每5分钟清除掉落的物品

Question

I am coding a Spigot 1.8.9 plugin and am trying to clear drops every 5 minutes but before the items are cleared I want to give a 60, 30, 15, 10, 5, 3, 2, 1 second warning then have them cleared.

I tried using the following but it doesn't have the countdown warning.

public static void startDropTimer() {
    Bukkit.getScheduler().scheduleSyncRepeatingTask(MyPlugin.getPlugin(), new Runnable() {

        @Override
        public void run() {
            clearAllDrops();
        }
    }, 6000, 6000);
}

How can I implement the warning countdown before clearing the drops?

Answer 1

You can create a timer variable to store passed time

long remainingTimeInSeconds = 300; //5 minutes

Then update your task to reduce this timer every 20 ticks (20 ticks = 1 second in Bukkit). With the update task, make checks on your timer variable to verify if a message should be sent or if the drops should be cleared:

Bukkit.getScheduler().scheduleSyncRepeatingTask(MyPlugin.getPlugin(), new Runnable() {

    @Override
    public void run() {
        currentTimeInSeconds--;

        switch(remainingTimeInSeconds) {
           case 60:
           case 30:
           case 15:
           case 10:
           case 5:
           case 3:
           case 2:
           case 1:
           //Send message remainingTimeInSeconds seconds left until drops are cleared!
           break;

           case 0:
           clearAllDrops();
           remainingTimeInSeconds = 300; //Reset your timer
           break;             
        }    

    }
}, 20L, 0);