Synchronization question

Hey Bukkit,

I have a question about synchronization.

Is it possible to use block synchronization to use non-threadsafe methods in asynchronously executed code.

For example:

Code:java

 
public void playerTest() { // Sync
 
    final Player player = Bukkit.getServer().getOnlinePlayers()[0];
 
    new BukkitRunnable() { // Async
        @Override
        public void run() {
 
        // Is this allowed?
        synchronized (Bukkit.getServer()) {
            player.sendMessage("Test");
        }
 
        // Is this allowed?
        synchronizedMethodCall(player);
 
        }
    }.runTaskAsynchronously(plugin);
}
 
public synchronized void synchronizedMethodCall(Player player) {
    player.sendMessage("test");
}
 

Would those two asynchronous accesses be allowed?

 

Prozza no, sadly enough you cannot synchronize external libraries like that since it doesn't synchronize access from third parties (other plugins, MC)

 

Your first example only suspends execution of other synchronized calls to the object returned by Bukkit#getServer(). So methods that aren't synchronized don't have to wait until the object's or class' lock has been released.

Your second one only acquires the lock of the object it is in, but not the lock of the Player object it invokes a method on. Other threads can still invoke Player#sendMessage(String) on that Player object at the exact same moment as you.

It is not possible to use synchronized to block access to non-synchronized methods.