text: public String toString() {if (isEmpty()) {return "[]";}StringBuilder buffer = new StringBuilder(size() * 16);buffer.append('[');Iterator<?> it = iterator();while (it.hasNext()) {Object next = it.next();if (next != this) {buffer.append(next);} else {buffer.append("(this Collection)");}if (it.hasNext()) {buffer.append(", ");}}buffer.append(']');return buffer.toString();}