Need help with program

[ahernandez980]

My group and I are fairly new to Java. We are creating a transcript system in which a user is able to retrieve their transcript based on a studentID.

Here are the classes:

/**
 * Final Group Project
 */
package finalproject;

/**
 * A class that retrieves a letter grade for a course.
 * 
 * @author Scott Renaud
 * @version 1.1
 */
public class Grade 
{
	/** A grade of A */
	private final static int A = 1;
	
	/** A grade of B */
	private final static int B = 2;
	
	/** A grade of C */
	private final static int C = 3;
	
	/** A grade of D */
	private final static int D = 4;
	
	/** A grade of F */
	private final static int F = 5;
	
	/** The numerical grade */
	private double gpa;
	
	/** The letter grade */
	private String grade;
	
	/**
	 * Constructs a new Grade object.
	 * 
	 * @param numGrade The numerical grade associated with a course.
	 */
	public Grade(String grade) 
	{
		this.grade = grade;
		checkCourseCompletion();
	}
	
	/**
	 * Returns the letter grade for a course.
	 * 
	 * @return A String literal specifying the letter grade.
	 */
	public double getGPA()
	{
		return this.gpa;
	}
	
	/**
	 * Checks if course has a grade associated with it.
	 */
	public void checkCourseCompletion()
	{
		if(!(this.grade == null));
			findGPA();
	}
	
	/**
	 * Finds the GPA based on the letter grade.
	 */
	public void findGPA()
	{
		int key = 0;
		
		if(this.grade.equals("A"))
			key = A;
		else if(this.grade.equals("B"))
			key = B;
		else if(this.grade.equals("C"))
			key = C;
		else if(this.grade.equals("D"))
			key = D;
		else if(this.grade.equals("F"))
			key = F;
		
		switch(key)
		{
		case A:
			this.gpa = 4.0;
		case B:
			this.gpa = 3.0;
		case C:
			this.gpa = 2.0;
		case D:
			this.gpa = 1.0;
		case F:
			this.gpa = 0.0;
		}
	}
	
	/**
	 * Returns the GPA associated with a course.
	 */
	public String toString()
	{
		return "Course GPA: " + gpa;
	}
	
	/**
	 * Compares two letter grades.
	 * If not the same, returns false; else true.
	 * 
	 * @param obj An Object being compared to Grade.
	 * @return A boolean response of either true or false.
	 */
	public boolean equals(Object obj)
	{
		if (!(obj instanceof Grade))
			return false;
		Grade otherGrade = (Grade) obj;
		return gpa == otherGrade.gpa;
	}
}

/**
 * Final Group Project
 */
package finalproject;

/**
 * A class that determines the properties of a course.
 * 
 * @author Mike Kuehnle
 * @version 1.1
 */
public class Course 
{
	/** The course number */
	private String courseNum;
	
	/** The course name */
	private String courseName;
	
	/** The course credit */
	private double courseCredit;
	
	/** The course grade */
	private String courseGrade;
	
	/** The course GPA */
	private double courseGPA;
	
	/** The Grade object */
	private Grade grade;
	
	/**
	 * Constructs a new course.
	 * 
	 * @param crsNum The course number.
	 * @param crsName The course name.
	 * @param crsCredit The number of credits associated with a course.
	 * @param crsNumGrade The numerical grade earned in a course.
	 */
	public Course(String crsNum, String crsName, 
			String crsCredit, String crsGrade) 
	{
		courseNum = crsNum;
		courseName = crsName;
		courseCredit = Double.parseDouble(crsCredit);
		courseGrade = crsGrade;
		grade = new Grade(courseGrade);
		courseGPA = grade.getGPA();
	}
	
	/**
	 * Returns the course number.
	 * 
	 * @return A String literal specifying the course number.
	 */
	public String getCourseNumber()
	{
		return courseNum;
	}
	
	/**
	 * Returns the course name.
	 * 
	 * @return A String literal specifying the course name.
	 */
	public String getCourseName()
	{
		return courseName;
	}
	
	/**
	 * Changes the course name.
	 * 
	 * @param name A String literal specifying the name of the new course.
	 */
	public void setCourseName(String name)
	{
		courseName = name;
	}
	
	/**
	 * Returns the number of credits for a course.
	 * 
	 * @return A double value specifying the number of credits for a course.
	 */
	public double getCourseCredit()
	{
		return courseCredit;
	}
	
	/**
	 * Returns the letter grade for a course.
	 * 
	 * @return A String literal specifying the course grade.
	 */
	public String getCourseGrade()
	{
		return courseGrade;
	}
	
	/**
	 * Returns the letter grade for a course. If empty,
	 * course has not been taken.
	 * 
	 * @return A String literal specifying the letter grade.
	 */
	public double getCourseGPA()
	{
		return courseGPA;
	}
	
	/**
	 * Returns a String literal specifying course information.
	 */
	public String toString()
	{
		String message = "Course Number\tCourse Name\t\tCredit Hours\tGrade\tGPA\n\n";
		
		message = message + courseNum + "\t" + courseName + "\t\t" 
			+ courseCredit + "\t" + courseGrade + "\t" + courseGPA + "\n";
		
		return message;
	}
	
	/**
	 * Compares two courses to see if they have the same course number and name.
	 * Returns false if not, true if they are.
	 */
	public boolean equals(Object other)
	{
		if(!(other instanceof Course))
			return false;
		Course course = (Course)other;
		return courseNum.equals(course.courseNum) && courseName.equals(course.courseName);
	}
}

/**
 * Final Group Project
 */
package finalproject;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.StringTokenizer;

/**
 * Calls the Course class to create an array of courses
 * to be attached to a student.
 * 
 * @author Benjamin French
 * @version 1.1
 */
public class Transcript 
{
	/** An list of courses */
	private ArrayList<Course> courseList;
	
	/** The courses read in */
	private String[][]courses = new String[50][3];
	
	/** The student ID */
	private String studentID;
	
	/** The Course object */
	private Course course;
	
	/** The course name */
	private String courseName;
	
	/** The course number */
	private String courseNumber;
	
	/** The course credit */
	private String courseCredit;
	
	/** The course grade */
	private String courseGrade;
	
	/** The number of earned course credits */
	private double earnedCredit;
	
	/** An array of course GPAs */
	private double[] courseGPA;
	
	/** The cumulative GPA */
	private double gpa;

	/**
	 * Constructs a new Transcript.
	 * @throws IOException 
	 */
	public Transcript(String id) throws IOException 
	{
		courseList = new ArrayList<Course>();
		studentID = id;
		[COLOR="Red"]getCourses(studentID);[/COLOR]
		populateTranscript();
		calculateGPA();
		addEarnedCredit();
	}
	
	/**
	 * Totals the number of earned course credits.
	 */
	public void addEarnedCredit()
	{
		for(int i = 0; i < courseList.size(); i++)
		{
			if(!(courseList.get(i).getCourseGrade().equals("")))
				earnedCredit += courseList.get(i).getCourseCredit();
		}
	}
	
	/**
	 * Returns the earned credit.
	 * 
	 * @return A double value specifying the total earned credit.
	 */
	public double getEarnedCredit()
	{
		return earnedCredit;
	}
	
	/**
	 * Calculates the GPA for a transcript.
	 */
	public void calculateGPA()
	{
		for(int i = 0; i < courseList.size(); i++)
		{
			courseGPA[i] = courseList.get(i).getCourseGPA();
		}
		
		for(int i = 0; i < courseGPA.length; i++)
		{
			gpa += courseGPA[i];
		}
		gpa = gpa / courseGPA.length;	
	}
	
	/**
	 * Returns the GPA for a particular transcript.
	 * 
	 * @return A double value specifying the GPA.
	 */
	public double getGPA()
	{
		return gpa;
	}
	
	/**
	 * Populates the array list with course data.
	 */
	public void populateTranscript()
	{
		int row = 0;
		while(row < 23)
		{
			courseNumber = courses[row][0];
			courseName = courses[row][1];
			courseCredit = courses[row][2];
			courseGrade = courses[row][3];
			course = new Course(courseNumber, courseName, courseCredit, courseGrade);
			courseList.add(course);
			row++;
		}
	}
	
	/**
	 * Returns the transcript course information.
	 */
	public String toString()
	{
		String output = "COURSE NO:\tCOURSE NAME\t\tCOURSE CREDIT\tCOURSE GRADE\n\n";
		for(int i = 0; i < courseList.size(); i++)
		{
			output += courseList.get(i).getCourseNumber() + "\t";
			output += courseList.get(i).getCourseName() + "\t\t"; 
			output += courseList.get(i).getCourseCredit() + "\t";
			output += courseList.get(i).getCourseGrade() + "\n";
		}
		return output;
	}
	
	/**
	 * Compares two courses in an array.
	 * Returns false if not the same;
	 * true if they are.
	 */
	public boolean equals(Object other)
	{
		boolean isEqual = false;
		
		if(!(other instanceof Transcript))
			return false;
		Transcript trn = (Transcript)other;
		
		for(int i = 0; i < courseList.size(); i++)
		{
			isEqual = isEqual && this.courseList.get(i) == trn.courseList.get(i);
		}
		return isEqual;
	}
	
	/**
	 * Retrieves a list of courses based on the student ID.
	 * 
	 * @param ssn The student's ID.
	 * @throws IOException
	 */
	public void getCourses(String ssn) throws IOException
	{
		String filename = ssn;
		
		File file = new File(filename + ".csv");
		
		BufferedReader bufRdr  = new BufferedReader(new FileReader(file));
		String line = null;
		int row = 0;
		int col = 0;
	 
		//read each line of text file
		try
		{
			while((line = bufRdr.readLine()) != null && row < courses.length)
			{	
				StringTokenizer st = new StringTokenizer(line, ",");
				while(st.hasMoreTokens())
				{
					//get next token and store it in the array
					[COLOR="red"]courses[row][col] = st.nextToken();[/COLOR]
					col++;
				}
			col = 0;
			row++;
			}
		}
		catch(FileNotFoundException e)
		{
			System.out.println("Can't access file!");
			e.printStackTrace();
		}
		
	}
}

/**
 * Final Group Project
 */
package finalproject;

import java.io.IOException;

/**
 * Calls the Transcript class to get Course and Grade data.
 * 
 * @author Rashad Ayyash
 * @version 1.1
 */
public class Student
{
	/** The student ID */
	private String studentID;
	
	/** The student name */
	private String studentName;
	
	/** The student major */
	private String studentMajor;
	
	/** The earned credit hours */
	private double cHours;
	
	/** The cumulative GPA */
	private double gpa;
	
	/** The Transcript belonging to the student */
	private Transcript transcript;
	
	/**
	 * Constructs a new Student with an id, name, and major.
	 * 
	 * @param id The student ID.
	 * @param name The student name.
	 * @param major The student major.
	 * @throws IOException
	 */
	public Student(String id, String name, String major) throws IOException 
	{
		studentID = id;
		studentName = name;
		studentMajor = major;
		[COLOR="red"]transcript = new Transcript(studentID);[/COLOR]
		cHours = transcript.getEarnedCredit();
		gpa = transcript.getGPA();
	}
	
	/**
	 * Returns the student ID.
	 * 
	 * @return A String literal specifying the student ID.
	 */
	public String getID()
	{
		return studentID;
	}
	
	/**
	 * Returns the credit hours earned.
	 * 
	 * @return A double value specifying the credit hours.
	 */
	public double getCreditHours()
	{
		return cHours;
	}
	
	/**
	 * Returns the GPA.
	 * 
	 * @return A double value specifying the GPA.
	 */
	public double getGPA()
	{
		return gpa;
	}
	
	/**
	 * Returns the student's major.
	 * 
	 * @return A String literal specifying the major.
	 */
	public String getMajor()
	{
		return studentMajor;
	}
	
	/**
	 * Returns the student's name.
	 * 
	 * @return A String literal specifying the name.
	 */
	public String getName()
	{
		return studentName;
	}
	
	/**
	 * Returns the student academic information.
	 */
	public String toString()
	{
		String output = "Name: " + studentID + "\n";
		output += "Major: " + studentMajor + "\n";
		output += "Earned Credit Hours: " + cHours + "\t";
		output += "GPA: " + gpa + "\n";
		output += transcript.toString();
		return output;
	}
	
	/**
	 * Compares two Student objects.
	 * Returns false if not identical;
	 * true, if they are.
	 */
	public boolean equals(Object other)
	{
		if(!(other instanceof Student))
			return false;
		Student s = (Student)other;
		return studentID == s.studentID;
	}
}

/**
 * Final Group Project
 */
package finalproject;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Scanner;

/**
 * A Class designed to test the Student Transcript System.
 * 
 * @author Albert Hernandez
 * @version 1.1
 */
public class StudentRecord 
{
	/**
	 * Runs the program.
	 * 
	 * @param args A String literal specifying command-line parameters.
	 * @throws IOException 
	 */
	public static void main(String[] args) throws IOException
	{
		Scanner s = new Scanner(System.in);
		ArrayList<Student> students = new ArrayList<Student>();
		System.out.println("Please enter your social security number:");
		String ssn = s.nextLine();
		[COLOR="red"]students.add(new Student("1001","Albert Gabriel Hernandez", "Computer Science"));[/COLOR]
		
		for(int i = 0; i < students.size(); i++)
		{
			if(ssn == students.get(i).getID())
				students.get(i).toString();
		}
	}
}

I get the following error output:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 3
at finalproject.Transcript.getCourses(Transcript.java :199)
at finalproject.Transcript.<init>(Transcript.java:64)
at finalproject.Student.<init>(Student.java:47)
at finalproject.StudentRecord.main(StudentRecord.java :30)

Please help me resolve this issue.

[Vinod Mukundan]

Hi ,
It would be much easier if you format and put ur code inside code tag ..else highlight line Transcript.java :199. Its too much of code and most of us are too lazy to go through it . So reformat the code or highlight the exact line ur code is throwing the error.



warm regards
Vinod M
____________________________
Give me beans .........

[Eranga]

What you've on line 30 ?

StudentRecord.java :30

[Eranga]

Hi ,
It would be much easier if you format and put ur code inside code tag ..else highlight line Transcript.java :199. Its too much of code and most of us are too lazy to go through it . So reformat the code or highlight the exact line ur code is throwing the error.



warm regards
Vinod M
____________________________
Give me beans .........

That's try to be specific as much as possible. Posting such a long codes are not easy to read. Because of the members are not run your code and find bugs, instead they go through a dry-run. So posting relevant is the key. Good luck! :)

[ahernandez980]

StudentRecord.java : 30 adds a new Student to the students arraylist.

[Vinod Mukundan]

Hi ,

private String[][]courses = new String[50][3]; in Transcript class


Define it as

private String[][]courses = new String[50][4];


as you have 4 values to be inserted. Read about Arrays when you get time :)


warm regards
Vinod M
____________________________
Give me beans .........

[Eranga]

StudentRecord.java : 30 adds a new Student to the students arraylist.

That's end at this line, seems you've track it correctly.

courses[row][col] = st.nextToken();

In each adding check the size of the sources, and the index you are involve at that time in your code. Did you do that?