How to delete all the characters after one character in the String?

Question

I have a String which contains a date, for example "01-01-2012", then an space and then the time "01:01:01". The complete string is: "01-01-2012 01:01:01"

I would like to extract only the date from this string so at the end I would have "01-01-2012" but don't know how to do this.

Answer 1

Four options (last two added to make this one answer include the options given by others):

• Parse the whole thing as a date/time and then just take the date part (Joda Time or SimpleDateFormat)

• Find the first space using indexOf and get the leading substring using substring:

  int spaceIndex = text.indexOf(" ");
  if (spaceIndex != -1)
  {
      text = text.substring(0, spaceIndex);
  }
  

• Trust that it's valid in the specified format, and that the first space will always be at index 10:

  text = text.substring(0, 10);
  

• Split the string by spaces and then take the first result (seems needlessly inefficient to me, but it'll work...)

  text = text.split(" ")[0];
  

You should consider what you want to happen if there isn't a space, too. Does that mean the data was invalid to start with? Should you just continue with the whole string? It will depend on your situation.

Personally I would probably go with the first option - do you really want to parse "01-01-2012 wibble-wobble bad data" as if it were a valid date/time?