Java URL counter is not working

Question

I'm trying to count the number of URLs in any given Java string:

String test = "Hello World!";
String urlRegex = "<\\b(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]>";
pattern = Pattern.compile(urlRegex);
matcher = pattern.matcher(test);
numUrls = matcher.groupCount();
System.err.println("numUrls = " + numUrls);

I am surprised to see that numUrls is not zero. Any ideas as to why? Thanks in advance!

You need to use matcher.find(), there's always one group.

Boris the Spider
– Boris the Spider

2013-03-19 18:33:44 +00:00
Commented Mar 19, 2013 at 18:33 — Boris the Spider
– Boris the Spider, Commented Mar 19, 2013 at 18:33
What if there are 6 URLs in the string?

IAmYourFaja
– IAmYourFaja

2013-03-19 18:36:22 +00:00
Commented Mar 19, 2013 at 18:36 — IAmYourFaja
– IAmYourFaja, Commented Mar 19, 2013 at 18:36

Community · Accepted Answer · 2020-06-20 09:12:55Z

0

From the javadoc for Matcher#groupCount()

Returns the number of capturing groups in this matcher's pattern.

Your pattern has one group ...(https?|ftp|file)... so it returns 1.

edited Jun 20, 2020 at 9:12

CommunityBot

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answered Mar 19, 2013 at 18:35

Sotirios Delimanolis

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4 Comments

IAmYourFaja Over a year ago

Hmmm good catch and +1 - so what do I need to use instead of groupCount?

IAmYourFaja Over a year ago

Im trying to count the number of URLs in a Java string.

Sotirios Delimanolis Over a year ago

Loop on find() and use your own counter.

IAmYourFaja Over a year ago

So like while(matcher.find()) numUrls++;?

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