Re: Class.forName(...) on Windows

[Andrew Haley <aph at redhat dot com>]

Marco Trudel writes:

 > Because reflection is broken on windows, gcj is practically useless for 
 > real applications. So I'm looking into it. Unfortunately I'm stuck with 
 > a problem.
 > 
 > In the file natClassLoader.cc, method "jclass _Jv_FindClass 
 > (_Jv_Utf8Const *name, java::lang::ClassLoader *loader)", 
 > findLoadedClass(...) is called. Where is this method? I can't find it...
 > On linux, this returns the class but on windows, this will fail...
 > 
 > Some differences I noticed while debugging (maybe someone has an idea 
 > what could be the source of the problem):
 > - It seems class.forName() works at least partially. When starting an 
 > application, class.forName("gnu.gcj.convert.Output_8859_1") is 
 > internally called multiple times and this works.
 > On linux, class.forName("gnu.gcj.convert.Output_UTF8") is called.
 > - I used this to be able to print the className:
 > 	jsize length = _Jv_GetStringUTFLength (className);
 > 	char buffer[length];
 > 	_Jv_GetStringUTFRegion(className, 0, className->length(), buffer);
 > 	printf("\n### loading class %s ###\n", buffer);
 > On linux, this will output the correct classnames. On windows, there's 
 > rubbish at the end of it (e.g. "Hello1°" instead of "Hello1"). I assume 
 > that's because I didn't finish the buffer with a \0. It could be that 
 > the final step to get the class has the same mistake; so it will work on 
 > linux but don't on windows (slight chance, but who knows...).
 > - Searching for an own Class that is compiled into the executable has a 
 > difference between linux and windows. On linux, this won't return a 
 > classloader (natClass.cc, method forName()):
 > 	jclass caller = _Jv_StackTrace::GetCallingClass (&Class::class$);
 > 	if(caller) loader = caller->getClassLoaderInternal();
 > On windows, it will.
 > - The big difference seems to be that linux works with UTF-8, Windows 
 > with iso-8859-1. I haven't compiled libiconv...
 > 
 > 
 > Any help would really be appreciated...
 
gcj on trunk has changed so that Class.forName() no longer uses the
stack unwinder, at least for compiled code.  However, thye unwinder is
still used in many other places.

Andrew.