ShutdownDetector.java

package ninja.smirking.demo.shutdown;

import org.bukkit.plugin.java.JavaPlugin;

import java.util.logging.Level;
import java.util.regex.Pattern;

/**
 * @author Connor Spencer Harries
 */
public class ShutdownDetector extends JavaPlugin {
    private static final Pattern SERVER_CLASS_PATTERN = Pattern.compile("net\.minecraft\.server\.v[0-9]_[0-9]_R[0-9]\.MinecraftServer");

    @Override
    public void onDisable() {
        StackTraceElement[] elements = Thread.currentThread().getStackTrace();
        if(elements.length >= 7) {
            StackTraceElement element = elements[7];
            if(element.getMethodName().equals("stop") && SERVER_CLASS_PATTERN.matcher(element.getClassName()).matches()) {
                getLogger().log(Level.INFO, "Bukkit is shutting down.");
                return;
            }
        }
        getLogger().log(Level.INFO, "Bukkit isn't shutting down.");
    }
}