exampletimer.java

import net.menoni.rd.RuntimeDebugger;
import net.menoni.rd.model.Debugger;
import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.command.BlockCommandSender;
import org.bukkit.command.CommandSender;
import org.bukkit.command.ConsoleCommandSender;
import org.bukkit.entity.Player;
import org.bukkit.scheduler.BukkitTask;
import org.bukkit.util.Vector;

public class exampletimer implements Debugger, Debugger.Stoppable, Runnable {

    private BukkitTask timerTask;
    private Player invoker;

    public void debug(RuntimeDebugger plugin, CommandSender cs) {
        if (!(cs instanceof Player)) {
            cs.sendMessage("Command can only be used by a player");
            return;
        }
        this.invoker = (Player) cs;
        timerTask = Bukkit.getScheduler().runTaskTimer(plugin, this, 2L, 2L);
        cs.sendMessage(ChatColor.YELLOW + "Up up and away! Crouch to stop going up!");
    }

    public void run() {
        if (this.invoker == null || !this.invoker.isOnline()) {
            // make sure the script doesn't crash if the player disconnects
            this.stop();
        }
        // if the player is sneaking, don't change their velocity
        if (this.invoker.isSneaking()) {
            return;
        }
        // otherwise, make them go up up up!
        this.invoker.setVelocity(this.invoker.getVelocity().clone().add(new Vector(0d, 1d, 0d)));
    }

    public void stop() {
        if (this.timerTask != null) {
            this.timerTask.cancel();
            this.timerTask = null;
        }
    }
}