code: public static boolean isDouble(String number) {
          boolean result = false;
          if (number != null) {
              try {
                  Double.parseDouble(number);
                  result = true;
              } catch (NumberFormatException e) {
              }
          }
          return result;
      }
docs: Checks if a string is a valid Double
  
  @param number The string to check.
  @return True if the string is a valid double else false.