Q1:Write a public Java class called Student that represents one student. The cla

Question

Q1:Write a public Java class called Student that represents one student. The class should include:

- Instance variables ID (int), firstName (String), and GPA (double).

- A constructor with no parameters that sets the instance variables, respectively, to these values: -111 (not set) -2.22

- A constructor with three parameters that sets the instance variables to the parameter values.

- Getter methods for each instance variable.

- Setter methods for each instance variable.

- equals and toString methods.

Q2: Write a Java console application that uses the Student class created in Question 1 to create three student objects:

- s1 is created with the no-parameter constructor.

- s2 is created with the no-parameter constructor but the user is prompted for the student data.

        - s3 is created with the three-parameter constructor. Use these values:

                  78

                  Mary

                  3.25

Use the Java project created in Question 1 and simply add a class to it called StudentDemo. Print the information stored in each student object. Compare and print whether student objects s2 and s3 are equal.

Explanation / Answer

import java.util.Scanner;

class Student {
   private int ID;
   private String firstName;
   private double GPA;
  

//default constructor
   public Student() {
       this.id=-111;
       this.gpa=-2.22;
       this.firstName="Not set";
   }
  
//paramaterized constructor
   public Student(int ID,String firstName,double GPA) {
       this.GPA=GPA;
       this.ID=ID;
       this.firstName=firstName;
   }
   public int getID() {
       return ID;
   }
   public void setID(int iD) {
       ID = iD;
   }
   public String getFirstName() {
       return firstName;
   }
   public void setFirstName(String firstName) {
       this.firstName = firstName;
   }
   public double getGPA() {
       return GPA;
   }
   public void setGPA(double gPA) {
       GPA = gPA;
   }
  

//overrides the equals method and returns the student info
   @Override
   public String toString() {
       return this.firstName+" having ID "+this.ID+" has scored "+this.GPA+" GPA";
   }
  

//overrides the equals method to check the two students are equal if they have same name,id and gpa
   @Override
   public boolean equals(Object obj) {
       if (obj == this) {
                return true;
            }
       if (!(obj instanceof Student)) {
                return false;
            }
       Student student=(Student)obj;
       return this.ID==student.getID()&&this.firstName.equals(student.getFirstName())&&Double.compare(this.GPA, student.getGPA())==0;
   }
}

public class StudentDemo {

   public static void main(String[] args) {
       Student s1=new Student();
       Student s2=new Student();
       System.out.println("Please enter first name : ");
       Scanner sc=new Scanner(System.in);
       String enteredfirstName=sc.next();
       System.out.println("Please enter Id : ");
       int enteredId=sc.nextInt();
       System.out.println("Please enter GPA : ");
       double enteredGPA=sc.nextDouble();
       s2.setFirstName(enteredfirstName);
       s2.setID(enteredId);
       s2.setGPA(enteredGPA);
       sc.close();
       Student s3=new Student(78, "MARY", 3.25);
       System.out.println(s1);
       System.out.println(s2);
       System.out.println(s3);
       if(s2.equals(s3)){
           System.out.println("s2 and s3 are equal");
       }else{
           System.out.println("s2 and s3 are not equal");
       }
      
   }

}

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