Question

Input

hello, I need help completing my assignment for java,Use the following test data for input and fill in missing code, and please screenshot output.

1, John Adam, 3, 93, 91, 100, Letter

2, Raymond Woo, 3, 65, 68, 63, Letter

3, Rick Smith, 3, 50, 58, 53, Letter

4, Ray Bartlett, 3, 62, 64, 69, Letter

5, Mary Russell, 3, 93, 90, 98, Letter

6, Andy Wong, 3, 89,88,84, Letter

7, Jay Russell, 3, 71,73,78, Letter

8, Jimmie Wong, 3, 70,77,72, Letter

9, Jackie Chan, 3, 85,89,84, Letter

10, Susan Wu, 3, 80,88,84, Letter

11, Bruce Lee, 4, 74, 79, 72, 75, Credit

12, Chuck Norris, 5, 63, 64, 62, 60, 68, Credit

13, Jet Li, 3, 85, 83, 89, Credit

14, Jessica Lauser, 3, 82, 84, 87, Letter

15, Mahnoosh Nik-Ahd, 2, 98, 99, Letter

Output

1 John Adam (A)

5 Mary Russell (A)

15 Mahnoosh Nik-Ahd (A)

6 Andy Wong (B)

9 Jackie Chan (B)

10 Susan Wu (B)

14 Jessica Lauser (B)

7 Jay Russell (C)

8 Jimmie Wong (C)

2 Raymond Woo (D)

4 Ray Bartlett (D)

3 Rick Smith (F)

11 Bruce Lee (CR)

13 Jet Li (CR)

12 Chuck Norris (NCR)

Submit

Copy the following in a file and submit that file:

Final output dialog box containing the complete output in a single dialog box

The source code from all the source java file.

Note that the method findGrade in class StudentExt over-rides the parent method findGrade in the parent class Student. Notice also that this method calls the parent method findGrade for determining the student’s letter grade. On return from the parent method, it changes the grade to “CR” or “NCR” in the case when a student's grade type is "Credit" as described below.

When a student's gradeType is “Credit” and the parent findGrade method returns a letter grade of "A", "B", or "C", the grade is changed to “CR”. Otherwise (for a letter grade of “D” or “F”), it is changed to “NCR”.

//class Student

//File Student.java

public class Student

{

private int id;

private String name;

private double [] scores;

public Student(int id, String n, int [] s)

{

    //Below id refers to local variable.

] this.id = id;

    name = n;

    //create scores array of same length as s array

   scores = new double [s.length];

    System.arraycopy(s, 0, scores, 0, s.length);

}

public String findGrade()

{

     //write missing code below

    String grade="";

    double sum=0;

    for (int i=0;i<scores.length;i++)

    {

         sum=sum+scores[i];

    }

    double average=sum/scores.length;

    if (average>=90.0)

         grade="A";

    else if (average>=80.0)

         grade="B";

else if (average>=70.0)
       grade="C";
       else if (average>=60.0)
       grade="D";
       else
       grade="F";
       return grade;
       }
      
       public int getId ( ){
       return id;
       }
      
       public String getName ( ){
       return name;
       }

}

//class StudentExt

//File StudentExt.java

//write the missing code

public class StudentExt

{

private String gradeType;

public StudentExt(int id, String n, int [] s, String gType)

{

    //Call the constructor to initialize 'id, name and scores

    super(id,n,s);

    //initialize gradeType here

    gradeType=gType;

}

   public String getGradeType ( )

{

     return gradeType;

}

//This method over-rides the same method in the parent class

public String findGrade ( )

{

    //call the parent method findGrade for determine letter grade

    String grade = super.findGrade ( );

    //if the gradeType is Credit, change the grade

    if (gradeType.equalsIgnoreCase ("Credit"))

    {

      if ( (grade.equalsIgnoreCase ("A")) ||

            (grade.equalsIgnoreCase ("B")) ||

            (grade.equalsIgnoreCase ("C")))

            grade = "CR";

      else

            grade = "NCR";

    }

    return grade;

}

}

//class TestStudentExt

//file: TestStudentExt.java

//Changes from TestStudent to TestStudentExt are in bol

import javax.swing.*;

import java.util.*;

public class TestStudentExt

{

public static void main(String[] args)

{

    String in;

    int nStudents, nExams;

   

    in = JOptionPane.showInputDialog("Enter number of students");

    nStudents = Integer.parseInt(in);

    // Create an array of StudentExt references

    StudentExt [] st = new StudentExt [nStudents];

    // Create StudentExt objects using loop

    for (int i = 0;i < st.length;i++)

    {

      in = JOptionPane.showInputDialog

             ("Enter one student data with items separated by comma");

      // Tokenize student data using StringTokenizer

      String delim = ",";

      String token;

StringTokenizer st = new StringTokenizer (in, delim);

      token = st.nextToken ().trim();

      int id=Integer.parseInt(token);

      String name = st.nextToken ().trim();

      token = st.nextToken ().trim();

      nExams=Integer.parseInt(token);

double[] scores;=new double[nExams];

for (int j=0;j<nExams;j++)

     {

         token = st.nextToken().trim();

         scores[j]=Double.parseDouble(token);

     }

      String gradeType= st.nextToken().trim();

      st [i] = new StudentExt (id, name, scores, gradeType);

    }

    //Create an empty output String for each type of grade

    String outA="", outB="", outC="", outD="", outF="", outCr="", outNcr="";

    //find student grades and accumulate output for each type of student.

    String grade="";

    for (int i = 0; i < st.length; i++)

    {

grade = st1[i].findGrade();
   if (grade.equalsIgnoreCase("A")) {
   //accumulate output in outA for A students.
   outA=outA+ st1[i].getId()+" "+st1[i].getName()+" ("+grade+")\n";
   }
   else if (grade.equalsIgnoreCase("B")){
   //accumulate output in outB for B students.
   outB=outB+ st1[i].getId()+" "+st1[i].getName()+" ("+grade+")\n";
   }

   else if (grade.equalsIgnoreCase("C")){
   //accumulate output in outC for C students.
   outC=outC+ st1[i].getId()+" "+st1[i].getName()+" ("+grade+")\n";
   }
  
   else if (grade.equalsIgnoreCase("D")){
   //accumulate output in outD for D students.
   outD=outD+ st1[i].getId()+" "+st1[i].getName()+" ("+grade+")\n";
   }
   else if (grade.equalsIgnoreCase("F")){
   //accumulate output in outD for D students.
   outF=outF+ st1[i].getId()+" "+st1[i].getName()+" ("+grade+")\n";
   }
   else if (grade.equalsIgnoreCase("CR")){

   //accumulate output in outCr for CR students.

       outCr=outCr+ st1[i].getId()+" "+st1[i].getName()+" ("+grade+")\n";  

}

   else if (grade.equalsIgnoreCase("NCR")){
       outNcr=outNcr+ st1[i].getId()+" "+st1[i].getName()+" ("+grade+")\n";
}

}

    String outAll=outA+outB+outC+outD+outF+ outCr+outNcr;

    // display output

    JOptionPane.showMessageDialog(null, outAll);

}

Answer 1

Please find the codes below.Most of changes in student and studentExt java..There were few typo mistake in TestStudentExt.java as well

Student.java

public class Student {
private int id;
private String name;
private double[] scores;
public Student(int id, String n, double[] s)
{
this.id = id;
name = n;
// create scores array of same length as s array
scores = new double[s.length];
System.arraycopy(s, 0, scores, 0, s.length);
}
public String findGrade()
{
// write missing code below
String grade = "";
double sum = 0;
for (int i = 0; i < scores.length; i++)
{
sum = sum + scores[i];
}
double average = sum / scores.length;
if (average >= 90.0)
grade = "A";
else if (average >= 80.0)
grade = "B";
else if (average >= 70.0)
grade = "C";
else if (average >= 60.0)
grade = "D";
else
grade = "F";
return grade;
}
public int getId() {
return id;
}
public String getName() {
return name;
}
}

-------------------------------------------------------------------------

StudentExt.java

public class StudentExt extends Student {
private String gradeType;

public StudentExt(int id, String n, double[] s, String gType) {
// Call the constructor to initialize 'id, name and scores
super(id, n, s);
// initialize gradeType here
gradeType = gType;
}

public String getGradeType() {
return gradeType;
}

// This method over-rides the same method in the parent class
public String findGrade() {
// call the parent method findGrade for determine letter grade
String grade = super.findGrade();
// if the gradeType is Credit, change the grade
if (gradeType.equalsIgnoreCase("Credit")) {
if ((grade.equalsIgnoreCase("A")) || (grade.equalsIgnoreCase("B")) || (grade.equalsIgnoreCase("C")))
grade = "CR";
else
grade = "NCR";
}
return grade;
}
}

--------------------------------------------------

TestStudentExt.java

import javax.swing.*;
import java.util.*;
public class TestStudentExt
{
public static void main(String[] args)
{
String in;
int nStudents, nExams;
in = JOptionPane.showInputDialog("Enter number of students");
nStudents = Integer.parseInt(in);
// Create an array of StudentExt references
StudentExt[] st1 = new StudentExt[nStudents];
// Create StudentExt objects using loop
for (int i = 0; i < st1.length; i++)
{
in = JOptionPane.showInputDialog
("Enter one student data with items separated by comma");
// Tokenize student data using StringTokenizer
String delim = ",";
String token;
StringTokenizer st = new StringTokenizer(in, delim);
token = st.nextToken().trim();
int id = Integer.parseInt(token);
String name = st.nextToken().trim();
token = st.nextToken().trim();
nExams = Integer.parseInt(token);
double[] scores = new double[nExams];
for (int j = 0; j < nExams; j++)
{
token = st.nextToken().trim();
scores[j] =(double) Double.parseDouble(token);
}
String gradeType = st.nextToken().trim();
st1[i] = new StudentExt(id, name, scores, gradeType);
}
for(Student s:st1)
System.out.println(s.getId());
// Create an empty output String for each type of grade
String outA = "", outB = "", outC = "", outD = "", outF = "", outCr = "", outNcr = "";
// find student grades and accumulate output for each type of student.
String grade = "";
for (int i = 0; i < st1.length; i++)
{
grade = st1[i].findGrade();
if (grade.equalsIgnoreCase("A")) {
// accumulate output in outA for A students.
outA = outA + st1[i].getId() + " " + st1[i].getName() + " (" + grade + ")\n";
} else if (grade.equalsIgnoreCase("B")) {
// accumulate output in outB for B students.
outB = outB + st1[i].getId() + " " + st1[i].getName() + " (" + grade + ")\n";
}
else if (grade.equalsIgnoreCase("C")) {
// accumulate output in outC for C students.
outC = outC + st1[i].getId() + " " + st1[i].getName() + " (" + grade + ")\n";
}
else if (grade.equalsIgnoreCase("D")) {
// accumulate output in outD for D students.
outD = outD + st1[i].getId() + " " + st1[i].getName() + " (" + grade + ")\n";
} else if (grade.equalsIgnoreCase("F")) {
// accumulate output in outD for D students.
outF = outF + st1[i].getId() + " " + st1[i].getName() + " (" + grade + ")\n";
} else if (grade.equalsIgnoreCase("CR")) {
// accumulate output in outCr for CR students.
outCr = outCr + st1[i].getId() + " " + st1[i].getName() + " (" + grade + ")\n";
}
else if (grade.equalsIgnoreCase("NCR")) {
outNcr = outNcr + st1[i].getId() + " " + st1[i].getName() + " (" + grade + ")\n";
}
}
String outAll = outA + outB + outC + outD + outF + outCr + outNcr;
// display output
JOptionPane.showMessageDialog(null, outAll);
}
}

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