JAVA regex failing

Question

I have string which is of format:

;1=2011-10-23T16:16:53+0530;2=2011-10-23T16:16:53+0530;3=2011-10-23T16:16:53+0530;4=2011-10-23T16:16:53+0530;

I have written following code to find string 2011-10-23T16:16:53+0530 from (;1=2011-10-23T16:16:53+0530;)

Pattern pattern = Pattern.compile("(;1+)=(\\w+);");

String strFound= "";
Matcher matcher = pattern.matcher(strindData);
while (matcher.find()) {
   strFound= matcher.group(2);
}

But it is not working as expected. Can you please give me any hint?

score 4 · Answer 1 · answered Feb 05 '12 at 14:05

4

Can you please give me any hint?

Yes. Neither -, nor :, nor + are part of \w.

answered Feb 05 '12 at 14:05

Tomalak

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score 3 · Answer 2 · edited May 23 '17 at 11:48

Do you have to use a regex? Why not call String.split() to break up the string on semi-colon boundaries. Then call it again to break up the chunks by the equals sign. At that point you'll have an integer and the date in string form. From there you can parse the date string.

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public final class DateScan {
    private static final String INPUT = ";1=2011-10-23T16:16:53+0530;2=2011-10-23T16:16:53+0530;3=2011-10-23T16:16:53+0530;4=2011-10-23T16:16:53+0530;";
    public static void main(final String... args) {
        final SimpleDateFormat parser = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");
        final String[] pairs = INPUT.split(";");
        for (final String pair : pairs) {
            if ("".equals(pair)) {
                continue;
            }
            final String[] integerAndDate = pair.split("=");
            final Integer integer = Integer.parseInt(integerAndDate[0]);
            final String dateString = integerAndDate[1];
            try {
                final Date date = parser.parse(dateString);
                System.out.println(integer + " -> " + date);
            } catch (final ParseException pe) {
                System.err.println("bad date: " + dateString + ": " + pe);
            }
        }
    }
}

score 1 · Accepted Answer · answered Feb 05 '12 at 14:36

I've change the input a bit, but just for presentation reasons that is

You can try this:

 String input = " ;1=2011-10-23T16:16:53+0530;   2=2011-10-23T16:17:53+0530;3=2011-10-23T16:18:53+0530;4=2011-10-23T16:19:53+0530;";

Pattern p = Pattern.compile("(;\\d+?)?=(.+?);");
Matcher m = p.matcher(input);

while(m.find()){
    System.out.println(m.group(2));
}

JAVA regex failing

3 Answers3