Java regex return after first matched pattern

Question

I want to extract word after first 'from' in the following string-

"anti-CD24 from Chemicon, and anti-CD48 from Santa"

Right now, I am using -

"from\s+([^\s]+)"

But it is giving both results 'Chemicon' and 'Santa' instead of only 'Chemicon'.

how to extract out the first result? I am using if (m.find()) and it is giving both results instead of first one. — user1419742
– user1419742, Commented Jun 30, 2012 at 11:12

Francisco Spaeth · Accepted Answer · 2012-06-30 11:17:58Z

1

Maybe you could do something like this:

    Pattern p = Pattern.compile("from\\s+([^\\s]+)");
    Matcher m = p.matcher("anti-CD24 from Chemicon, and anti-CD48 from Santa");
    if (m.find()) {
        System.out.println(m.group(1));
    }

This would take just the first one. And maybe you could use this regular expression to avoid the comma for the first match (Chemicon,): from\\s+([a-zA-Z]+)

answered Jun 30, 2012 at 11:17

Francisco Spaeth

24k8 gold badges72 silver badges107 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

verisimilitude Over a year ago

Gosh! Was gonna type the very same code after I just implemented it in my Eclipse.. +1 for being faster than me lol

user1419742 Over a year ago

thanx, but i am using like anti-CD24.*from\\s+([^\\s]+), in which case it is actually matching the last one ie. 'Santa', but i want to extract 'Chemicon,'

quux00 · Accepted Answer · 2012-06-30 12:58:54Z

0

You can use the lookingAt method on the Method object. It stops after it finds the first match.

Like the matches function and unlike the find function lookingAt has to match from the beginning, so we have to use the regex ".*?from\\s+(\\w+)", which says: match anything up until the first "from", then one or more whitespace chars, then the next "word". If you only want alphabetical chars to match your word after "from" then use ".*?from\\s+([a-zA-Z])". The ".*?" at the beginning means non-greedy matching. If you just use ".*" it will match the last "from", not the first one.

Here's code that I've tested:

  String s = "anti-CD24 from Chemicon, and anti-CD48 from Santa";
  Matcher m = Pattern.compile(".*?from\\s+(\\w+)").matcher(s);
  if (m.lookingAt()) {
    System.out.println(m.group(1));
  }

Prints out:

Chemicon

answered Jun 30, 2012 at 12:58

quux00

14.8k12 gold badges59 silver badges72 bronze badges

2 Comments

user1419742 Over a year ago

thanx, it even worked with using find, after i used .*? instead of .*

quux00 Over a year ago

Yes, good catch - that also works in this case. Because we use non-greedy matching of any character that would make find work like lookingAt in this scenario.

Collectives™ on Stack Overflow

Java regex return after first matched pattern

2 Answers 2

2 Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related