Splitting strings based on a delimiter

Question

I am trying to break apart a very simple collection of strings that come in the forms of

0|0
10|15
30|55

etc etc. Essentially numbers that are seperated by pipes.

When I use java's string split function with .split("|"). I get somewhat unpredictable results. white space in the first slot, sometimes the number itself isn't where I thought it should be.

Can anybody please help and give me advice on how I can use a reg exp to keep ONLY the integers?

I was asked to give the code trying to do the actual split. So allow me to do that in hopes to clarify further my problem :)

String temp = "0|0";
String splitString = temp.split("|");

results

\n
0
| 
0

I am trying to get

0
0

only. Forever grateful for any help ahead of time :)

Answer 1

I still suggest to use split(), it skips null tokens by default. you want to get rid of non numeric characters in the string and only keep pipes and numbers, then you can easily use split() to get what you want. or you can pass multiple delimiters to split (in form of regex) and this should work:

String[] splited = yourString.split("[\\|\\s]+");

and the regex:

import java.util.regex.*;

Pattern pattern = Pattern.compile("\\d+(?=([\\|\\s\\r\\n]))");
Matcher matcher = pattern.matcher(yourString);
while (matcher.find()) {
    System.out.println(matcher.group());
}

Answer 2

The pipe symbol is special in a regexp (it marks alternatives), you need to escape it. Depending on the java version you are using this could well explain your unpredictable results.

class t {
    public static void main(String[]_)
    {
        String temp = "0|0";
        String[] splitString = temp.split("\\|");

        for (int i=0; i<splitString.length; i++)
            System.out.println("splitString["+i+"] is " + splitString[i]);
    }       
}

outputs

splitString[0] is 0
splitString[1] is 0

Note that one backslash is the regexp escape character, but because a backslash is also the escape character in java source you need two of them to push the backslash into the regexp.