Re: Silly URL...

On Wed, 27 Jul 2005 20:38:33 -0600, Chris Smith wrote:

> So I'm pretty sure you don't need a URL. However, if you do, then the
> best way to go is to get a File object first, and then say:
>
> File file; // the file object you start with
> URL url = file.toURI().toURL();
>
> Then yes, you are perfectly fine using the URL to refer to files on the
> local disk. This is actually guaranteed to work, as all Java virtual
> machines are required to support the URL scheme for accessing local
> files. However, since the exact syntax is platform-specific, the
> conversion methods above are your best bet here.

I don't agree.

Because of my long experience with applets, I have come to loath
using File's for *reading* resources, except where absolutely necessary.

Note that while an URL can refer to a local File..

- A File cannot pull a resources.jar!/README.txt straight out of
the archive, while a (jar) URL can.

- A File cannot refer to a resource on an http site, or ftp, or..

About all I uses File's for is when I am working on the local system
in a fully trusted applet or application and need a
File.listFiles()/File.listFiles(FileFilter), or File.listRoots().
[ Oh, and all that *O* of I/O. ]

As a further note, you mention the "exact syntax is platform-specific"
as a downside. But how many times have you seen code similar to this?

File props = new File("resources\\properties.xml");

...use of File's can easily be made 'platform specific', purely by accident.

As far as getting a handle on the resource, I would recommend an
alternate route (where practical*).

Class.getResource() - removes the platform specific parts from needing
any programmer intervention, the rest is handled automatically (which
is good, since I have a devil of a time remembering the format of
those 'jar file' URL's!).

* Which it is not, if the resource is not on the classpath!

In any case, if I offer the end user a 'File' chooser, the returned File
will (generally) be converted to an URL within the next few code lines..

--
Andrew Thompson
physci.org 1point1c.org javasaver.com lensescapes.com athompson.info
Not Affiliated With Futurama Brass Knuckle Co.
.

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