https://github.com/Bukkit/Bukkit

https://github.com/Bukkit/CraftBukkit

http://forum.minecraftuser.jp/viewtopic.php?f=7&t=22679

MinecraftServer.java
<code java>
                    if (this.worlds.get(0).everyoneDeeplySleeping()) { // CraftBukkit
                        this.q();
                        j = 0L;
                    } else {
                        while (j > 1L) {
                            MinecraftServer.currentTick = (int) (System.currentTimeMillis() / 1); // CraftBukkit
                            j -= 1L;
                            this.q();
                        }
                    }

                    Thread.sleep(1L);
                }
</code>

PendingConnection.java => LoginListener
<code java>
    public void c() {
        if (this.h) {
            this.d();
        }

        if (this.f++ == 60000) {
            this.disconnect("Took too long to log in");
        } else {
            this.networkManager.b();
        }
    }
</code>