code: void removeComputer(final Computer computer) {
          Queue.withLock(new Runnable() {
              @Override
              public void run() {
                  Map<Node,Computer> computers = getComputerMap();
                  for (Map.Entry<Node, Computer> e : computers.entrySet()) {
                      if (e.getValue() == computer) {
                          computers.remove(e.getKey());
                          computer.onRemoved();
                          return;
                      }
                  }
              }
          });
      }
docs: /*package