Schedulers

ya thats the one thing i have an issue with, the for loop...
with this, the for loop is like invisible, whether it is within, or around the statement :/
(by the use of the for loop, i mean so that the lightning can keep striking over and over a few times)

 

I think what's needed is to take a step back and re-evaluate the problem. You don't want to use a for or while loop here. You're working with event-driven programming, so you can't just take over the server thread to run a for loop with a delay (but I suspect you know that by now )

@V10lator 's example is a good way to do it (I'm not sure getting a uuid is necessary, when scheduleSyncRepeatingTask() returns a unique ID anyway, but it's a valid approach). You basically need to set up a sync repeating task (using the Scheduler scheduleSyncRepeatingTask() method) which calls a lightning strike in the target object's run() method, and then cancels itself after a given number of calls to the method.

The important thing to realise here is that this is event-driven, not straightforward procedural, programming. The code you write that responds to events (and I'm including scheduler callbacks in this) needs to work as quickly as possible to avoid creating server lag. Bearing in mind that one server tick is 50ms, all plugin event handlers need to complete in at most 50ms minus some server overhead - otherwise you'll get the dreaded "Can't keep up!" messages in your server log.

 

The problem is to give that ID to the task, so it can cancel itself. That's why I'm using a HashMap with a UUID as the key and the task ID as value. Possibly something like this would work, too:

Code:java

TestTask task = new TestTask(this);
task.setPid(getServer().getScheduler().scheduleSyncRepeatingTask(this, task, 1L, 1L));

Code:java

public class TestTask implements Runnable
{
  private final YourPlugin plugin;
  private int pid;
  public TestTask(YourPlugin plugin)
  {
    plugin = plugin;
  }
  public void run()
  {
    plugin.getServer().getScheduler().cancelTask(pid);
  }
  public void setPid(int pid)
  {
    this.pid = pid;
  }
}

 

Personally, I'd do it like this (untested, apologies for any typos):

Code:java

 
public class LightingStrike implements Runnable
{
  private int taskId;
  private int repeats;
  private Location loc;
 
  public LightningStrike(Location loc, long delay, int repeats)
  {
    this.loc = loc;
    this.repeats = repeats;
 
    taskId = Bukkit.getServer().scheduleSyncRepeatingTask(plugin, this, 1L, delay));
  }
  public void cancel() {
    Bukkit.getServer().getScheduler().cancelTask(taskId);
  }
 
  public void run() {
    if (repeats-- <= 0) {
      cancel();
    } else {
      loc.getWorld().strikeLightning(loc);
    }
  }
}
 

Then you can say something like:

Code:java

 
// schedule 10 strikes, 0.25 seconds apart
LightningStrike ls = new LightningStrike(loc, 5L, 10);
 

You may or may not want to keep a copy of the return value. You might want the ability to cancel the strike partway through, for example (using ls.cancel()).

There's a lot that could be added to this, e.g.:

• Have lightning strikes randomly within a configurable radius around loc
• Configurable start delay
• Configurable autostart (i.e. don't start until a start() method is called)
• Configurable whether it does real damage or just for show

But that's a good basis to work from

 

at the moment, i think most of the code you guys have posted (which are amazing ) is probably unnecessary. i think i can figure it out if i know how to stop a repeating task. (you guys probably mentioned that within your code, or posts, but im in a rush so...)

 

sorry for the late reply, but, i can't seem to get this to work within and onCommand statement
(yes, i have been experimenting)

 

Paste what you have so far, so we can help

 

Code:java

 
[USER=4618]tips48[/USER] this is what i had before in an on command statement

 

We need the updated code

 

before this was within a for loop, a if statement, and a while loop.
also, i have been switching between a repeating task, and a delayed task.
here is what i have (had):

Code:java

 
plugin.getServer().getScheduler().scheduleSyncDelayedTask([B]this[/B].plugin, [B]new[/B] Runnable()
{
[B]public[/B] [B]void[/B] run() 
{
world.strikeLightningEffect(loc);
world.createExplosion(loc, 0);
}
}, 20L);

 

nunber1_Master
That code will wait one second, strike a lightning effect and create a explosion. Is that what you want?

 

no
yes i know what it does
what im looking for is something that will strike lightning x many times, with a delay of 3L (not 20L, 20L was just because im fooling around with it)

 

Multiple people already gave you the code above.
Check the posts from desht and V10lator , and if you can't implement it yourself you might want to take a couple more java tutorials

 

thats what ive been doing
its just hard to do that within onCommand
well, back to more studying! :/

 

It shouldn't be that hard from onCommand...Your given the code more than once. Specifically:

Code:java

 
TestTask task = new TestTask(this);
task.setPid(getServer().getScheduler().scheduleSyncRepeatingTask(this, task, 1L, 1L));
 

 

i know
im just trying to it differently

i feel stupid, the answer is probably staring me right in the face, yet i dont understand it
to me, the easiest way would be this, but doesnt work:

Code:java

 
for(int counter=0;counter<=20;counter++)
{
plugin.getServer().getScheduler().scheduleSyncDelayedTask(this.plugin, new Runnable()
{
public void run()
{
world.strikeLightningEffect(loc);
world.createExplosion(loc, 0);
}
}, 20L);
}
 

since that doesn't work, in my mind i just want to do this, about 20 times:

Code:java

 
plugin.getServer().getScheduler().scheduleSyncDelayedTask(this.plugin, new Runnable()
{
public void run()
{
world.strikeLightningEffect(loc);
world.createExplosion(loc, 0);
}
}, 20L);
 
EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

This will strike 21 lightnings in the same tick...
Also I'll bet you have a problem transferring "world" to the task...

 

no
i have tried just that once, and it works fine
except i cant get it to repeat it

 

Cause a delayed task != a repeating task. If you start a delayed task 21 times with the same delay it will execute 21 times at the same tick = 21 lightning strikes in one tick...

 

as for as my testing has gone (on a server), and what i know, it has not struck lightning 21 times in about 1 tick