Can anyone tell me what are the invalid characters for HTTP URL and the best way to validate the same in Java. What I am looking for is URLString validation in t开发者_C百科he URL format: http(s)://ip:port/URLString

Thanks in advance.

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You can use any unicode characters you want, as long as they are % encoded. The explicitly reserved characters are defined in section 2.2 of RFC3986: https://www.rfc-editor.org/rfc/rfc3986#section-2

From the document:

  reserved    = gen-delims / sub-delims

  gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"

  sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
              / "*" / "+" / "," / ";" / "="

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According to RFC 1738 the following are deemed unsafe:

1. < and > - delimiters around URLs in free text
2. " (double quote) - delimits URLs in some systems

3. - delimits a URL from a fragment/anchor identifier that might follow it

4. % - used to indicate character encodings

General unsafe characters: { } | \ ^ ~ [ ] `

Edit:

Not a duplicate, but includes some thoughts on validation in Java: Validate URL in java

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Read RFC1738 Page 2 and Page 3 on the link for details.

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How about using UrlValidator ? isValidPath method probably useful. :)