answer the questions through out tthe code ;

public int compareTo(Student rhs) {

//10 what does the compareTo return?

//11 What is this compareTo method for?

if (lastName.compareTo(rhs.getLastName()) < 0){

return -1;

}

if (lastName.compareTo(rhs.getLastName()) > 0){

return 1;

}

if (firstName.compareTo(rhs.getFirstName()) < 0){

return -1;

}

if (firstName.compareTo(rhs.getFirstName()) > 0){

return 1;

}

return 0;

}

}

roster:

package SimpleRosterPackage;

import java.util.TreeSet;

//12 What is the purpose for this class?

public class Roster {

//13 What is a TreeSet?

//14 What is for?

private TreeSet students;

private String className;

public Roster (String cn) {

className = cn;

students = new TreeSet();

}

public String toString () {

String toReturn = className + ": ";

// Waht is the following for loop for?

for (Student s : students) {

toReturn += s.toString() + " ";

}

return toReturn;

}

public Student getStudent (Student tester) {

//15 What does the floor method of the TreeSet Class do?

Student toReturn = students.floor(tester);

if (toReturn == null)

return null;

//16 Hard question: how are we comparing Students to test if they are equal?

if (toReturn.equals(tester))

return toReturn;

return null;

}

public void addStudent (Student s) {

//17 What does this addStudent method do?

students.add(s);

}

}

rostertester:

package SimpleRosterPackage;

public class RosterTester {

public static void main(String[] args) {

// create a empty list of students

Roster csci3381 = new Roster ("OO with Java");

// create a single student and print

Student aStudent = new Student("Mouse","Micky");

aStudent.addGrade(95);

System.out.println("printing a single student");

System.out.println(aStudent);

System.out.println();

// add the previously created student to this collection of students

csci3381.addStudent(aStudent );

//18 What do the following lines of code do?

csci3381.addStudent(new Student("Mouse","Minnie") );

csci3381.addStudent(new Student("Duck","Daffy") );

csci3381.addStudent(new Student("Duck","Donald") );

// print out the collection of students (only one has a grade)

//19 Why don't three of the students have any grades?

//20 Why are they not printed out in the order that they were added?

System.out.println("printing entire class one grade added");

System.out.println(csci3381);

System.out.println();

//21 How many Micky Mouses are there after the next line?

Student testParameter = new Student ("Mouse","Micky");

//22 what is the following line of code for?

Student addTo = csci3381.getStudent(testParameter);

addTo.addGrade(100);

System.out.println("printing entire class two grades added");

System.out.println(csci3381);

System.out.println();

//23 How would this behave if I made changed the previous code to:

// Student testParamter = new Student ("Duck","Micky");

// Why is the following code the incorrect way to add a grade to a student...

testParameter = new Student ("Duck","Daffy");

testParameter.addGrade(50);

addTo = csci3381.getStudent(testParameter);

System.out.println("printing entire class ??? grades added");

System.out.println(csci3381);

System.out.println();

// this is the BEST way to add a student. first, create a temp parameter

testParameter = new Student ("Fudd","Elmer");

// try to retrieve the Student object, but it doesn't exist

addTo = csci3381.getStudent(testParameter);

//24 What does the following if do?

if (addTo == null) {

addTo = testParameter;

csci3381.addStudent(addTo);

}

//25 Now When addTo is changed, this changes the

// grade of the student in the roster. Why?

addTo.addGrade(90);

System.out.println("printing entire class 3 grades added");

System.out.println(csci3381);

System.out.println();

}

}