GCJ Swing/AWT working on OS X -- article

[John Gabriele]

On Jul 21, 2004, at 9:01 PM, Bryce McKinlay wrote:

> John Gabriele wrote:
>
>> Thanks Bryce.
>>
>> Should I be adding a '-l' arg to my build command line?
>> (note, my gnome-related libs are in ~/src/gnome/objdir/lib)
>> Hmm... here's what that gets me:
>>
>> ~/temp/gcj_stuff $ gcj -o baz --main=TestAWT -l  
>> ~/src/gnome/objdir/lib TestAWT.java
>> /usr/bin/ld: can't locate file for: -l/Users/john/src/gnome/objdir/lib
>> collect2: ld returned 1 exit status
>
>
> Normally, libgcj will look for the toolkit classes in a file called  
> lib-gnu-java-awt-peer-gtk.so (.dylib on OS X) in your LD_LIBRARY_PATH  
> (DYLD_LIBRARY_PATH on OS X).
>
> So, try setting DYLD_LIBRARY_PATH to point to the directory containing  
> lib-gnu-java-awt-peer-gtk.dylib. If that doesn't work, it is possible  
> that the library loading mechanism that libgcj uses is not working  
> correctly on OS X.
>
> Regards
>
> Bryce
>

Thanks for the reply Bryce.

Well, I've got gcc installed in /usr/local/gcc_cvs, and I had set
DYLD_LIBRARY_PATH to /usr/local/gcc_cvs/lib and had *not* set CLASSPATH,
so I think I was already doing what you suggest:


~/temp/gcj_stuff $ ls /usr/local/gcc_cvs/lib/lib*awt*
/usr/local/gcc_cvs/lib/lib-gnu-java-awt-peer-gtk.6.0.0.dylib*    
/usr/local/gcc_cvs/lib/lib-gnu-java-awt-peer-gtk.dylib@
/usr/local/gcc_cvs/lib/lib-gnu-java-awt-peer-gtk.6.dylib@        
/usr/local/gcc_cvs/lib/lib-gnu-java-awt-peer-gtk.la*


~/temp/gcj_stuff $ echo $CLASSPATH



~/temp/gcj_stuff $ echo $DYLD_LIBRARY_PATH
/usr/local/gcc_cvs/lib


~/temp/gcj_stuff $ ls
TestAWT.java


~/temp/gcj_stuff $ gcj -o baz --main=TestAWT TestAWT.java
/usr/bin/ld: warning multiple definitions of symbol _sqrt
/usr/local/gcc_cvs/lib/gcc/powerpc-apple-darwin7.4.0/3.5.0/../../../ 
libgcj.dylib(libgcj.6.0.0.dylib-master.o) definition of _sqrt
/usr/lib/libm.dylib(sqrt970.o) definition of _sqrt


~/temp/gcj_stuff $ ls -l
total 344
-rw-r--r--  1 john  john   14126 21 Jul 18:47 TestAWT.java
-rwxr-xr-x  1 john  john  156620 21 Jul 21:17 baz*


~/temp/gcj_stuff $ ./baz
Exception in thread "main" java.awt.AWTError: Cannot load AWT toolkit:  
gnu.java.awt.peer.gtk.GtkToolkit
    <<No stacktrace available>>
Caused by: java.lang.ClassNotFoundException:  
gnu.java.awt.peer.gtk.GtkToolkit not found in [file:./, core:/]
    <<No stacktrace available>>


Does /usr/local/gcc_cvs/share/java/libgcj-3.5.0.jar internally make use
   of /usr/local/gcc_cvs/lib/lib-gnu-java-awt-peer-gtk.6.0.0.dylib ?
Note: OS X comes with otool (rather than ldd), but unfortunately I
can't do this:

~/temp/gcj_stuff $ otool -L  
/usr/local/gcc_cvs/share/java/libgcj-3.5.0.jar
/usr/local/gcc_cvs/share/java/libgcj-3.5.0.jar: is not an object file


You mentioned:
> Odd. For some reason the compiled versions of the Gtk AWT peer classes  
> couldn't be found. By putting them on the classpath, you'll be running  
> interpreted bytecode, not natively compiled code. This will reduce  
> performance.

How can I tell when I'm running natively compiled code vs. when I'm
running interpreted bytecode?


~/temp/gcj_stuff $ export  
CLASSPATH=/usr/local/gcc_cvs/share/java/libgcj-3.5.0.jar


~/temp/gcj_stuff $ gcj -o baz2 --main=TestAWT TestAWT.java
/usr/bin/ld: warning multiple definitions of symbol _sqrt
/usr/local/gcc_cvs/lib/gcc/powerpc-apple-darwin7.4.0/3.5.0/../../../ 
libgcj.dylib(libgcj.6.0.0.dylib-master.o) definition of _sqrt
/usr/lib/libm.dylib(sqrt970.o) definition of _sqrt


~/temp/gcj_stuff $ ls -l
total 344
-rw-r--r--  1 john  john   14126 21 Jul 18:47 TestAWT.java
-rwxr-xr-x  1 john  john  156620 21 Jul 21:40 baz2*


~/temp/gcj_stuff $ otool -L baz2
baz2:
         /usr/local/gcc_cvs/lib/libgcc_s.1.0.dylib (compatibility  
version 1.0.0, current version 1.0.0)
         /usr/local/gcc_cvs/lib/libgcj.6.dylib (compatibility version  
7.0.0, current version 7.0.0)
         /usr/lib/libSystem.B.dylib (compatibility version 1.0.0,  
current version 71.1.1)
         /usr/lib/libiconv.2.dylib (compatibility version 5.0.0, current  
version 5.0.0)
         /usr/lib/libmx.A.dylib (compatibility version 1.0.0, current  
version 47.0.0)


~/temp/gcj_stuff $ ./baz2
false
true
-- listing properties --
path.separator=:
java.vm.name=GNU libgcj
awt.toolkit=gnu.java.awt.peer.gtk.GtkToolkit
java.vm.specification.name=Java(tm) Virtual Machine Specification
java.home=/usr/local/gcc_cvs
java.vm.specification.version=1.0
line.separator=

java.vm.specification.vendor=Sun Microsystems Inc.
gnu.classpath.home.url=file:///usr/local/gcc_cvs/lib
gnu.gcj.progname=./baz2
java.specification.version=1.3
java.library.path=
gnu.classpath.vm.shortname=libgcj
java.class.version=46.0
java.specification.name=Java(tm) Platform API Specification
os.version=7.4.0
gnu.classpath.home=/usr/local/gcc_cvs
user.home=/Users/john
file.encoding=US-ASCII
os.name=Darwin
user.name=john
java.class.path=/usr/local/gcc_cvs/share/java/libgcj-...
java.io.tmpdir=/tmp
os.arch=Power Macintosh
java.fullversion=GNU libgcj 3.5.0 20040718 (experimental)
user.language=en
java.specification.vendor=Sun Microsystems Inc.
user.dir=/Users/john/temp/gcj_stuff
java.vm.info=GNU libgcj 3.5.0 20040718 (experimental)
java.version=3.5.0
java.ext.dirs=/usr/local/gcc_cvs/share/java/ext
sun.boot.class.path=/usr/local/gcc_cvs/share/java/libgcj-...
java.vm.vendor=Free Software Foundation, Inc.
java.vendor.url=http://gcc.gnu.org/java/
java.vendor=Free Software Foundation, Inc.
file.separator=/
java.vm.version=3.5.0 20040718 (experimental)
gnu.cpu.endian=big
user.region=US


Thanks for any insights,
---J