Re: empty interfaces via reflection

From:

Steven Simpson <ss@domain.invalid>

Newsgroups:

comp.lang.java.programmer

Date:

Fri, 19 Oct 2007 17:14:43 +0100

Message-ID:

<YbqdnX-9mfqeRYXaRVnyugA@pipex.net>

Aryeh M. Friedman wrote:

the
following test code (using findClass not loadClass as the override
method) still doesn't work:

public static void main(String[] args)
                throws Throwable
        {
                while(true) {
                        ClassLoader loader=new MyClassLoader();

I did get the following to work. It uses a URLClassLoader, as Daniel
Pitts suggested. Your MyClassLoader didn't seem to be doing anything
extra, so you may as well use the existing class - though I don't see
why yours wouldn't work.

You give the directory containing the class to be tested as the first
argument, and it is turned into a URL for the class loader. Make sure
this directory is not in your classpath.

import java.io.*;
import java.net.*;

public class Test {
  public static void main(String[] args) throws Throwable {
    File f = new File(args[0]);
    URL[] path = new URL[] { f.toURI().toURL() };

    while (true) {
      ClassLoader loader = new URLClassLoader(path);
      Class klass = loader.loadClass("SomeClass");
      Object o = klass.newInstance();

      System.out.println(o.getClass().getDeclaredMethod("getAck").
                         invoke(o));
      System.in.read();
    }
  }
}

--
ss at comp dot lancs dot ac dot uk |