Empty Strings

It is possible for two delimiters to occur with nothing between them. For example

String manyAnimals = "ant ,  ,  cat,   dog" ;

String[] pieces = manyAnimals.split( " *, *");

produces the array

String[] pieces = {"ant", "", "cat", "dog"};

The RE matches two substrings between ant and cat, leaving no unmatched characters, so the item that goes into the array is a reference to an empty string. (Note that this is a String object that contains no characters, not the value null.)

Also note that the white space at the beginning and end of a string may be included in an item the string has been split into. The following fragment

String manyPets = "  ant   ,    bat   ,   cat   " ;

String[] pieces = manyAnimals.split( " *, *");

creates the array

String[] pieces = {"  ant" , "bat", "cat   "};