macOS Java help with ArrayList

[prostuff1]

I am creating a simple class that takes in a students first name and last name.

the constructor for this is Student myStudent = new Student (first name, last name). I have to public methods that can be called. They are getName(), which returns the persons full name as a string and getEmailAddress() which returns there e-mail address as a string.

The problem i am having is that we need to keep track of multiple last names to change a number. The e-mail address should turn out something like lastname.1@school.edu and if there are multiple people with the same last name then it would be lastname.2@school.edu.

I can create and ArrayList<String> that adds in the last names. I think what is happening is that the ArrayList is being "recreated" from scratch when I do my myStudent = newStudent(first name, last name).

Anyway, here are the two files i am working with:

import java.util.ArrayList;

public class Student 
{
	private String firstName="", lastName="";
	ArrayList<String> lastNames = new ArrayList<String>();
	
	public Student(String fName, String lName)
	{
		this.firstName = fName;
		this.lastName = lName;
	}
	
	private static String createEmailAddress(String firstName, String lastName, ArrayList<String> lastNames)
	{
		String studentsEmail = "";
		int number = 0;
		
		lastName = lastName.toLowerCase();
		
		for(int index=0; index < lastNames.size(); index++)
		{
			if(lastName.equals(lastNames.get(index)))
			{
				number++;
			}
			
		}
				
		studentsEmail = lastName + "." + (number+1) + "@osu.edu";		
		
		return studentsEmail;
	}
	
	public String getName()
	{
		String studentsName = this.firstName + " " + this.lastName;
		
		return studentsName;
	}
	
	public String getEmailAddress()
	{
		String emailAddress = createEmailAddress(this.firstName, this.lastName, lastNames);
		
		return emailAddress;
	}

}

import java.util.ArrayList;
import java.util.Scanner;

public class TestDriver 
{
	public static void main(String[] args) 
	{
		char keepgoing = 'y', answer; //chars for while loop and user input
		Scanner keyboard = new Scanner(System.in); //for getting user input from keyboard
		String selection, firstName="", lastName=""; //the string input and the number to be changed
		Student studentName = new Student(firstName, lastName);
		
		while(keepgoing != 'q')
		{
			//Selections for the user to choose from
			System.out.println("Please select from the following options: ");
			System.out.println("                          enter name [e]: ");
			System.out.println("              get students full name [n]: ");
			System.out.println("         get students e-mail address [a]: ");
			System.out.print("                                quit [q]: ");

			//get input and compare the first character
			selection = keyboard.nextLine();	
			answer = selection.charAt(0);

			System.out.println();

			if(answer == 'e')
			{
				//get the natural number as a string so it can be arbitrarily long to start
				System.out.print("Please enter the first name: ");
				firstName = keyboard.nextLine();
				
				System.out.print("Please enter the last name: ");
				lastName = keyboard.nextLine();
				System.out.println();
				
				studentName = new Student(firstName, lastName);
			}
			else if(answer == 'n') //increment 
			{
				//call getName method
				System.out.println("The students full name is: " + studentName.getName() + "\n");
				
			}
			else if(answer == 'a') //decrement
			{
				//call getEmailAddress method
				System.out.println("The students e-mail address is: " + studentName.getEmailAddress() + "\n");
			}
			else if(answer == 'q')//quit
			{
				//set keepgoing so while loop stops
				keepgoing = 'q';

				//print out exit message
				System.out.println("Quitting Program");
			}
			else //user entered an unknown option
			{
				//print message to the screen
				System.out.println("You selected an unknow option please choose again\n");
				//set keepgoing to answer so while loop continues
				keepgoing = answer;
			}
		}
	}
}

What I need is for the ArrayList in the Student.java file to only be initialized once (when the first Student myStudent call is made).

I can do this easy enough in the test driver file but it does not work for what i need to do. I can not pass anything across

 

[prostuff1]

Never Mind

NEVER MIND

In my stupidity (and sleepiness) I forgot what i was doing.

For anyone that is wondering I just needed to put the word static in from of the line:

ArrayList<String> lastNames = new ArrayList<String>();

so that it looked like:

static ArrayList<String> lastNames = new ArrayList<String>();