pattern - Pro s Store Anywhere 23

24 Data Mapper Pattern - Pro s Clear Control Hello!! 24

25 Data Mapper Pattern - Con s Map Unused Data 25

26 Data Mapper Pattern - Con s Expensive Upfront 26

27 Data Mapper Pattern - Con s Disconnection from source Where the hell did you come from? 27

28 Wrappers Models Wraps the underlying data source and converts the data on demand. The internal model contains a reference to the original data source which it uses to perform data conversion. 28

29 Wrappers Models 29

30 Wrappers Models - Pro s Cheap Up Front No work done here! Only accessed properties require conversion. 30

31 Wrappers Models - Pro s Hidden State Changes What happens if this changes 31

32 Wrappers Models - Pro s Hidden State Changes Are these the same? 32

33 Wrappers Models - Con s Testing Difficulty Can t test because of this. Need to understand this Have to write data conversion code 33

34 Wrappers Models - Meet my partner Coupling I ask for this 34

35 Wrappers Models - Meet my partner Coupling I get this 35

36 Common Problems Anemic domain model Bloated domain model Skinny domain model Indiscreet domain model 36

37 Anemic Domain Model Anemic domain model is the use of a software domain model where the domain objects contain little or no business logic (validations, calculations, business rules etc). - Wiki, Martin Fowler 37

38 Anemic Domain Model - Example Feed Me!! 38

39 Anemic Domain Model 39

40 Bloated Domain Model A Bloated Domain Model is the use of a software domain model that contains a large number of properties that are never access or required by the application. - Mike E 40

41 Bloated Domain Model 41

42 Bloated Domain Model Fixed 42

43 Skinny Domain Model A Skinny Domain Model is the use of a software domain model that contains one or very few properties. - Mike 43

44 Skinny Domain Model Skinny Domain model 44

45 Skinny Domain Model Fixed USE THE RAW API! 45

46 Indiscreet Domain Model A Indiscreet Domain Model is the use of a software domain model that exposes all it s properties publically even if they should or should not be accessed by external code. - Mike E 46

47 Indiscreet Domain Model 47

48 Indiscreet Domain Model Fixed 48

49 Techniques Interface Models Template Models Rendering Models MVC MVP 49

50 Interface Models Domain models defined using interfaces only. Interface are dynamically implemented at run time using a proxy framework. 50

51 Interface Models 51

52 Interface Models Multiple Inheritance Very little code Often Anemic Indiscreet 52

53 Interface Models Spoofing Logic 53

54 Template Models 54

55 Template Models Code generation friendly Easy to sync Bloated Indiscreet Anemic 55

56 Rendering Models 56

57 Rendering Models Use case specific Minimum number of properties Custom methods Model explosion Magic Properties Problem Skinny 57

58 MVC Models Model view controller (MVC) is a software architectural pattern for implementing user interfaces. It divides a given software application into three interconnected parts, so as to separate internal representations of information from the ways that information is presented to or accepted from the user. - - Wiki 58

59 MVC Models What do we pass to the view? 59

60 MVC Models The View Model Explicitly defines the contract Easy to expand Use convention Separates Domain from View 60

61 MVC Models Easy to find 61

62 MVC Models Easy to identify! 62

63 And don t forget MVP! MVP is a user interface architectural pattern engineered to facilitate automated unit testing and improve the separation of concerns in presentation logic. - Wiki 63

64 MVP 64

65 MVP is similar to MVC 65

66 MVP or MVC? 66

67 Finished!! Questions? 67

68 Find Me: Mike Edwards 68

69 Thank you [Reserved for sponsor logo s] 69

DESIGN PATTERNS MOCK TEST DESIGN PATTERNS MOCK TEST III

DESIGN PATTERNS MOCK TEST DESIGN PATTERNS MOCK TEST III http://www.tutorialspoint.com DESIGN PATTERNS MOCK TEST Copyright tutorialspoint.com This section presents you various set of Mock Tests related to Design Patterns Framework. You can download these sample