??? /** * The Roster class encapsulates an ArrayList<Student> which stores the *

Question

???

/**
* The Roster class encapsulates an ArrayList<Student> which stores the
* information for each student in the gradebook.
*/
public class Roster {

    // Declare mStudentList
    private ArrayList<Student> mStudentList;

    /**
     * Roster()
     *
     * PSEUDOCODE: Create mStudentList.
     */
    public Roster() {
        mStudentList = new ArrayList<>();
    }

    /**
     * addStudent()
     *
     * PSEUDOCODE: Add (append) pStudent to mStudentList.
     */
    public void addStudent(Student pStudent) {
        mStudentList.add(pStudent);
    }

    /**
     * getStudent() Searches mStudentList for a Student with pLastName.
     *
     * PSEUDOCODE: index = Call Searcher.search(getStudentList(), pLastName) If
     * index == -1 Then Return null Else return the Student object in
     * mStudentList at index
     */
    public getStudent(String pLastName) {
       ???
    }

    /**
     * getStudentList() Accessor method for mStudentList.
     */
    public ArrayList<Student> getStudentList() {
        return mStudentList;
    }

    /**
     * setStudentList() Mutator method for mStudentList.
     */
    public void setStudentList(ArrayList<Student> pStudentList) {
        mStudentList = pStudentList;
    }

    /**
     * sortRoster() Called to sort the roster by last name.
     *
     * PSEUDOCODE: Call Sorter.sort() passing the list of students
     */
    ???

Explanation / Answer

main.java

import javax.swing.*;
import java.io.FileNotFoundException;

public class Main {

// The Roster of students that is read from "gradebook.txt".
private Roster mRoster;

// A reference to the View object.
private View mView;

public static void main(String[] pArgs) {
new Main().run();
}

//Exits the program when the exit button is clicked
public void exit() {
try {
GradebookWriter gradeBookWriter = new GradebookWriter("gradebook.txt");
gradeBookWriter.writeGradebook(getRoster());
System.exit(0);
} catch (FileNotFoundException pException) {
getView().messageBox("Could not open gradebook.txt for writing. Exiting without saving.");
System.exit(-1);
}
}

public Roster getRoster() {
return mRoster;
}

public void setRoster(Roster pRoster) {
mRoster = pRoster;
}

public View getView() {
return mView;
}

public void setView(View pView) {
mView = pView;
}

//run() is the main routine.
private void run() {
JFrame.setDefaultLookAndFeelDecorated(false);
setView(new View(this));
try {
GradebookReader pGradeBook = new GradebookReader("gradebook.txt");
setRoster(pGradeBook.readGradebook());
mRoster = getRoster();


} catch (FileNotFoundException pException) {
getView().messageBox("Could not open gradebook.txt for reading. Exiting.");
System.exit(-1);
}
}

//Search is called when the search button is clicked
public Student search(String pLastName) {
return getRoster().getStudent(pLastName);
}
}

GradebookReader.java

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;


public class GradebookReader {

//Instance variable
private Scanner mIn;

//Attempts to open the gradebook file for reading.
public GradebookReader(String pFname) throws FileNotFoundException {
mIn = new Scanner(new File(pFname));
}

//Reads the exam scores for a Student.
private void readExam(Student pStudent) {
for (int n = 0; n < CourseConstants.NUM_EXAMS; ++n) {
pStudent.addExam(mIn.nextInt());
}
}

//Called to read the gradebook information.
public Roster readGradebook() {
Roster roster = readRoster();
roster.sortRoster();
return roster;
}

//Reads the homework scores for a Student.
private void readHomework(Student pStudent) {
for (int n = 0; n < CourseConstants.NUM_HOMEWORKS; ++n) {
pStudent.addHomework(mIn.nextInt());
}
}

//Reads the student information from the input file adding Student objecs to the roster.
private Roster readRoster() {
Roster roster = new Roster();
while (mIn.hasNext()) {
String lastName = mIn.next();
String firstName = mIn.next();
Student student = new Student(firstName, lastName);
readHomework(student);
readExam(student);
roster.addStudent(student);
}
return roster;
}
}

GradebookWriter.java

import java.io.FileNotFoundException;
import java.io.PrintWriter;


public class GradebookWriter extends PrintWriter {

    //GradeWriter constructor
    public GradebookWriter(String pFname) throws FileNotFoundException {
        super(pFname);
    }

    //Writes the gradebook info to the file, which was opened in the ctor.
    public void writeGradebook(Roster pRoster) {

        for (Student student : pRoster.getStudentList()) {

            println(student);
        }

        close();
    }
}

gradebook.txt

Simpson Lisa 25 25 25 25 100 100
Flintstone Fred 15 17 22 18 80 60
Jetson George 20 21 22 23 70 83
Explosion Nathan 5 4 3 2 1 0
Muntz Nelson 20 15 10 5 60 70
Terwilliger Robert 23 21 19 17 80 90
Flanders Ned 12 14 17 23 85 95
Bouvier Selma 16 16 16 16 16 16
Spuckler Cletus 1 2 3 4 5 6
Wiggum Clancy 6 5 4 3 2 1
Skinner Seymour 19 23 21 24 78 83

Roster.java

import java.util.ArrayList;

public class Roster {

    // Declare mStudentList
    private ArrayList<Student> mStudentList;

    public Roster() {

        mStudentList = new ArrayList<>();
        setStudentList(mStudentList);
    }

    //Add student to the list
    public void addStudent(Student pStudent) {
        mStudentList.add(pStudent);
    }

    //Get a student by calling searcher
    public Student getStudent(String pLastName) {
        int index = Searcher.search(getStudentList(), pLastName);
        if (index == -1) {
            return null;
        } else
            return mStudentList.get(index);
    }

    public ArrayList<Student> getStudentList() {
        return mStudentList;
    }

    protected void setStudentList(ArrayList<Student> pStudentList) {
        mStudentList = pStudentList;
    }

    //Sort the roster
    public void sortRoster() {
        //Sorter.sort(mStudentList.subList(1, mStudentList.size()));
        Sorter.sort(mStudentList);
    }

    //Roster to String
    @Override
    public String toString() {
        String result = "";
        for (Student student : getStudentList()) result += student + " ";
        return result;
    }
}

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