I have nearly no knowledge about class loaders and nearly no
 experience with tem, but recently I hacked together something
 like this. - Not exactly the same as you require: It does
 not use two names, but two class loaders.

 Beware! The following example does not follow style rules for
 writing good class loaders!

 I wanted to show how to create two "instances" of a class with
 static entries:

public class Scan { static int i = 0; public static int get(){ return i++; }}

 So here I go, creating two "instances":

public class Main
{ public static void main( java.lang.String[] args ) throws java.lang.Exception
 { final java.lang.Class instance1 = new ScanLoader().loadClass( "Scan" );
   final java.lang.Class instance2 = new ScanLoader().loadClass( "Scan" );
   final java.lang.Class[] c = new java.lang.Class[]{};
   final java.lang.Object[] o = new java.lang.Object[]{};
   java.lang.System.out.println( instance1.getMethod( "get", c ).invoke( null, o ));
   java.lang.System.out.println( instance1.getMethod( "get", c ).invoke( null, o ));
   java.lang.System.out.println( instance2.getMethod( "get", c ).invoke( null, o ));
   java.lang.System.out.println( instance2.getMethod( "get", c ).invoke( null, o )); }}

 They can count indepently of each other, as the
 output shows:

0
1
0
1

 And here is my custom class loader hack:

class ScanLoader extends ClassLoader
{ public ScanLoader()
 { super( ScanLoader.class.getClassLoader() ); }
 public java.lang.Class<?> loadClass( final java.lang.String className )
 throws ClassNotFoundException
 { return findClass( className ); }
 public java.lang.Class<?> findClass( final java.lang.String className )
 { byte classByte[];
   java.lang.Class<?> result = null;
   if( "java.lang.Object".equals( className ))return java.lang.Object.class;
   try
   { java.lang.String classPath =
     (( java.lang.String )ClassLoader.getSystemResource
     ( className.replace( '.', java.io.File.separatorChar ) + ".class" ).getFile() ).
     substring( 1 );
     classByte = loadClassData( classPath );
     result = defineClass( className, classByte, 0, classByte.length, null );
     return result; }
   catch( final java.lang.Exception e ){ throw new java.lang.RuntimeException(e); }}
 private byte[] loadClassData
 ( final java.lang.String className )
 throws java.io.IOException
 { final java.io.File f = new java.io.File( className );
   final int size =( int )f.length();
   final byte buff[] = new byte[ size ];
   { java.io.FileInputStream fis = new java.io.FileInputStream( f );
     { java.io.DataInputStream dis = new java.io.DataInputStream( fis );
       dis.readFully( buff );
       dis.close(); }}
   return buff; }}

On Fri, 13 Jan 2006 17:46:01 +0100, Francesco Devittori
<frenkatfrenkdtcm> wrote, quoted or indirectly quoted someone who said

Yes. Your problem is you must also modify the jvm byte codes because
the class name is also embedded in there.  See
http://mindprod.com/jgloss/classloader.html
and http://mindprod.com/jgloss/jasm.html

IIRC the JVM will not allow you to load a class under any name except that
which is embedded in the classfile definition.  Therefore you would have to
decode and re-encode the classfile (not impossible, not even all that
difficult, but you'll need something like the ASM library or BCEL).

   -- chris