I would like to match:
some.name.separated.by.dotsBut I don't have any idea how.
I can match a single part like this
\w+\.How can I say "repeat that"
44 Answers
Try the following:
\w+(?:\.\w+)+The + after (?: ... ) tell it to match what is inside the parenthesis one or more times.
Note that \w only matches ASCII characters, so a word like café wouldn't be matches by \w+, let alone words/text containing Unicode.
EDIT
The difference between [...] and (?:...) is that [...] always matches a single character. It is called a "character set" or "character class". So, [abc] does not match the string "abc", but matches one of the characters a, b or c.
The fact that \w+[\.\w+]* also matches your string is because [\.\w+] matches a . or a character from \w, which is then repeated zero or more time by the * after it. But, \w+[\.\w+]* will therefor also match strings like aaaaa or aaa............
The (?:...) is, as I already mentioned, simply used to group characters (and possible repeat those groups).
More info on character sets:
More info on groups:
EDIT II
Here's an example in Java (seeing you post mostly Java answers):
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Main { public static void main(String[] args) { String text = "some.text.here only but not Some other " + "there some.name.separated.by.dots and.we are done!"; Pattern p = Pattern.compile("\\w+(?:\\.\\w+)+"); Matcher m = p.matcher(text); while(m.find()) { System.out.println(m.group()); } }
}which will produce:
some.text.here
some.name.separated.by.dots
and.weNote that m.group(0) and m.group() are equivalent: meaning "the entire match".
This will also work:
(\w+(\.|$))+You can use ? to match 0 or 1 of the preceeding parts, * to match 0 to any amount of the preceeding parts, and + to match at least one of the preceeding parts.
So (\w\.)? will match w. and a blank, (\w\.)* will match r.2.5.3.1.s.r.g.s. and a blank, and (\w\.)+ will match any of the above but not a blank.
If you want to match something like your example, you'll need to do (\w+\.)+, which means 'match at least one non whitespace, then a period, and match at least one of these'.
(\w+\.)+Apparently, the body has to be at least 30 characters. I hope this is enough.
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