the troubles with Java on old Win CE device.

[Michael Borgwardt]

I have an old Windows CE 2.1 device with MIPS CPU.
The only one VM I have found for this device is pocket-Java 1.0 (Sun). There
was probably some VM by Micorsoft, but I cannot find it (MS annihilated
every mention about it on the site).
I found that classes created by default Java compiler (from JDKs) don't
work: the message "class XXX is not found" appeared. But classes created by
Jikes compiler works fine.
I have no idea why does it happend. Are several specifications of
class-files existed?
Yes.

Classes that was created by Jikes are larger in size...
Perhabs I should turn some option in compiler?

Yes, specifically the -target 1.1 option
Not sure if that will run if the JVM really only supports Java 1.0

The second problem is that there is no Swing library included into that VM.
I hope it is nevertheless possible to use the Swing there if I recompile it
all using Jikes.

No, that won't work. But including the old Swing JARs, from the time when it was
distributed separately might. You can find that old release here:
http://java.sun.com/products/archive/jfc/1.1.1/index.html
Or maybe this older version fits your JVM better:
http://java.sun.com/products/archive/jfc/1.0.3/index.html

 

[Michael Shestero]

I have an old Windows CE 2.1 device with MIPS CPU.
The only one VM I have found for this device is pocket-Java 1.0 (Sun). There
was probably some VM by Micorsoft, but I cannot find it (MS annihilated
every mention about it on the site).
I found that classes created by default Java compiler (from JDKs) don't
work: the message "class XXX is not found" appeared. But classes created by
Jikes compiler works fine.
I have no idea why does it happend. Are several specifications of
class-files existed? Classes that was created by Jikes are larger in size...
Perhabs I should turn some option in compiler?

The second problem is that there is no Swing library included into that VM.
I hope it is nevertheless possible to use the Swing there if I recompile it
all using Jikes. But I cannot find the good sources of Swing in the Net. I
would be glad to have several ones. Now I have only one, and it doesn't want
to compile even with standart compiler. I have got also SwingGW sources, but
I see they depended on several libraries that is given without sources and
used the platform-depended binaries, so it will scarcely work under Win CE.

Michael

 

[Michael Shestero]

I have an old Windows CE 2.1 device with MIPS CPU. The only one VM I
have found for this device is pocket-Java 1.0 (Sun). There was probably some
VM by Micorsoft, but I cannot find it (MS annihilated every mention about it
on the site).work: the message "class XXX is not found" appeared. But classes created by
Jikes compiler works fine.
[...]

No, that won't work.

Why it doesn't work? I thought the Swing is just a library of classes
written in pure Java, so having the source I can rebuild it.(?)
I would like to know more about "different versions of specifications of
class-files". They are in strict accordance with the version of Java
language (version of JDK), aren't they? Can I compile/run the source written
on Java version X into binary bite-code version Y? (of couse I would like to
have X>Y).

But including the old Swing JARs, from the time when it was
distributed separately might. You can find that old release here:
http://java.sun.com/products/archive/jfc/1.1.1/index.html
Or maybe this older version fits your JVM better:
http://java.sun.com/products/archive/jfc/1.0.3/index.html

I tried the fitst one, and it seems to begin work.
But my application couldn't start because it call new methods and classes
which are absentv in this version of Swing.

Michael

 

[Michael Borgwardt]

Why it doesn't work? I thought the Swing is just a library of classes
written in pure Java, so having the source I can rebuild it.(?)

Yes, but only if you have all the classes it depends on, and I think the
Swing libraries included in the SDK make use of some APIs not present
in older Java versions.

But if you want to try, the source code of all the API classes (including
Swing) comes with the SDK, in a file "src.zip" in the base directory of
the SDK installation - though you have the option not to install it
during the SDK installation.

I would like to know more about "different versions of specifications of
class-files". They are in strict accordance with the version of Java
language (version of JDK), aren't they?

Not sure what you mean with this. The spec versions are defined by Sun and
each version of the JDK understands at least the version it produces and
lower ones. But the version numbers are completely different from the
JDK version numbers.

Can I compile/run the source written
on Java version X into binary bite-code version Y? (of couse I would like to
have X>Y).

That's what the -target option of javac does, though it uses the JDK version
numbers.