Cannot Schedule an Object that Extends BukkitRunnable a Second Time after Canceling - scheduler

Question

So it seems that I can't schedule an object that extends bukkitrunnable again even though the first scheduled instance is canceled.
for example, the following code is executed when the Player right clicks
try {
blizzard.cancel();
}
finally {
blizzard.runTaskTimer(Main.plugin, 0, 1);
}
Where blizzard is an object that extends BukkitRunnable
The first time runs just fine but never runs again no matter how many times I right click. What am I doing wrong?
**Each player can have their own blizzard object. When a player right clicks with a hoe in hand, Blizzard drops a snowball at a random location around that player. Blizzard drops one snowball every run command and runs until it reaches a set number of runs. Then blizzard cancels itself. However, scheduling Blizzard to run while it is already running throws an IllegalStateException, meaning I have to cancel the current Blizzard to schedule it to run again. The problem is that doing so doesn't seem to properly schedule Blizzard to run again - it only runs the very first time it is scheduled.

Answer 1

By default, Bukkit does not allow runnables to be rescheduled even after they are cancelled. If you learned about Threads then you will remember that when a Thread is terminated, it can not be restarted. Bukkit follows this same logic when it comes to Runnable instances. A terminated (cancelled) Runnable can not be restarted. You must create a new Runnable instance if you wish to have that event occur again.
To have a Runnable run multiple times, you are on the right track. The BukkitScheduler.runTaskTimer method will run a task repeatedly until it is cancelled. If in your Listener you run Bukkit.getScheduler().runTaskTimer(Main.plugin, new Blizzard(), 0, 1); your Blizzard object will run repeatedly until it cancels itself. (You can also use blizzard.runTaskTimer(Main.plugin, 0, 1); from within the Blizzard constructor to automatically schedule the Runnable when it is created.)
If you keep an internal counter for how many times it has run, and increment that timer every run() method, you can cancel your Runnable after it has run a certain amount of times.