Question

***Given a class called Student and a class called Course that contains an ArrayList of Student. Write a method called dropStudent() as described below. Refer to Student.java below to learn what methods are available.***

Course.java

import java.util.*;
import java.io.*;
/******************************************************
* A list of students in a course
*****************************************************/
public class Course{

/** collection of Students */
private ArrayList<Student> roster;

/*****************************************************
Constructor for objects of class Course
*****************************************************/
public Course(){
roster = new ArrayList<Student>();
}

/*****************************************************
Remove student with the provided last name. Do
nothing if last name not found.
*****************************************************/
public void dropStudent(String last){
/** Your code goes here */
  
}
  
/*****************************************************
Add a student to the course
*****************************************************/
public void addStudent(Student s){
roster.add(s);
}
  
public int countStudents(){
return roster.size();
}
  
/*****************************************************
Main method for testing
*****************************************************/
public static void main(String args[]){
Course cis162 = new Course();
cis162.addStudent(new Student("Henry", "Cabot", 3.5));
cis162.addStudent(new Student("Brenda", "Stern", 2.0));
cis162.addStudent(new Student("Lynda", "Robison", 3.2));
cis162.addStudent(new Student("Jane", "Flynn", 3.9));
cis162.dropStudent("Stern");
}
}

Student.java

import java.text.*;
/*************************************************
* A simple student class including name and gpa.
*
* @author Scott Grissom
* @version March 21, 2016
*************************************************/
public class Student{
  
/** student name */
private String first, last;
  
/** student GPA */
private double gpa;

/************************************************
Constructor for Student
************************************************/
public Student(String f, String l, double d){
first = f;
last = l;
gpa = d;
}
  
/************************************************
@return GPA
************************************************/
public double getGPA(){
return gpa;
}

/************************************************
@return last name
************************************************/
public String getLast(){
return last;
}
  
/************************************************
to String
@return String representation of the object
************************************************/   
public String toString(){
DecimalFormat fmt = new DecimalFormat("#.0");
return first + " " + last + " " + fmt.format(gpa);
}
  
public static void main (String [] args){
Student s = new Student ("Henry", "Walker", 3.6);
System.out.println(s);
}

}

Answer 1

import java.util.*;
import java.io.*;

/******************************************************
 * A list of students in a course
 *****************************************************/
public class Course {

    /**
     * collection of Students
     */
    private ArrayList<Student> roster;

    /*****************************************************
     Constructor for objects of class Course
     *****************************************************/
    public Course() {
        roster = new ArrayList<Student>();
    }

    /*****************************************************
     Remove student with the provided last name. Do
     nothing if last name not found.
     *****************************************************/
    public void dropStudent(String last) {
        int index = -1;
        for (int i = 0; i < roster.size(); i++) {
            if (roster.get(i).getLast().equals(last)) {
                index = i;
            }
        }
        if (index != -1) {
            roster.remove(index);
        }
    }

    /*****************************************************
     Add a student to the course
     *****************************************************/
    public void addStudent(Student s) {
        roster.add(s);
    }

    public int countStudents() {
        return roster.size();
    }

    /*****************************************************
     Main method for testing
     *****************************************************/
    public static void main(String args[]) {
        Course cis162 = new Course();
        cis162.addStudent(new Student("Henry", "Cabot", 3.5));
        cis162.addStudent(new Student("Brenda", "Stern", 2.0));
        cis162.addStudent(new Student("Lynda", "Robison", 3.2));
        cis162.addStudent(new Student("Jane", "Flynn", 3.9));
        cis162.dropStudent("Stern");
    }
}