Java: String and using the split function?

Question

OK, Im trying to split a string containing an IP Address into the 4 byte address.
Here is my code:

getIP(String st){ //st contains "192.168.1.21"
String[] var = st.split(".");
...

After the split, var has a length of 0. WHY???

If I change it to:
String[] var = st.split("1");
...
I get what I would expect with var having a length of 4 and each string containing:
var[0] = ""
var[1] = "92."
var[2] = "68."
var[3] = ".2"

Can you not use the dot (.) character to split a string???

larrybud2004 · Accepted Answer

Split works fine, but it's expecting a regular expression.  Since the "." in RegEx is a special character, you have to escape it.

BUT since "&#92;" has a special meaning in a string, you have to escape it TOO  SO

String[] var = st.split("&#92;&#92;.");

Anonyme · Answer

Split Function In Java

Sadsongs · Answer

I've never used split (it's a while since I wrote any Java) but as it takes a regexp, you'd have to escape the . I would say.

Java: String and using the split function?

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