I have a Java application which streams Twitter data.
Assuming that I have a String text = tweet.getText() variable.
In a text we can have one or more @MentionedUser. I'd like to delete not just the @ but the username too.
How can I do this with replaceAll and without touching the rest of the string?
Thank you.
I would like to use (^|\s)@\w+($|\s) because you can get emails in your input like :
a @twitter username and a [email protected] another @twitterUserName
So you can use :
String text = "a @twitter username and a [email protected] another @twitterUserName";
text = text.replaceAll("(^|\\s)@\\w+($|\\s)", "$1$2");
// Output : a username and a [email protected] another
Details :
(^|\s) which match ^ start of string or | a space \s @\w+ match @ followed by one or more word characters which is equivalent to [A-Za-z0-9_]($|\s) which match $ end of string or | a space \sIf you want to go deeper to specify the correct syntax of twitter usernames i read this article here they mention some helpful information :
Your username cannot be longer than
15 characters. Your name can be longer (50 characters), but usernames are kept shorter for the sake of ease.A username can only contain alphanumeric characters (letters
A-Z, numbers0-9) with the exception of underscores, as noted above. ...
From this rules you use this regex as well :
(?i)(^|\s)@[a-z0-9_]{1,15}($|\s)
Here is an alternative which does not produce doubled whitespaces and also does not capture emails:
String str = "a @twitter @user username and a [email protected] another @twitterUserName @test [email protected]";
System.out.println(str.replaceAll("(?<=[^\\w])@[^@\\s]+(\\s+|$)", ""));
Output:
a username and a [email protected] another [email protected]
Explanation of the parts of the actual regex expression (?<=[^\w])@[^@\s]+(\s+|$) :
text = text.replaceAll("@\\w+", "");.\wmeans word characters,+means a greedy quantifier matching 1 or more. Documentation.