In this assignment, you will be making a program that reads from a file called classes.txt and displaying that information to the user. The goal for this assignment is to learn how to handle potential exceptions. Use the given template to implement exception-handling techniques.

Please note: You do not have to edit any parts of the code. Only handle exceptions where the code says /* INSERT CODE HERE */

The four exceptions you have to handle are:

NumberFormatException FileNotFoundException ArrayIndexOutOfBoundsException NoSuchFieldException 

classes.txt:

14 CSCE155;3;3:00PM;;Computer Science I CSCE156;4;12:00PM;CSCE155;Computer Science II CSCE230;4;8:30AM;CSCE155;Computer Organization CSCE235;3;9:30AM;CSCE155;Introduction to Discrete Structures CSCE251;1;;CSCE155;Unix Programming Environment CSCE310;3;11:30AM;CSCE156;Data Structures and Algorithms CSCE322;3;4:30PM;CSCE156,CSCE230,CSCE311;Programming Language Concepts CSCE351;3;1:30PM;CSCE230,CSCE310,CSCE311 CSCE???;?;;; CSCE361;3;9:00AM;CSCE310,CSCE311;Software Engineering CSCE423;3;2:00PM;CSCE235,CSCE310,CSCE310;Design and Analysis of Algorithms CSCE428;3;4:30PM;CSCE235,CSCE310,CSCE311;Automata, Computation, and Formal Languages CSCE486;3;1:00PM;CSCE361;Computer Science Professional Development CSCE487;3;10:00AM;CSCE486;Computer Science Senior Design Project 

import java.util.*;

import java.io.*;

import java.lang.*;

public class Main

{

public static void main(String[] args)

{

Scanner classesInput = null; // Reads course information from classes.txt

Scanner keyboard = new Scanner(System.in); // Reads input from user

/* INSERT CODE HERE */

try{

// Attempts to create scanner to read from classes.txt

classesInput = new Scanner(new File("classes.txt"));

}

catch(FileNotFoundException e){

}

String line; // Variable used to store each individual line

String[] parts; // Variable used to store the parts of each line (after splitting it)

// The first line of the text file has the number of courses

int numClasses = Integer.parseInt(classesInput.nextLine());

// Arrays to store information about each class

String[] courseNumbers = new String[numClasses];

int[] creditHours = new int[numClasses];

String[] times = new String[numClasses];

String[] prerequisites = new String[numClasses];

String[] courseNames = new String[numClasses];

// Read through all of the classes

for (int index = 0; index < numClasses; index++)

{

// Read one course at a time

line = classesInput.nextLine();

// The course information is split by semi-colons

parts = line.split(";");

// The course will always have a course number

courseNumbers[index] = parts[0];

try{

/* INSERT CODE HERE */

// Try to parse the credit hour amount

creditHours[index] = Integer.parseInt(parts[1]);

}

catch(NumberFormatException e) {

}

try{

times[index] = parts[2];

try{

if (times[index].equals(""))

{

// The times component is empty

throw new NoSuchFieldException();

}

}

catch(NoSuchFieldException e) {

}

/* INSERT CODE HERE */

prerequisites[index] = parts[3];

try{

if (prerequisites[index].equals(""))

{

// The prerequisites component is empty

throw new NoSuchFieldException();

}

}

catch(NoSuchFieldException e) {

}

/* INSERT CODE HERE */

courseNames[index] = parts[4];

}

catch(ArrayIndexOutOfBoundsException e){

}

}

/*Menu:

* P - Print out courses

* B - print all course names

* C - print all course numbers

* Q - Quit

*/

// Initialize 'input' to a known invalid value

char input = '?';

do

{

// Prompt the user

System.out.println("Choose an option: ");

// Read in the input, convert it to uppercase letters, then store ONLY the first letter

input = (keyboard.nextLine()).toUpperCase().charAt(0);

if (input == 'P')

// Print out all course information

printCourses(courseNumbers, creditHours, times, prerequisites, courseNames);

else if (input == 'B')

// Print out all course names

printCourseNames(courseNames);

else if (input == 'C')

// Print out all course numbers

printCourseNumbers(courseNumbers);

else if (input == 'Q')

{

// Quit the program --> It will quit on the while condition check

}

else

{

// User has input an invalid option

System.out.println("Invalid Option");

}

}

while(input != 'Q');

}

public static void printCourseNames(String[] names)

{

System.out.println("COURSE NAMES:");

for (int i = 0; i < names.length; i++)

{

// Print out the individual course name, one per line

System.out.println(names[i]);

}

System.out.println(); // Print empty line after course names

}

/*****************************************************************

* printCourseNumbers(...) takes in an array of course numbers and

* prints each course number on an individual line

*

* @param nums An array of course numbers that were read in

* from classes.txt --> Corresponds to courseNumbers from main(...)

*

* @return void Does not return any values

******************************************************************/

public static void printCourseNumbers(String[] nums)

{

System.out.println("COURSE NUMBERS:");

for (int i = 0; i < nums.length; i++)

{

// Print out the individual course numbers, one per line

System.out.println(nums[i]);

}

System.out.println(); // Print empty line after course numbers

}

/*****************************************************************

* printCourses(...) takes in all information for all courses and

* prints out each course's course number, coures name, credit

* hours, meeting time, and prerequisites

*

* @param num An array of course numbers that were read in

* from classes.txt --> Corresponds to courseNumbers from main(...)

*

* @param hours An array of course credit hours for each course

* that were read in from classes.txt --> Corresponds to

* creditHours from main(...)

*

* @param times An array of meeting times for each course that

* were read in from classes.txt --> Corresponds to times from

* main(...)

*

* @param pre An array of prerequisites for each course, with

* the format of prereq1,prereq2,prereq3,... that was read in from

* classes.txt --> Corresponds to prerequisities from main(...)

*

* @param names An array of course names that were read in from

* classes.txt --> Corresponds to courseNames from main(...)

*

* @return void Does not return any values

******************************************************************/

public static void printCourses(String[] num, int[] hours,String[] times, String[] pre, String[] names)

{

String hoursMessage;

String prereqMessage;

for (int i = 0; i < num.length; i++)

{

// Determine if the credit hours amount is valid

if (hours[i] == -1)

{

// Credit hours amount is invalid

hoursMessage = num[i] + " does not have any credit hours";

}

else

{

// Credit hours amount is valid

hoursMessage = Integer.toString(hours[i]);

}

// Format the prerequisites

String[] parts = pre[i].split(",");

StringBuilder prerequisitesBuilder = new StringBuilder();

String prerequisiteMessage = "";

for (int p = 0; p < parts.length; p++)

{

// Determine th number of prerequisites for each course

if (parts.length > 1)

{

// If there is more than one prerequisite

if (p < parts.length - 1)

{

// If it's not the last prerequisite

prerequisitesBuilder.append(parts[p]); // Add the prerequisite to the string

prerequisitesBuilder.append(", "); // Add a comma to separate the courses

}

else

{

// If it is the last prerequisite

prerequisitesBuilder.append("and ");

prerequisitesBuilder.append(parts[p]); // Add the last prerequisite

}

}

else

{

// If it is the only prerequisite

prerequisitesBuilder.append(parts[p]);

}

System.out.println("Does not have any requisite");

}

// Store the prerequisite information to print later

prerequisiteMessage = prerequisitesBuilder.toString();

// Print the course information

System.out.println("Course Number: " + num[i]);

System.out.println("Name: " + names[i]);

System.out.println("Credit Hours: " + hoursMessage);

System.out.println("Time: " + times[i]);

System.out.println("Prereqs : " + prerequisiteMessage);

System.out.println(); // Print empty line after each course

}

}

}