import java.io.*;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

public class TextFile
{
    public static BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
    public static String[] person;
    public static String[] tempPerson;
    public static String[] sepTemp;
    public static int xCtr;

    public static void mainMenu()
    {
        System.out.println("1] Insert");
        System.out.println("2] Delete"); ////////////////
        System.out.println("3] Exit");///////////////
    }
public static void insertData() throws IOException ///insert
    {
        System.out.print("Enter name: ");
        String pName = stdin.readLine();
        String temp;
        
        if (xCtr != 0)
        {
    
            temp =tempPerson[0] + ", " + pName;    
                
        }
        else
        {
            temp = pName;
            xCtr = 1;
        }    
            
        FileOutputStream x = new FileOutputStream("myTextFile.dat");
        ObjectOutputStream y = new ObjectOutputStream(x);
        y.writeObject(new String[] {temp});
        
        System.out.println("New Entry Updated...");

        y.close();
    }
    
    public static void displayInitData() //displayInitial data
    {
        try
        {

                FileInputStream x = new FileInputStream("myTextFile.dat");
                ObjectInputStream y = new ObjectInputStream(x);
                tempPerson = (String[])(y.readObject());
                
                sepTemp = new String[100000];
                sepTemp = tempPerson[0].split(", ");
            
            
                int i = 0;
                
                do
                {
                    person[i] = sepTemp[i];
                    i = i + 1;
                }
                while(i<sepTemp.length);
                
            
                xCtr = i;
                
            
        }
        catch(Exception m)
        {
            m.getMessage();
        }
        
    }
    
    public static void displayData()         //display data
    {
        int i=0;
        
        do
        {
            System.out.println(sepTemp[i]);
            i = i + 1;
        }
        while(i<sepTemp.length);        
    }
public static void main (String[] args) throws IOException, Exception
    {
        int choiceMenu;
        
        person = new String[100000];
        tempPerson = new String[100000];
        displayInitData();
    
        do
        {
            mainMenu();
            System.out.print("Enter Choice: ");
            choiceMenu = Integer.parseInt(stdin.readLine());
            
            switch(choiceMenu)
            {
                case 1:    displayInitData();
                        insertData();
                        break;
                case 2:delete();
                        break;
                                case 3: update();break;
case 4:
                        if (xCtr > 0)
                        {
                            displayInitData();
                            displayData();
                        }
                        else
                            System.out.println("No Record");
                        break;
                default:
            }
        }
        while(choiceMenu!=3);
        
    }
}