" ".split(" ") generates a NullPointerException : String Split « Data Type « Java Tutorial

public class Main {
  public static void main(String args[]) throws Exception {

    String[] words = " ".split(" ");
    String firstWord = words[0];

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
  at Main.main(Main.java:5)

2.32.String Split
2.32.1.Split string
2.32.2.Split a String
2.32.3.Using split() with a space can be a problem
2.32.4." ".split(" ") generates a NullPointerException
2.32.5.String.split() is based on regular expression
2.32.6.String split on multicharacter delimiter
2.32.7.Split by dot
2.32.8.Split up a string into multiple strings based on a delimiter
2.32.9.Splits a string around matches of the given delimiter character.
2.32.10.Splits the provided text into an array, separator string specified. Returns a maximum of max substrings.
2.32.11.Splits the provided text into an array, using whitespace as the separator, preserving all tokens, including empty tokens created by adjacent separators.