Thread: Trying to read objects from file into ArrayList

I am working on my own personal project where you keep a record of Player objects in a file. I have created a way create a new file and add Player objects to it, or open an existing file and add Player objects. However, to delete a Player object from an existing file, I have to read the Player objects from that file into an ArrayList. Then delete the desired Object, preferably using the remove() method. Once that is done, I write the ArrayList into the file again. This time without the Objects that I removed.

However, I keep getting this error:

HTML Code:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
	at roster.Team.delete(Team.java:98)
	at roster.Driver.main(Driver.java:26)

I can't get my code to work without solving this error. It would be much appreciated if someone could help me.

Run my code below to see the issue:

HTML Code:

package roster;

import java.io.IOException;

import java.util.Scanner;

public class Driver {

	public static void main(String[] args) throws IOException {

		Team t1 = new Team();
		System.out.println("To create a new roster, type 1");
		System.out.println("To add to an existing roster, type 2");
		System.out.println("To remove a player from a roster, type 3");
		
		Scanner scan = new Scanner(System.in);
		int choice = scan.nextInt();
		
		if(choice == 1){
			t1.input();
		}
		if(choice == 2){
			t1.add();
		}
		if(choice == 3){
			t1.delete();
		}
		scan.close();

	}

}

HTML Code:

package roster;

import java.io.BufferedWriter;

import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.stream.Stream;
import java.io.ObjectInputStream;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.io.FileInputStream;

import java.io.*;

public class Team {

	ArrayList<Player> x = new ArrayList<Player>();

	public Team(){
		this.x = new ArrayList<>();
	}
	Scanner scan = new Scanner(System.in);
	public void input() throws IOException {
		int num_people;
		System.out.print("Name of file (A file that does not exist will be automatically created): ");
		String name;
		name = scan.next();
		System.out.print("# of people on roster? ");
		num_people = scan.nextInt();
		System.out.println("Enter first, last, goals, caps, and assists:");
		for(int i=0; i<num_people; i++){
			String fstname2 = scan.next();
			String lstname2 = scan.next();
			String goals = scan.next();
			String caps = scan.next();
			String assists = scan.next();
			x.add(new Player(fstname2,lstname2,goals,caps,assists));
		}
		scan.close();
		System.out.println("Done.");
		
		BufferedWriter writer = new BufferedWriter(new FileWriter(name));
	    for(Player p : x)
	        if(p != null){
	            writer.write(p + "\n");
	            writer.newLine();
	        }
	    writer.close();
	}
	public void add() throws IOException {
		System.out.println("Enter the name of the file that you wish to add information to: ");
		String name = scan.next();
		File w = new File(name);
		if(w.exists())
		{
		    System.out.println("How many people would you like to add? ");
			int num_people = scan.nextInt();
			System.out.println("Enter first, last, goals, caps, and assists:");
			for(int i=0; i<num_people; i++){
				String fstname2 = scan.next();
				String lstname2 = scan.next();
				String goals = scan.next();
				String caps = scan.next();
				String assists = scan.next();
				x.add(new Player(fstname2,lstname2,goals,caps,assists));
			}
			System.out.println("Done.");
			
			BufferedWriter q = new BufferedWriter(new FileWriter(w, true));
		    for(Player p : x){
		    	q.write(p + "\n");
		    	q.newLine();
		    }
		    q.close();
		}
		else{
			System.out.println("File does not exist.");
		}
	}
	public void delete() throws IOException {
		System.out.println("Enter the name of the file that you wish to delete information from: ");
		String name = scan.next();
		File w = new File(name);
		if(w.exists())
		{
	        try {
	            Scanner sc = new Scanner(w);

	            ArrayList<Player> x = new ArrayList<Player>();

	            while(sc.hasNextLine()){
	                String line = sc.nextLine();
	                String[] details = new String[4];
	                details = line.split(" ");
	                String fstname = details[0];
	                String lstname = details[1];
	                String goals = details[2];
	                String caps = details[3];
	                String assists = details[4];
	                //int age = Integer.parseInt(details[2]);
	                Player p = new Player(fstname,lstname,goals,caps,assists);
	                x.add(p);
	            }

	            for(Player p: x){
	                System.out.println(p.toString());
	            }

	        } catch (FileNotFoundException e) {         
	            e.printStackTrace();
	        }

		    System.out.println("How many people would you like to remove? ");
			int num_people = scan.nextInt();
			System.out.println("Enter first, last, goals, caps, and assists:");
			for(int i=0; i<num_people; i++){
				String fstname2 = scan.next();
				String lstname2 = scan.next();
				String goals = scan.next();
				String caps = scan.next();
				String assists = scan.next();
				x.remove(new Player(fstname2,lstname2,goals,caps,assists));
			}
			System.out.println("Done.");
			System.out.println();
			for(int i=0;i<x.size();i++){
		    	System.out.println(x.get(i));
		    }
			BufferedWriter q = new BufferedWriter(new FileWriter(w));  //The Object I "deleted" still shows up in file
		    for(Player p : x){
		    	q.write(p + "\n");
		    	q.newLine();
		    }
		    q.close();
		}
		else{
			System.out.println("File does not exist.");
        }
	}

HTML Code:

package roster;

public class Player {

	String fstname, lstname, goals, caps, assists;
	
	public Player(String fstname, String lstname, String goals_, String caps_, String assists_) {
		super();
		this.fstname = fstname;
		this.lstname = lstname;
		this.goals = goals_;
		this.caps = caps_;
		this.assists = assists_;
	}
	public String toString(){
		return fstname + " " + lstname + " " + goals + " " + caps + " " + assists;
	}
	public String getFstname() {
		return fstname;
	}
	public void setFstname(String fstname) {
		this.fstname = fstname;
	}
	public String getLstname() {
		return lstname;
	}
	public void setLstname(String lstname) {
		this.lstname = lstname;
	}
	public String getGoals() {
		return goals;
	}
	public void setGoals(String goals) {
		this.goals = goals;
	}
	public String getCaps() {
		return caps;
	}
	public void setCaps(String caps) {
		this.caps = caps;
	}
	public String getAssists() {
		return assists;
	}
	public void setAssists(String assists) {
		this.assists = assists;
	}
}

If you look at line 95, I made the size of the array to hold 5 elements.

String[] details = new String[4];

I fixed the code to say 4 elements instead of 5.

This line only returns the first object I have in the file:

HTML Code:

System.out.println("details="+ java.util.Arrays.toString(details));

Does this mean that the details array only holds one line?

I did

This is my output:

details=[Simon, Markus, 0, 0, 0]
details=[]

That's the problem, it does not read the next two lines. It only reads the first line, and I want to get it to read ALL of the lines in the file. And put all of those objects into an ArrayList, so that I can then delete one from the keyboard.