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Thread: java ip regex

  1. #1
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    Default java ip regex

    hi i have this regex that finds ip and port ie.121.121.121.121:0000; in a string

    "\\d{1,3}(?:\\.\\d{1,3}){3}(?::\\d{1,5})?"

    the problem is if the port is missing this regex still finds just the ip which i dont want i want it to be all or nothing ip:port i tought removing the ? at the very end should achieve this but i still have the same problem.
    does anyone know how or direct me to the information i need to chainge this to only identifing ip and port.
    thanks.


  2. #2
    Member Chris.Brown.SPE's Avatar
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    Default Re: java ip regex

    Yes, your problem is the question mark. In a regular expression, the "?" means "Zero or 1 times". In your case of not having the ":0000" on the end would qualify for "Zero times". You were correct to remove the "?" and that should have worked. Could you post a set of code that i could test and see the issue occurring? A workaround may be to put a "{1}". It seems to me like you have an issue that is not just in the regex string.
    Writing code is your job, helping you fix and understand it is mine.

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    Default Re: java ip regex

    thanks it was a problem elsewhere in code thanks

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