Tutorial Creating cooldown in event

I just want to help those who just started coding and dont know how to create cooldowns

Code:

public class EDelay implements Listener
{
    public HashMap<String, Long> cooldown; // creating hashmap named cooldown
    Main plugin;
    public EDelay(Main passedPlugin) // This class isn't in the main class so connecting it
    {
        this.plugin = passedPlugin;
        cooldown = new HashMap<String, Long>(); // declaring cooldown so it can be used in event
    }
   
    @EventHandler
    public void onProjectileLaunch(ProjectileLaunchEvent e)
    {
        int seconds = 5; // how much cooldown we want
        Projectile pro = e.getEntity();
        if(pro.getShooter() instanceof Player)
        {
            if(pro.getType() == EntityType.ENDER_PEARL) // if player throws ender pearl
            {
                Player player = (Player) pro.getShooter();
                if(cooldown.containsKey(player.getName())) // if cooldown has players name in it (on first trow cooldown is empty)
                {
                    long timer = (cooldown.get(player.getName())/1000 + seconds) - System.currentTimeMillis()/1000; // geting time in seconds
                    if(!(timer < 0)) // if timer is still more then 0 or 0
                    {
                        player.sendMessage("You have to wait for " + timer + " seconds!");
                        e.setCancelled(true);
                    }
                    else // if timer is done
                    {
                        cooldown.remove(player.getName()); // removing player from HashMap
                    }
                }
                else // if cooldown doesn't have players name in it
                {
                    cooldown.put(player.getName(), System.currentTimeMillis()); // adding players name + current system time in miliseconds
                }
            }
        }
    }
}

First we get what time we added player into HashMap then we divide it with 1000 so we get seconds and add how many seconds we want to have.
Then we just subtract it with the current time in seconds(which is increasing over time)

Code:

long timer = (cooldown.get(player.getName())/1000 + seconds) - System.currentTimeMillis()/1000;

 

Moved to Resources

 

Umm please fix the following:
- access modifiers, don't forget the private modifier!
- for efficiency purposes don't initialize the delay time in seconds each time the event executes instead have a constant field to hold this value.
- isn't !(timer<0) the same as timer >= 0 ?
Also consider using the TimeUnit enum to help yourself :- )

 

@mine-care tnx for suggestion im still learning

 

@NortherKnight why are you making resources without good knowledge of the bukkit api

 

@MCMatters because so many cooldown tutorials are just way to complicated for new programmers

 

This is as complicated as the other ones, whats the problem with just using a simple scheduler.

Also why are you defining the hashmap in a constructor and why is your hashmap public?
Also why are you defining the main class in a constructor if you aren't even using it?

 

Cool

 

This creates unneccessary lagg on the server, just save the last time stamp the player used the item, and cancel the event, if a certain amount of time didn't passed away. Or connect it to a wither bossbar loading, that's what I do most of the time.

 

@mcdorli Where is that lag coming from? If statements? Subtracting numbers?