Student

package com.company;

import java.util.Objects;

public class Student extends Learner{

    private int course;

    public Student(String surname, String eduInstitution, double meanMark, int course) {
        super(surname, eduInstitution, meanMark);
        this.course = course;
    }

    public int getCourse() {
        return course;
    }

    public void setCourse(int course) {
        this.course = course;
    }

    @Override
    public String toString() {
        StringBuffer stringBuffer= new StringBuffer(surname);
        stringBuffer.append(" ");
        stringBuffer.append(eduInstitution);
        stringBuffer.append(" ");
        stringBuffer.append(meanMark);
        stringBuffer.append(" ");
        stringBuffer.append(course);
        return stringBuffer.toString();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof Student)) return false;
        if (!super.equals(o)) return false;
        Student student = (Student) o;
        return getCourse() == student.getCourse();
    }

    @Override
    public int hashCode() {
        return Objects.hash(super.hashCode(), getCourse());
    }
}