1. Welcome back to Software Development!

2. Review – Class Members Do review slides
Finish MenuOption method project
Instances and static
Create UserInput class

3. Review – Class Members
What are the three main types of class members?

4. Review – Class Members What are the three main types of class members?
Methods

5. Review – Class Members What are the three main types of class members?
Methods – class algorithms

6. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’

7. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’
Fields

8. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’
Fields – class variables any method of the class can use

9. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’
Fields – class variables any method of the class can use
The data or information the class uses to do its job

10. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’
Fields – class variables any method of the class can use
The data or information the class uses to do its job
Properties

11. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’
Fields – class variables any method of the class can use
The data or information the class uses to do its job
Properties – “smart fields”

12. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’
Fields – class variables any method of the class can use
The data or information the class uses to do its job
Properties – “smart fields”
Methods that look like fields…you can use them almost like variables

13. Review – Class Members What are the three main types of class members?
Methods – class algorithms
The actual code that does the work – the ‘algorithm’
Fields – class variables any method of the class can use
The data or information the class uses to do its job
Properties – “smart fields”
Methods that look like fields…you can use them almost like variables
They “protect” the class variables (fields)

14. Review - Scope

15. Review - Scope
What does scope mean?

16. Review - Scope What does scope mean?
The section of code a variable can be used in

17. Review - Scope What does scope mean?
The section of code a variable can be used in
Defined by the current block { }

18. Review - Scope What does scope mean?
The section of code a variable can be used in
Defined by the current block { }
Inner blocks can see variables from outer blocks

19. Review - Scope What does scope mean?
The section of code a variable can be used in
Defined by the current block { }
Inner blocks can see variables from outer blocks
Outer blocks can not see variables from inner blocks

20. Review – Scope Modifiers

21. Review – Scope Modifiers
We will call them access modifiers

22. Review – Scope Modifiers
We will call them access modifiers
What are access modifiers?

23. Review – Scope Modifiers
We will call them access modifiers
What are access modifiers?
Keywords public and private

24. Review – Scope Modifiers
We will call them access modifiers
What are access modifiers?
Keywords public and private
Control who has access to the members of a class

25. Review – Scope Modifiers
We will call them access modifiers
What are access modifiers?
Keywords public and private
Control who has access to the members of a class
public :

26. Review – Scope Modifiers
We will call them access modifiers
What are access modifiers?
Keywords public and private
Control who has access to the members of a class
public : everyone has access and can change

27. Review – Scope Modifiers
We will call them access modifiers
What are access modifiers?
Keywords public and private
Control who has access to the members of a class
public : everyone has access and can change
private :

28. Review – Scope Modifiers
We will call them access modifiers
What are access modifiers?
Keywords public and private
Control who has access to the members of a class
public : everyone has access and can change
private : only members of same class have access and can change

29. The real, the original, the authentic Nestle Toll House Chocolate Chip Cookie Recipe
2 1/4 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon salt
1 cup (2 sticks, 1/2 pound) butter, softened
3/4 cup granulated [white] sugar
3/4 cup packed brown sugar
1 teaspoon vanilla extract
2 eggs
2 cups (12-ounce package) NESTLE TOLL HOUSE Semi-Sweet Chocolate Morsels
1 cup chopped nuts
COMBINE flour, baking soda and salt in small bowl. Beat butter, granulated sugar, brown sugar and vanilla in large mixer bowl. Add eggs one at a time, beating well after each addition; gradually beat in flour mixture. Stir in morsels and nuts. Drop by rounded tablespoon onto ungreased baking sheets.
BAKE in preheated 375-degree [Fahrenheit] oven for 9 to 11 minutes or until golden brown. Let stand for 2 minutes; remove to wire racks to cool completely.
PAN COOKIE VARIATION: PREPARE dough as above. Spread into greased 15"x10" jelly-roll pan. Bake in preheated 375-degree [Fahrenheit] oven for 20 to 25 minutes or until golden brown. Cool in pan on wire rack.
FOR HIGH ALTITUDE BAKING (>5,200 feet): INCREASE flour to 2 1/2 cups; add 2 teaspoonfuls water with flour; reduce both granulated sugar and brown sugar to 2/3 cup each. Bake at 375 degrees Fahrenheit, drop cookies for 8 to 10 minutes and pan cookies for 17 to 19 minutes
If I give this recipe to you, what good is it?
Can you eat this recipe?
No, you have to make a cookie from the recipe…

30. Instance

31. Instance
A class is like a recipe

32. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)

33. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie

34. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie
The cookie is an “instance” of the recipe

35. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie
The cookie is an “instance” of the recipe
You have “created” or “declared” a cookie from the recipe

36. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie
The cookie is an “instance” of the recipe
You have “created” or “declared” a cookie from the recipe
Now you can “use” the cookie

37. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie
The cookie is an “instance” of the recipe
You have “created” or “declared” a cookie from the recipe
Now you can “use” the cookie
You have to create an instance of a class to use it…

38. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie
The cookie is an “instance” of the recipe
You have “created” or “declared” a cookie from the recipe
Now you can “use” the cookie
You have to create an instance of a class to use it…
Except…

39. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie
The cookie is an “instance” of the recipe
You have “created” or “declared” a cookie from the recipe
Now you can “use” the cookie
You have to create an instance of a class to use it…
Except…Unless…

40. Instance A class is like a recipe
You can’t eat the recipe (unless you like paper…)
You have to make a cookie
The cookie is an “instance” of the recipe
You have “created” or “declared” a cookie from the recipe
Now you can “use” the cookie
You have to create an instance of a class to use it…
Except…Unless…the some part of the class is useful all by itself…

41. The Coffee Pot Show coffee pot Ask what its function is Make coffee
Ask what you have to do to use that function
Add water and coffee
Can you make the coffee if you don’t add water and coffee grounds?

42. The Coffee Pot
Think of a coffee pot as an object…

43. The Coffee Pot
Think of a coffee pot as an object…a class

44. The Coffee Pot Think of a coffee pot as an object…a class
It has one method

45. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()

46. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields

47. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater

48. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater
2) amountOfCoffeeGrounds

49. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater
2) amountOfCoffeeGrounds
The method needs the fields to work

50. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater
2) amountOfCoffeeGrounds
The method needs the fields to work
Does this class have any use not requiring the fields?

51. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater
2) amountOfCoffeeGrounds
The method needs the fields to work
Does this class have any use not requiring the fields?
The glass pot can carry water…

52. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater
2) amountOfCoffeeGrounds
The method needs the fields to work
Does this class have any use not requiring the fields?
The glass pot can carry water…acts as a water pitcher

53. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater
2) amountOfCoffeeGrounds
The method needs the fields to work
Does this class have any use not requiring the fields?
The glass pot can carry water…acts as a water pitcher
We have a new method

54. The Coffee Pot Think of a coffee pot as an object…a class
It has one method – MakeCoffee()
It has two fields
1) amountOfWater
2) amountOfCoffeeGrounds
The method needs the fields to work
Does this class have any use not requiring the fields?
The glass pot can carry water…acts as a water pitcher
We have a new method – UseAsWaterPitcher()

55. Static Methods

56. Static Methods
Some methods do not need to use any of the class fields

57. Static Methods Some methods do not need to use any of the class fields
These can be static methods

58. Static Methods Some methods do not need to use any of the class fields
These can be static methods
Most methods do need to use some of the class fields

59. Static Methods Some methods do not need to use any of the class fields
These can be static methods
Most methods do need to use some of the class fields
These can not be static methods

60. Static Methods

61. Static Methods
static

62. Static Methods
static
The keyword static means it doesn’t use any of the class fields

63. Static Methods
static
The keyword static means it doesn’t use any of the class fields
You can use static methods without creating an instance of the class

64. Non-static Methods

65. Non-static Methods
To use methods of a class that are not static…

66. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class

67. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new

68. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example:

69. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…

70. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum;

71. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum;
Variable name

72. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum;
Variable type
Variable name

73. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum;
Variable type
Variable name
Declaring a variable
named rndNum of
type Random

74. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum;
Variable type
Variable name
Declaring a variable
named rndNum of
type Random
You have created the “recipe” … you haven’t baked the cookie yet

75. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum = new Random();

76. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum = new Random();
Create the recipe

77. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum = new Random();
Create the recipe
Bake the cookie…
…create an instance of the
class Random as a variable

78. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum = new Random();
Create the recipe
Bake the cookie…
…create an instance of the
class Random as a variable
Keyword new is used to create an instance of a class

79. Non-static Methods To use methods of a class that are not static…
You must create an instance of the class … as a variable using keyword new
Example: the class Random…
Random rndNum = new Random();
int a = rndNum.Next(1, 20);

80. Creating a class

81. Creating a class
class nameOfClass

82. Creating a class class nameOfClass {
members of the class (fields, properties, methods) }

83. Creating a class class nameOfClass {
members of the class (fields, properties, methods) }