Regex for broken links with whitespaces

Question

i am using this Regex

private static final String HREF_PATTERN = 
    "\\s*(?i)href\\s*=\\s*(\"([^\"]*\")|'[^']*'|([^'\">\\s]+))";

to get the link from

 <a href=www.example.com/1234 5678>

The URL is malformed. It contains a whitespace. The Problem is that i want to get the whole link including "5678", but i only get "www.example.com/1234".

I am not that good with regular Expressions. Can someone please provide a valid regex so that i can get the whole url "www.example.com/1234 5678".

Thanks

Why would a URL contain whitespace? Usually spaces are converted to `%20` — Arc676, Oct 21 '15 at 12:44
The URL is being created from another program which i am not able to edit — gRds, Oct 21 '15 at 12:46
Replace the withespaces with %20 then and keep your regex for valid urls — Nitek, Oct 21 '15 at 12:50
can't you provide the url inside the quotes and just get it from within? — Stanislav, Oct 21 '15 at 12:57
Thats part of the Problem. The link is not within quotes. If it where within quotes the problem wouldn`t even exist. The external program creates an html Email with several tags. Replacing all Whitespaces is also not an option, because this would also remove all whitespaces from the email-text — gRds, Oct 21 '15 at 13:02
Try `"\\s*(?i)href\\s*=\\s*(\"([^\"]*\")|'[^']*'|([^'\">]+))"`. Unless your `` tags contain other attributes, this will capture the whole href value. Or, you can just use a look-ahead to stop before the next attribute name: `(?i)\\s*href\\s*=\\s*(\"([^\"]*\")|'[^']*'|([^'\">]+(?=\\s+\\w+=|>)))` — Wiktor Stribiżew, Oct 21 '15 at 13:06

score 2 · Accepted Answer · answered Oct 21 '15 at 13:24

The external program creates an html Email with several <a href=www.example.com/1234 5678> tags.

Assuming you cannot fix it on the source level, you can try fixing that with a regex.

If the href attribute is the only attribute, you just do not have to care about the spaces after =. Remove \\s from your pattern and it will work.

private static final String HREF_PATTERN = 
   "(?i)\\s*href\\s*=\\s*(\"([^\"]*\")|'[^']*'|([^'\">]+))";
                                                     ^

If you have attributes with values, you will have to use a look-ahead:

private static final String HREF_PATTERN = 
    (?i)\\s*href\\s*=\\s*(\"([^\"]*\")|'[^']*'|([^'\">]+(?=>|\\s+\\w+=)))

See the regex demo

However, this will not work with attributes like nofollow.

Regex for broken links with whitespaces

1 Answers1