Need a simple example of Scheduler Programming

Basically, I want to know how to make a plugin that counts seconds from 1 to 3

Something like:

if (commandLabel.equalsIgnoreCase("ThreeSecondTimer"))
{
//Something involving Scheduler Programming
}


I'll be posting this information directly to the developer wiki. Thank you.

P.S. I checked http://wiki.bukkit.org/Scheduler_Programming but the tutorial code there is heavily lacking in comments, to the point I'm not sure it covers what I'm asking about

 

Code:

public int n;
 
Bukkit.getScheduler().scheduleSyncRepeatingTask(this, new Runnable() {
    public void run() {
        if (n >=  4){
            n = 0;
        }
        n++
    }
}, 20, 20);

Theres probably even a way to make it simpler LOL

 

Code:

Bukkit.getServer().getScheduler()
                .scheduleAsyncDelayedTask(this, new Runnable() {
 
                    public void run() {
                        Delayed Task
                    }
                }, (Delay in MS)L);

 

So int n is accessible even after sending the Runnable to the Scheduler? I was thinking that scheduler accepts Runnables and then runs them independently of the function that Schedules them. Is that not how it works?

Also, what are the 20's in } 20, 20); for?

 

sorry, you should actually change public int n; to public final int n; - Runnables require a final. And the 20s are the duration in ticks between repeats. A tick is 1/20th of a second.

 

But then you wont be able to change / update n
You just have to put it outside of the whole method

 

yeah... public int n; lol
im working on a plugin right now thats making me frustrated.... so im not really putting much thought into it.

 

Whats the plugin do?!

 

This is just an educated guess, but this might work:

Code:java

public final int[] array = {1, 2, 3};
 
Bukkit.getScheduler.scheduleSyncRepeatingTask(this, new Runnable(){
    public void run(){
        for(int n : array){
            if(n == 3){
                //do stuff(You counted to 3!)
            }
            break;
        }
    }
}, 0, 20);

EDIT: Thinking about it some more, this may just put it in an endless loop...

 

Chiller
Makes a cursor follow all player positions on any map. Basically making the xbox360 maps (if you've played it before). I am even adding colors for players with permission. And it deals with a lot of performance, math, and tedious stuff.

 

This is client side right?

 

Chiller
Nope, server side. Bukkit has an API for changing maps

 

Wait a cursor as in what? I thought you were saying like a minimap.

 

The white arrow on a map when you look at it is a cursor. I am adding colored cursors in red blue and green for all players in the game, to everyones maps. I am also going to be making a command for creating a map with a much larger scale, which means you can see more of the world... etc

 

What you're looking for, if you haven't found it already, is something like this:

Code:java

 
Bukkit.getScheduler().scheduleSyncRepeatingTask(this [as in your plugin instance], new Runnable()
{
     public void run()
          {
               updatePlayerPositionsOnMap();
          }
}, 60, 60);
 

Long story short, here's the rundown:

• You schedule it with an instance of your plugin, and an instance of a runnable. Usually, it's an anonymous inner class--but sometimes it helps to create your own Runnable class so you can pass variables into the scheduler (avoiding a lot of final issues)
• At the end, you have 2 variables. First variable is going to be the delay in ticks, the second is going to be how often your task repeats. There are 20 ticks in a single second, roughly, so if you want a 3 second delay with a 3 second repeating interval, you'd give 60 as both of the variables.

Other than that, everything is fairly straight forward.

 

This looks like it should work to me. I'll have to test it later. It's not really necessary in the plugin I'm making, but it should be a nice touch. I do feel like bumping this one more time, though, to see if anyone can say for sure whether or not this is how a runnable works.

 

Thumbz
Just on a little side note, i just realized it should be getScheduler(), not getScheduler. Not too big, since Eclipse would easily catch this, but just thought I would point that out.

 

Code:java

Bukkit.getScheduler.scheduleSyncRepeatingTask(this, new Runnable(){
public static int n;
public void run(){
if(n==0){
n = 1;
}
System.out.println(n);
n++;
}
},20L,20L);
 
 
//20L means 1 sec in ticks
 

EDIT: tested and works

 

4thegame3 Public static fields are almost always wrong. This is certainly the case when using anonymous classes.