ArrayListTestCode.java

import java.util.ArrayList;

public class YourClassNameHere {
  
	    public static void main(String[] args) {
	      
	      ArrayList<Player> inGamePlayers = new ArrayList<Player>();
	      inGamePlayers.add(new Player("Griff"));
	      
	      String newUsername = "Polak";
	      
	      for (Player p : inGamePlayers) {
	        
	        if (newUsername == p.username) {
	          System.out.println(p.username+" reconnected!");
	          break;
	        }
	        
	        inGamePlayers.add(new Player(newUsername));
	      }
	      
	      for (Player p : inGamePlayers) {
	        System.out.println(p.username);
	      }
	      
	      
	
	    }
	}
	
class Player {
  
  public String username;
  
  public Player(String username) {
    this.username = username;
  }
}