comp 110 classes tabitha peck m.s. february 20, 2008 mwf 3-3:50 pm philips 367 1
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COMP 110Classes
Tabitha Peck M.S.
February 20, 2008
MWF 3-3:50 pm
Philips 367
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Announcements Lab 4 Due Friday
Office Hours - Today after Class Help with loops Help with Lab 4
Jason Jerald
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Participants Needed for Virtual RealityMotion Perception in Virtual Environments During Head Turns
What you get Learn about programming in a research environment Learn what grad students are doing in computer science Help contribute to improving virtual reality technology Earn real money
The task select which of two presentations you believe contains scene motion 600-1000 trials Earn $.05 for each correct selection - Do the math! Study takes 3-5 Hours
For more info Filling out form is not committing Name Preferred contact (email or phone) Preferred hours
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Questions?
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Today in COMP 110
Worksheet Review (quick)
Debugger
Classes
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Debugger
What is the length?
t h i s i s a s t r i n g
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
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Classes
wagTail
Terrier
bark
Retriver
beg
Shepard
DogClass
Object
Methods
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Classes
nextInt
keyboard
next
sc
nextDouble
s
ScannerClass
Object
Methods
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Classes
getMajor
Jack
calcGpa
Amanda
increaseYear
Spencer
StudentClass
Object
Methods
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UML Diagram
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Class Name: Student
Class YearGPAMajorCreditsGPA sum
+ getMajor+ printData+ increaseYear
How: increase year by 1+ calcGPA
How: average grades
UML DiagramClass Name: Student
Class Year (int)GPA (double)Major (String)Credits (int)GPA sum (double)
+ getMajor(): String+ increaseYear(): void+ calcGPA(double grade): void+ printData(): void
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Class File
Each class in SEPARATE file Create instance of Class in main You will have TWO (or more) files!! Call methods in main You must run your file from main!!!!!!!
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Create instance of Class in main
public class StudentStats{
public static void main(String[] args){
// instantiating object of type student Student s1 = new Student();
}} Class Object Class
Different NameFrom Class
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Create Class in Separate File
public class Student{
//everything in your class goes here
} Save as Student.java
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UML DiagramClass Name: Student
Class Year (int)GPA (double)Major (String)Credits (int)GPA sum (double)
+ getMajor(): String+ increaseYear(): void+ calcGPA(double grade): void+ printData(): void
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Data (in your class file)
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public int classYear;private double gpa;public String major;private int credits = 0;private double gpaSum; private - only access variables INSIDE
your class public - access to variables OUTSIDE your
class
Public Variables
Student s1 = new Student();
s1.classYear = 2;
classYear is a variable NOT a method Don’t use ()
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Private Variables
Variables you do not want a user to manipulate
GPA - calculate GPA in your class Don’t want user to reset the value
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UML DiagramClass Name: Student
Class Year (int)GPA (double)Major (String)Credits (int)GPA sum (double)
+ getMajor(): String+ increaseYear(): void+ calcGPA(double grade): void+ printData(): void
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Method getMajor
/*getMajor
Input: none
Return: major*/
public String getMajor()
{ return major;
}
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Return type
Type String
Calling method getMajor
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public static void main(String[] args){ Student s1 = new Student(); s1.major = “English”; String m = s1.getMajor(); System.out.print(m);}
UML DiagramClass Name: Student
Class Year (int)GPA (double)Major (String)Credits (int)GPA sum (double)
+ getMajor(): String+ increaseYear(): void+ calcGPA(double grade): void+ printData(): void
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Method increaseYear/*increaseYearInput: noneDescription: increase student year by oneReturn: none*/
public void increaseYear(){ if (classYear < 4) classYear++;
}
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Calling method increaseYear
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public static void main(String[] args){ Student s1 = new Student(); s1.classYear = 2; s1.increaseYear(); // classYear = 3 s1.increaseYear(); // classYear = 4 s1.increaseYear(); // classYear = 4}
UML DiagramClass Name: Student
Class Year (int)GPA (double)Major (String)Credits (int)GPA sum (double)
+ getMajor(): String+ increaseYear(): void+ calcGPA(double grade): void+ printData(): void
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Method calcGpa/*calcGpaInput: grade(double)Description: update credits and gpaSum
calculate GPAReturn: none*/
public void calcGpa(double grade){ credits++; //increase number of credits gpaSum = gpaSum + grade; gpa = gpaSum / credits;}
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Calling method calcGpa
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public static void main(String[] args){ Student s1 = new Student(); s1.calcGpa(3.5); //gpa = 3.5 s1.calcGpa(2.4); // gpa = 2.95 }
UML DiagramClass Name: Student
Class Year (int)GPA (double)Major (String)Credits (int)GPA sum (double)
+ getMajor(): String+ increaseYear(): void+ calcGPA(double grade1, double grade2): void+ printData(): void
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Method printData/*printDataInput: noeDescription: print instance variablesReturn: none*/
public void printData(){DecimalFormat df = new DecimalFormat("0.00"); System.out.print("Major: " + major + ”\nClass year: " + classYear + ”\nGPA: " + df.format(gpa));
}
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Code on Website
Open the code
Save the code
Understand the code
Run the code
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Friday
Lab 5
Classes
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