Question

Instructions:DevelopaprogramnamedMakeStudentsthat

•  Reads student data from Readme.txt and creates student instances

  o usetheStudentclassprovidedforthelab

•  Saves student instances in an array list

•  Displays the size of the list

•  Iterates through the list displaying students one student per line, as in:

  for (Student s: myList) { System.out.println(s);

  }

  new File("Readme.txt")).useDelimiter(",");

  Then to get each token we can use f.next() or f.nextBoolean()
  Note that student gender is of type char, and that char value can be obtained using

  f.next().charAt(0)

  YoumustusetheStudentclassgivenalongwiththislab. ThisversionofStudentissimpler than the one in the text – this version makes no reference to the Subject class (not needed for this lab).

  Your BlueJ project will include

  Readme.txt, Student.java, and MakeStudents.java

  SubmitMakeStudents.javatotheemailcorrespondingtoyourlabsectionwithsubject Lab 10

Copy the student data provided for this lab to Readme.txt. The data comprises comma-

separated values for fields: first name, last name, gender and active.

Previously we have used the Scanner class with its default delimiter of whitespace. In this

lab, use the Scanner class with comma as the delimiter:

Scanner f = new Scanner

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

public class Student {

// class fields

private static int lastId;

// instance fields

private int id;

private String firstName;

private String lastName;

private char gender;

private boolean active;

// first constructor, no arguments

public Student(){

id = nextId();

// default values for a student:

firstName = "unknown";

lastName = "unknown";

gender = '?';

active = false;

}

// second constructor, four arguments

public Student (String firstName, String lastName, char gender, boolean active){

id = nextId();

//

// when parameters and fields have the same

// name they are distinquished this way:

// a field name alone refers to the parameter

// a field name prefixed with "this."

// refers to an object's fields.

this.firstName = firstName;

this.lastName = lastName;

this.gender = gender;

this.active = active;

}

private int nextId(){

// increment lastId and return the new value

// to be used for the new student.

return ++lastId;

}

public int getId(){

return id;

}

public static int getLastId(){

return lastId;

}

public String getFirstName(){

return firstName;

}

public String getLastName(){

return lastName;

}

public char getGender(){

return gender;

}

public boolean isActive(){

return active;

}

public void setLastId(int newLastId){

lastId = newLastId;

}

// no setter for the student's id field

// public void setId(int newId){

// id = newId;

// }

public void setFirstName(String newFirstName){

firstName = newFirstName;

}

public void setLastName(String newLastName){

lastName = newLastName;

}

public void setGender(char newGender){

gender = newGender;

}

public void setActive(boolean newActive){

active = newActive;

}

public String toString(){

return id+" "+firstName+" "+lastName;

}

public boolean equals(Student s){

return id == s.id;

}

}

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

Readme.txt

Harry,Potter,m,true,Albus,Dumbledore,m,true,Serverus,Snape,m,true,Rubeus,Sirius,m,true,Hermione,Granger,f,true,Ron,Weasley,m,true,Draco,Malfoy,m,true,Luna,Lovegood,f,true,Regulus,Black,m,true,Neville,Longbottom,m,true,Nymphadora,Tonks,f,true,Remus,Lupin,m,true,Fleur,Delacour,f,true,Dolores,Umbridge,f,true,Gellert,Grindelwald,m,true

Answer 1

A) Program for the above question is given below. Name the file name as MakeStudents.java. The other files Student.java and Readme.txt should be in the same folder.

Explanation:
The student data is read form Readme.txt using Scanner class as specified with comma as the delimiter and student instances are created using the Student class provided. The Student instances are stored in an ArrayList as specified. Later the size of the list is printed and the ArrayList is iterated and the students one per line are also printed.

Code:

import java.util.*;
import java.io.File;
import java.io.IOException;

public class MakeStudents {
   public static void main(String[] args)
{
   ArrayList<Student> studentList = new ArrayList<Student>();
   try {

       Scanner sc = new Scanner(new File("Readme.txt")).useDelimiter(",");
       while (sc.hasNext()) {
           String firstName = sc.next();
               String lastName = sc.next();
               char gender = sc.next().charAt(0);
               boolean active = sc.nextBoolean();

               Student student = new Student(firstName, lastName, gender, active);
               studentList.add(student);
       }
       sc.close();
   } catch (IOException e) {
       e.printStackTrace();
   }
   System.out.println("Size of the list: " + studentList.size());
   for (Student s: studentList) {
       System.out.println(s);
   }
}
}

Please refer to the screenshot of the code to understand the indentation of the code

Output: The output is given for the Readme.txt file provided.

import java.util.*; import java.io.File; import java.io.IOException; public class MakeStudents { public static void main(String[] args) ArrayList<Student> studentList = new ArrayList<Student>(); try {l Scanner sc = new Scanner(new File("Readme.txt")).useDelimiter(","); while (sc.hasNext()) { String firstName = sc.next(); String lastName = sc.next(); char gender = sc.next().charAt(@); boolean active = sc.nextBoolean(); Student student = new Student(firstName, lastName, gender, active); studentList.add(student); sc.close(); '} catch (IOException e) { e.printStackTrace(); System.out.println("Size of the list: " + studentList.size()); for (Student s: studentList) { System.out.println(s);

Size of the list: 7 1 Harry Potter 2 Albus Dumbledore 3 Serverus Snape 4 Rubeus Sirius 5 Hermione Granger 6 Ron Weasley 7 Draco Malfoy