Question

please solve this Java program. I need some explain.

2. The data file studentData.txt contains a list of student's name, major, grade points, and credit hours. The number of students is unknown. The data file is on D2L. studentData.txt Major Grade Points Credit Hours Name Jacob Michael Joshua Matthew Samantha CS Math CS Art Business 42 80 48 39 100 12 25 12 10 34 UK Write a program that reads the data from the data file, calculates the GPA (grade points/ credit hours), then saves the student information and GPA in another file (studentResult.txt). The program should also calculate and save the following data: - Average GPA of CS majors and the number of CS majors studentResult.txt Name Major Grade Points Credit Hours GPA Jacob Michael Joshua Matthew Samantha Elizabeth CS Math Cs Art Business CS 4 2 80 48 39 100 98 12 25 12 10 3 4 25 3.50 3.20 4.00 3.90 2.94 3.92 Brandon Christian Dylan Samuel cs Art Art Math 48 39 100 98 12 10 34 25 4.00 3.90 2.94 3.92 Average GPA of Cs students: 3.43 Number of CS Students: 14 - Use printf method to format the output with alignment, spacing, and decimal places. - Use java File, File Writer, PrintWriter objects for File IO. Do not use other types of /O objects. Do not use try and catch to handle exceptions 5

Answer 1

############### Student.java ###############
/**
* The Class Student.
*/
public class Student {

   /** The name. */
   private String name;

   /** The major. */
   private String major;

   /** The grade point. */
   private int gradePoint;

   /** The credit hours. */
   private int creditHours;

   /**
   * Instantiates a new student.
   *
   * @param name the name
   * @param major the major
   * @param gradePoint the grade point
   * @param creditHours the credit hours
   */
   public Student(String name, String major, int gradePoint, int creditHours) {
       super();
       this.name = name;
       this.major = major;
       this.gradePoint = gradePoint;
       this.creditHours = creditHours;
   }

   /**
   * Gets the name.
   *
   * @return the name
   */
   public String getName() {
       return name;
   }

   /**
   * Gets the major.
   *
   * @return the major
   */
   public String getMajor() {
       return major;
   }

   /**
   * Gets the grade point.
   *
   * @return the grade point
   */
   public int getGradePoint() {
       return gradePoint;
   }

   /**
   * Gets the credit hours.
   *
   * @return the credit hours
   */
   public int getCreditHours() {
       return creditHours;
   }

}

##################### GPACalculator.java #############

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;

/**
* The Class GPACalculator.
*/
public class GPACalculator {

   /** The students. */
   private List<Student> students;

   /**
   * Instantiates a new GPA calculator.
   *
   * @throws IOException Signals that an I/O exception has occurred.
   */
   public GPACalculator() throws IOException {
       this.students = new ArrayList<>();
       readFile();
       calculateGPA();
   }

   /**
   * Read file.
   *
   * @throws IOException Signals that an I/O exception has occurred.
   */
   private void readFile() throws IOException {
       System.out.println("****** File reading started *********");
       FileReader fr = new FileReader("studentdata.txt");
       BufferedReader br = new BufferedReader(fr);
       String line = br.readLine();
       while ((line = br.readLine()) != null) {
           String[] data = line.split(" ");
           String name = data[0];
           String major = data[1];
           int gradePoint = Integer.parseInt(data[2]);
           int creditHours = Integer.parseInt(data[3]);
           students.add(new Student(name, major, gradePoint, creditHours));
       }
       br.close();
       System.out.println("****** File reading finished *********");
   }

   /**
   * Calculate GPA.
   *
   * @throws FileNotFoundException the file not found exception
   */
   public void calculateGPA() throws FileNotFoundException {
       System.out.println("****** GPA calculation started *********");
       PrintWriter writer = new PrintWriter("studentresults.txt");
       double csGpa = 0.0;
       int cs = 0;
       writer.write("Name Major Grade_points Credit_hours GPA");
       writer.println();
       for (Student s : students) {
           double gpa = s.getGradePoint() / s.getCreditHours();
           if (s.getMajor().equalsIgnoreCase("cs")) {
               csGpa += gpa;
               cs++;
           }
           writer.write(String.format("%s %s %d %d %.2f", s.getName(), s.getMajor(), s.getGradePoint(), s.getCreditHours(), gpa));
           writer.println();
       }
       writer.println();
       writer.println();
       writer.write(String.format("Average GPA of CS Students: %.2f", (csGpa / cs)));
       writer.println();
       writer.write(String.format("Number of CS Students: %d", cs));
       writer.println();
       writer.flush();
       System.out.println("****** GPA calculation finished *********");
       writer.close();
   }

   /**
   * The main method.
   *
   * @param args the arguments
   * @throws IOException Signals that an I/O exception has occurred.
   */
   public static void main(String[] args) throws IOException {
       new GPACalculator();
   }
}

############# studentdata.txt ###########
Name Major Grade_point Credit_hours
Jacob CS 42 12
Michael Math 80 25
Joshua CS 48 12
Matthew Art 39 10
Samantha Business 100 34
Elizabeth CS 98 25
Brandon CS 48 12
Dylan Art 39 10
Samuel Art 100 34
Christian Math 98 25

############ studentresults.txt ############
Name Major Grade_points Credit_hours GPA
Jacob CS 42 12 3.00
Michael Math 80 25 3.00
Joshua CS 48 12 4.00
Matthew Art 39 10 3.00
Samantha Business 100 34 2.00
Elizabeth CS 98 25 3.00
Brandon CS 48 12 4.00
Dylan Art 39 10 3.00
Samuel Art 100 34 2.00
Christian Math 98 25 3.00

Average GPA of CS Students: 3.50
Number of CS Students: 4