How come

http:/server.host.com is accepted by:
new URL (String)
without causing an exception

but 

ftp:/server.host.com is not?

Of course neither should be - or am I doing something really stupid here 


Simon
(Review ID: 32279)
======================================================================




/*
The following URL fails to generate a MalformedURLException:

  http:/java.sun.com

Furthermore, the following URL gets "fixed" to the one above, 
which is still wrong:

  http:java.sun.com

Although this bug is presumably cross platform, I only attempted 
to reproduce it under Windows 98.

*/

import java.net.*;

public class UrlBug
{
  public static void main(String[] args)
  {
    URL theUrl;
    String src="";
    try
    {
      src = "http:java.sun.com";
      theUrl = new URL(src);
      System.out.println("URL 1 -- <" + theUrl + ">");

      src = "http:/java.sun.com";
      theUrl = new URL(src);
      System.out.println("URL 2 -- <" + theUrl + ">");

      System.out.println("\nNo MalformedURLException detected");
    }
    catch (MalformedURLException ex)
    {
      System.out.println("Bad URL: " + src);
    }
  }
}
(Review ID: 83633)
======================================================================
Posted Date : 2006-12-07 15:09:15.0

N/A

The URL http:/server.host.com has no host part, so the URL it creates has
no host, it points to the file "http://localhost/server.host.com"
  xxxxx@xxxxx   1998-05-27

  xxxxx@xxxxx   2000-03-09

In order to fix this bug, we must enhance the method parseURL() in
URLStreamHandler to throw the MalformedURLException. This enhancement 
is described in an RFE (reference #4273176) and is commited to the
Tiger release of the J2SE. 

I have commited this bug to Tiger and added RFE #4273176 to the
seeAlso field.


  xxxxx@xxxxx   2003-07-09

Decommit from Tiger due to dependencies on RFE #4273176.
Associated RFE will not be implemented due to compatibility issues. See 4273176 for details.
Therefore closing as will not fix.
Posted Date : 2006-12-07 15:09:15.0

Also a URL such as "http://java. sun.com/" is accepted. Should spaces
be allowed? Perhaps there should be a method
String getURLWarning() (or somrthing similar)
which would return a message such as
"Your URL contains spaces. This may cause a problem"
"You have not specified a domain name. This may cause a problem outside
your network"
"You did not specify a protocol. Http:// was assumed"
This would allow a developer to create a URL which would be syntactically
accepted, but
the text in getURLWarning() would be displayed to the user to report any
potential 
problems without actually raising an exception.
A checkURLValid() which goes out to see if the page is actually exists or is
not found,
would be nice too!