bentobox/src/main/java/world/bentobox/bentobox/api/user/Notifier.java

60 lines
2.0 KiB
Java

package world.bentobox.bentobox.api.user;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import org.eclipse.jdt.annotation.NonNull;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
/**
* Utilities class that helps to avoid spamming the User with potential repeated messages
* @author Poslovitch, tastybento
*/
public class Notifier {
/**
* Time in seconds before {@link #notificationCache} removes the entry related to the player.
*/
private static final int NOTIFICATION_DELAY = 4;
private record Notification(String message, long time) {}
private final LoadingCache<User, Notification> notificationCache = CacheBuilder.newBuilder()
.expireAfterAccess(NOTIFICATION_DELAY, TimeUnit.SECONDS)
.maximumSize(500)
.build(
new CacheLoader<>() {
@Override
public Notification load(@NonNull User user) {
return new Notification(null, 0);
}
}
);
/**
* Sends message to a user only if the message hasn't been sent recently
* @param user - user
* @param message - message to send (already translated)
* @return true if message sent successfully, false it it has been throttled
*/
public synchronized boolean notify(User user, String message) {
try {
Notification lastNotification = notificationCache.get(user);
long now = System.currentTimeMillis();
if (now >= lastNotification.time() + (NOTIFICATION_DELAY * 1000) || !message.equals(lastNotification.message())) {
notificationCache.put(user, new Notification(message, now));
user.sendRawMessage(message);
return true;
}
return false;
} catch (ExecutionException e) {
return false;
}
}
}