Question

For this lab assignment, you will be writing a few classes that can be used by an educator to grade multiple choice exams. It will give you experience using some Standard Java Classes (Strings, Lists, Maps), which you will need for future projects. The following are the required classes:

1. Student – a Student object has three private instance variables: lastName, a String; firstName, a String; and average, a double. It has accessor methods for lastName and firstName, and an accessor and mutator method for average. It has two constructors: a default constructor that creates a default Student, and one that has two String parameters to initialize firstName and lastName. The initial average of all Student objects is 0.

2. UnitTest – a UnitTest object represents an exam for a class of Students. It has two instance variables: input, a Scanner object, and answers, an ArrayList of Strings that represents the correct answers on the exam. In the constructor, you must read from the file “answers.txt” which represents the correct answers for this exam. You must write one method in this class: calculateGrade, which has an ArrayList of Strings as a parameter. This ArrayList has all of the Students answers for their exam. To grade the exam, you compare the answers and, if they are equal, count it as correct. The method returns a percentage, as a double in the range [0.0...100.0].

3. UnitTestRunner – A UnitTestRunner is the runner for the lab. There is a lot of leeway as to how you can define this class. It needs to do the following:

1. • Create a UnitTest object.
   • Read in the Student information from the file allExams.txt. The file is of the format last name, first name, and answers for their exam (always ten letters).
   • Create Student objects by using the last name and first name String objects read from the file.
   • Add the Student objects to an ArrayList of Students.
   • Add all answers to an ArrayList of Strings.
   • Add these answers to a HashMap. The HashMap is of type >. The String key must be the concatenation of a Student’s last name followed by their first name, with no spaces and in lower case. Hence, the String for John Smith would be smithjohn. The value to put into the HashMap is their ArrayList answers.
   • Grade all of the exams. Go through the ArrayList of Student objects to get the answers from the HashMap, and use the calculateGrade method from the UnitTest object you created to grade the Student’s exam. Use the mutator method for average in the Student object to save the grade as the average.
   • Finally, print all of the Students’ names, in the form first name and last name, separated by a space, and their grade after.
2. Can the UnitTest object be modified easily? As it is, it only initializes an answer key and calculates the percentage correct. Are there any other functions that you think a UnitTest may hold responsibility? Think about if you were writing a more robust program for actual teachers – what other functions may prove useful to them? Add this response to your output file.

AllExam.txt

Tobacco Christian A B C D D C B A A B
Russo James D A C B A C A D A A 
Smith John A A A A A A A A A A
Henderson James B B B B B B B B B B
Russo Michael C C C C C C C C C C
DeMartino John A B C D D C B A C D
Scafuri Frank A B C D A C B A A D

Answer.txt

A B C D D C B A A B

Answer 1

Student.java

public class Student {
   String lastName;
   String firstName;
   double average;
   public String getLastName() {
       return lastName;
   }
   public void setLastName(String lastName) {
       this.lastName = lastName;
   }
   public String getFirstName() {
       return firstName;
   }
   public void setFirstName(String firstName) {
       this.firstName = firstName;
   }
   public double getAverage() {
       return average;
   }
   public void setAverage(double average) {
       this.average = average;
   }
  
   public Student() {
      
   }
  
   public Student(String lastName, String firstName) {
       this.lastName=lastName;
       this.firstName=firstName;
       this.average=0;
   }

}

UnitTest.java

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Scanner;

public class UnitTest {
  
   Scanner input;
   ArrayList<String> answers;
  
   public UnitTest() {
      
       answers = new ArrayList<>();
      
       String[] fields;
       FileInputStream filestream;
       String path = "Answers.txt";
         
       try {
               filestream = new FileInputStream(path);
               BufferedReader br = new BufferedReader(new InputStreamReader(filestream));

               String str = br.readLine();
  
fields = str.split(" ");

for(int i=0;i<10;i++)
   answers.add(fields[i]);
              
               br.close();

           } catch (FileNotFoundException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
           } catch (IOException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
           }
         
      
      
      
   }
  
   public double calculateGrade(ArrayList<String> answer) {
      
       int count=0;
       for(int i=0;i<answers.size();i++) {
           if(answers.get(i).compareTo(answer.get(i))==0)
               ++count;
       }
      
       return count*100/answer.size();
      
   }

}

UnitTestRunner.java

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;

public class UnitTestRunnner {

   public static void main(String[] args) {
       // TODO Auto-generated method stub

       UnitTest unit = new UnitTest();
      
       String name ;
      
       ArrayList<String> grades;
      
       ArrayList<Student> students = new ArrayList<>();
      
       HashMap<String,ArrayList<String>> map = new HashMap<>();
      
       String[] fields;
      
      
       FileInputStream filestream;
       String path = "AllExams.txt";
         
       try {
               filestream = new FileInputStream(path);
               BufferedReader br = new BufferedReader(new InputStreamReader(filestream));

               String str = br.readLine();

  
               while (str != null) {
                  
                   name = new String();
                   grades=new ArrayList<String>();
                  
                   fields = str.split(" ");
                  
                   name= fields[1]+fields[0];
                  
                   students.add(new Student(fields[0],fields[1]));
                  
                   for(int i=0;i<10;i++) {
                       grades.add(fields[i+2]);
                   }
                  
                   map.put(name, grades);
                  
                   str = br.readLine();  
               }

               br.close();

           } catch (FileNotFoundException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
           } catch (IOException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
           }
         
       ArrayList<ArrayList<String>> values = new ArrayList<>(map.values());
         
       for(int i=0; i<students.size();i++) {
             
           System.out.println(students.get(i).getFirstName()+" " + students.get(i).getLastName()+ " " + unit.calculateGrade(values.get(i)));
       }
         
      
   }

}

Output

Christian Tobacco 30.0
James Russo 30.0
John Smith 80.0
James Henderson 20.0
Michael Russo 100.0
John DeMartino 80.0
Frank Scafuri 30.0

Screenshot

Student.java UnitTest.java UnitTestRunnner.java X while (str != null) { name = new String(); grades=new ArrayList<String>(); fields = str.split(" "); name= fields[1]+fields [0]; students.add(new Student(fields [0], fields[1])); for(int i=0; i<10; i++) { grades.add(fields[i+2]); map.put(name, grades); str = br.readLine(); - X : 9 * - - - Problems @ Javadoc Declaration & Console X <terminated > UnitTestRunnner [Java Application] C:\Program FilesVava\jre 1.8.0_152\bin\javaw.exe (Sep 20, 2019, 10:06:44 AM) Christian Tobacco 30.0 James Russo 30.0 John Smith 80.0 James Henderson 20.0 Michael Russo 100.0 John DeMartino 80.0 Frank Scafuri 30.0 Writable Smart Insert 73: 141

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