StringTokenizer class

[Puspender Tanwar]

# Code from Enthuware mocks exams #

StringTokenizer st = new StringTokenizer("a aa aaa", "x");
while (st.hasMoreTokens()) {
System.out.println(st.nextToken());

outputs : a aa aaa
because there is no "x" in the string so no match found and a single token is returned (original string)

but when i make changes to above code by putting a space before delimiter :

StringTokenizer st = new StringTokenizer("a aa aaa", " x"); // space before x
while (st.hasMoreTokens()) {
System.out.println(st.nextToken());

as i can see, here also the delimiter we specify should not match in the string as there is not any " x" in the string, then why is output :
a
aa
aaa

In the same way, why

StringTokenizer st = new StringTokenizer("a aa aaa", " a"); // space before a

returns zero token
but

StringTokenizer st = new StringTokenizer("a aa aaa", "a");

returns one token ( a empty string ) ?

[Jeanne Boyarsky]

Puspender,
The StringTokenizer API is tricky. Each character in the delimiters are characters not a sequence. That means " x" splits on spaces OR x. That's why you get the three tokens - there are there are two spaces so three portions.

For the second example " a" splits on spaces or a. Which is all the characters.

[Puspender Tanwar]

Thanks Jeanne