How to do something at a specific in-game time?

I need my plugin to check the time every tick etc and if the time is 16000 it does something and if the time is 18000 it does something else. How would I go about doing this?

 

If you have a Player "p":

p.getWorld().getTime();

 

No I need it to check automatically without an event.

 

Then use. Bukkit.getServer().getWorld("NAME").getTime();

 

getServer().getScheduler().scheduleSyncRepeatingTask(this, new Runnable() {
public void run() {
// Check if nighttime or daytime
if (Bukkit.getWorld("WorldName").getTime() >= 14000) NightTime = true; else NightTime = false;
}}, 20L, 20L);

 

There's no time change event, so the above method of using a syncRepeatingTask is probably the best way of going about it.