Name: akC57697 Date: 09/23/98



  The java.net.URL c-tor does not throw MalformedURLException on
  incorrect FILE: requests which use "diskname:" in path.


The doc of Network Working Group
Request for Comments: 1630 CERN
Category - Informational June 1994


                 Universal Resource Identifiers in WWW

                A Unifying Syntax for the Expression of
             Names and Addresses of Objects on the Network
                     as used in the World-Wide Web"
says:
file

   The other URI schemes (except nntp) share the property that they are
   equally valid at any geographical place.

   There is however a real practical requirement to be able to generate
   a URL for an object in a machine's local file system.

   The syntax is similar to the ftp syntax, but in this case the slash
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   is used to donate boundaries between directory levels of a
   hierarchical file system is used. The "client" software converts the
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   file URL into a file name in the local file name conventions. This
   allows local files to be treated just as network objects without any
   necessity to use a network server for access. This may be used for
   example for defining a user's "home" document in WWW.

   There is clearly a danger of confusion that a link made to a local
   file should be followed by someone on a different system, with
   unexpected and possibly harmful results. Therefore, the convention
   is that even a "file" URL is provided with a host part. This allows
   a client on another system to know that it cannot access the file
   system, or perhaps to use some other local mecahnism to access the
   file.

   The special value "localhost" is used in the host field to indicate
   that the filename should really be used on whatever host one is.
   This for example allows links to be made to files which are
   distribted on many machines, or to "your unix local password file"
   subject of course to consistency across the users of the data.

   A void host field is equivalent to "localhost".
"


The javadoc:
"
More information on the types
of URLs and their formats can be found at:
          http://www.ncsa.uiuc.edu/demoweb/url-primer.html
(see above)
..........
public URL(String spec)
    throws MalformedURLException

     Creates a URL object from the String representation.

     This constructor is equivalent to a call to the two-argument constructor with
     a null first argument.
     Parameters:
         spec - the String to parse as a URL.
     Throws:
         MalformedURLException - If the string specifies an unknown protocol.
"

The example:
--------------------------------8-<---------------------------
class Test {
  public static void main(String[] argv) {
  
    try {
     java.net.URL u = new java.net.URL("file:C:/autoexec.bat");
                                     // Should be "file:///C:/autoexec.bat"
     System.out.println("No MalformedURLException");
    } catch (java.net.MalformedURLException e) {
      System.out.println("OKAY");
      return;
    }
  }
}

--------------------------------8-<---------------------------
java full version "JDK-1.2fcs-K"
Output:
No MalformedURLException

   
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