Setting player locations when a player leaves

So I have a plugin set up for King of The Ladder, so when players join they go to a pod. What the code basically does is when a player joins, they are taken to a pod, and then a integer is added by 1 each time a player joins. The player goes to a pod based on what number the integer is at, example int == 1, pod 1, int == 2, pod 2, ect. The only problem I have is when a player leaves, I want it so when the last player joins, they can fill the pod back up to where the player that left was. How would you do that?

P.S. I dont have the code I got a short little power outage and my computer turned off (Screw Desktops!).
But ill make an example of what the code looked like:

Code:

@EventHandler
public void join(PLayerJoinEvent e)
int join = 1;

player p = e.getPlayer();

if (join == 1){
//teleports player to pod 1
join = 2;
}
if (join == 2){
//teleports player to pod 2
join = 3;
}
//ect.

 

I would say use a combination of a boolean array and a map for speed:

Code:java

public class ExamplePodThing {
 
    private final Map<UUID, Integer> seat = new HashMap<>();
    private final boolean[] occupied;
 
    public ExamplePodThing(int numOfPods) {
        this.occupied = new boolean[numOfPods];
    }
 
    /**
     * Called when a player joins
     */
    public void join(Player p) {
        int pod = this.getNextPod();
        //set the player's pod using either pod or pod+1 (since it's 0-based index)
        //But be consistent
        this.occupied[pod] = true;
        this.seat.put(p.getUniqueId(), pod);
    }
 
    /**
     * Finds the next pod number
     *
     * @return The next pod number, or -1 if none are available
     */
    public int getNextPod() {
        for (int w = 0; w < this.occupied.length; w++) {
            if (!this.occupied[w]) {
                return w;
            }
        }
        return -w;
    }
 
    /**
     * Called when a player leaves
     */
    public void leave(Player p) {
        this.occupied[this.seat.remove(p.getUniqueId())] = false;
    }
 
}