Name: mc57594 Date: 11/04/99

Attempting to use an FTP URL in a URLClassLoader with username:password syntax *appears* to be broken; example (username and password changed to protect the innocent :) ):

import java.net.URL;
import java.net.URLClassLoader;

import java.io.*;

public class FTPURLClient
{
    /**
     * Attempt to instantiate an instance of the class
     * com.javageeks.util.Hello, found only on the javageeks.com
     * FTP server in the "examples" directory.
     */
    public static void main(String[] args)
        throws Exception
    {
        URL[] urlArray =
        {
            new URL("ftp", "reader:###@###.###",
                    "/examples/")
        };

        URLClassLoader ucl = new URLClassLoader(urlArray);
        Object obj =
            ucl.loadClass("Hello").newInstance();
            
        // Hello should print "Hello from JavaGeeks.com!" to the
        // System.out stream
    }
}

Instead, the output is:

E:\Projects\Books\SSJ\cd\Src\Chap02>java FTPURLClient
Exception in thread "main" java.lang.ClassNotFoundException: Hello
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:191)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:280)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:237)
        at FTPURLClient.main(FTPURLClient.java:24)

If a trailing "/" is appended to "/examples" in the file portion of the URL (examples is a directory which contains the Hello.class file), the output is:

E:\Projects\Books\SSJ\cd\Src\Chap02>java FTPURLClient
Exception in thread "main" java.lang.IllegalArgumentException: invalid port rang
e: ###@###.###
        at java.net.SocketPermission.init(SocketPermission.java:338)
        at java.net.SocketPermission.<init>(SocketPermission.java:206)
        at java.net.URLClassLoader.getPermissions(URLClassLoader.java:417)
        at java.security.SecureClassLoader.getProtectionDomain(SecureClassLoader
.java:145)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:10
1)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:248)
        at java.net.URLClassLoader.access$1(URLClassLoader.java:216)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:191)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:280)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:237)
        at FTPURLClient.main(FTPURLClient.java:24)
(Review ID: 84958)
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From: chamness <###@###.###>
To: ###@###.### <###@###.###>
Date: Tuesday, June 29, 1999 8:07 PM
Subject: Re: (Review ID: 84958) FTP URLs in URLClassLoader appear to be
broken

>Ted,
>Before we start debugging the problem, can you try something?
>It looks like you want to load the class, com.javageeks.util.Hello.
>But in your application you wrote:
> ucl.loadClass("Hello").newInstance();
>
>Can you try:
> ucl.loadClass("com.javageeks.util.Hello").newInstance();
>I assume that you have the class Hello in the appropriate
>subdirectory.
>
>Mark
========================================
From: "Ted Neward" <###@###.###>
To: "chamness"
Subject: Re: (Review ID: 84958) FTP URLs in URLClassLoader appear to be broken
Date: Tue, 29 Jun 1999 23:21:59 -0700

Actually, I've tried both approaches; I shortened it to just "Hello" in
order to eliminate the possibility that the FTP-URLClassLoader thing didn't
handle package-names-as-directories well. The code actually comes from a
chapter I'm writing on ClassLoaders for a book that's coming out soon. The
original intent was to download the fully package-qualified verison of
Hello, but now I'll settle for a plain 'ol unnamed-package version. :)

I've got two FTP servers I've tested this approach against--an NT4.0/IIS FTP
web server, and a Linux RedHat 5.2 FTP server, both as anonymous and using
the username-password approach. I freely admit I'm not a system admin, but
I'm pretty sure I got the FTP parts right--I can FTP in using the userid and
password using ye olde standard FTP command.

Anything else I can offer to help?

Ted Neward
Patterns/C++/Java/CORBA/EJB/COM-DCOM spoken here
http://www.javageeks.com/~tneward
 "I don't even speak for myself; my wife won't let me." --Me


Name: krC82822 Date: 12/19/2000


orig synopsis: "URL doesn't support the same syntax with ftp and http"

java version "1.3.0"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0-C)
Java HotSpot(TM) Client VM (build 1.3.0-C, mixed mode)

Since version 1.2, java.net.URL has supported the following syntax:

ftp://username:password@host/path/file

but not:

http://username:password@host/path/file

It would be nice, if version 1.4 would support this syntax for
both ftp and http.
(Review ID: 110326)
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