Micro Cooldown Class

Cooldown.java

import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.function.Predicate;
import java.util.function.Supplier;

public class Cooldown {

	private static List<Cooldown> cooldowns = new ArrayList<>();
	public static Map<UUID, Cooldown> perPlayerCooldown = new HashMap<>();
	private long cooldown;
	private long startingTime;
	private Supplier<Long> currentTime = () -> System.currentTimeMillis();

	public Cooldown(int time, TimeUnit timeUnit) {
		this.cooldown = timeUnit.toMillis(time);
		this.startingTime = System.currentTimeMillis();

		cooldowns.add(this);
	}

	public Cooldown(int time, TimeUnit timeUnit, Runnable startExecution) {
		this(time, timeUnit);
		if (startExecution != null)
			startExecution.run();
	}

	public Predicate<Long> busy() {
		return t -> currentTime.get() < startingTime + t;
	}

	public void ifFinished(Runnable execute) {
		if (isFinished()) {
			cancel();
			if (execute != null)
				execute.run();
		}
	}

	private boolean isFinished() {
		return currentTime.get() > startingTime + cooldown;
	}

	public long getCooldownTime(TimeUnit as) {
		return as.convert(cooldown, TimeUnit.MILLISECONDS);
	}

	public long getStartTime() {
		return startingTime;
	}

	public Supplier<Long> getCurrentTime() {
		return () -> currentTime.get() - startingTime + cooldown;
	}

	public void cancel() {
		cooldowns.remove(this);
	}

	public static List<Cooldown> getRunningCooldowns() {
		return cooldowns;
	}

	public static void cancelAllCooldowns() {
		cooldowns.forEach(cooldowns::remove);
	}
}