#fixed code
                                public void remove(Guild guild) {
        this.guilds.remove(guild.getRank());

        Collections.sort(this.guilds);
    }
#vulnerable code 
                                public void remove(Guild guild) {
        this.guilds.remove(guild.getRank());

        synchronized (guilds) {
            Collections.sort(this.guilds);
        }

    } 
                            #location 2 
                            #vulnerability type THREAD_SAFETY_VIOLATION