if (str == null) str = "null"; int len = str.count; ensureCapacity_unsynchronized(count + len); str.getChars(0, len, value, count); count += len; return this;
return append(obj == null ? "null" : obj.toString());
  public synchronized StringBuffer append(String str)  {    if (str == null)      str = "null";    int len = str.count;    ensureCapacity_unsynchronized(count + len);    str.getChars(0, len, value, count);    count += len;    return this;  }