[news.eclipse.platform.swt] Re: What is in swt-pi.jar

["Veronika Irvine" <veronika_irvine@xxxxxxx>]

The swt.jar contains platform specific Java code.  In the case of GTK, the
platform specific code in swt.jar calls the GTK JNI binding in swt-pi.jar.
On all other platforms so far, there is no need to separate out the JNI
layer.  Note, the JNI layer in SWT is a one to one mapping with the OS
calls.  It does not try to implement a "peer-layer" in C that is common
across all platforms.  That is why both the swt.jar and swt-pi.jar must be
the ones for the GTK port.

> So what will happen if I specify swt.jar from motif and swt-pi.jar
> from gtk in my classpath and then start a swt App?
The swt.jar for motif does not call any GTK JNI stuff so you will get the
motif implementation of SWT (the motif JNI layer is included in the motif
swt.jar).  The swt-pi.jar will be ignored.   You will need to have the motif
libraries in the library path.

> BTW. What is the policy for breaking API changes in SWT?
If the package has "internal" in the name it may change at any time.
Otherwise, we try very hard not to change any API.


"Jan Schulz" <muelleimer@xxxxxxxxxxxxxxxxx> wrote in message
news:slrnbh5jsm.nja.muelleimer@xxxxxxxxxxxxxxxxxxxx
> Hallo!
>
> * Veronika Irvine <veronika_irvine@xxxxxxx> wrote:
> > You need both jar files when running SWT applications.
> > The swt-pi.jar contains a JNI binding for GTK OS level calls.
> > The reason for the two jars on GTK is for compatability with the LGPL
> > license of the GTK OS layer.  If you look at the about.html file in
> > org.eclipse.swt.gtk you will see a description of this.
>
> Thanks for pointing that out. I didn't realize that swt.gtk is partly
> under LGPL...
>
> So what will happen if I specify swt.jar from motif and swt-pi.jar
> from gtk in my classpath and then start a swt App?
>
> Will every 'license-problem' part of swt be released with the name
> 'swt-pi.jar' (FOX toolkit?)?
>
> I'm not really firm in that sections. I want to enable gtk and motif
> bindings under debian (with SWT Apps, eclipse is running with the
> right -ws value). For that I want to put swt.jar (under the name
> swt2.1.jar, to be in line with debians library naming) under
> 'update-alternative', which generates symlinks to the chosen
> implementation (swt2.1-motif.jar or swt2.1-gtk.jar up to now).
>
> So I'm now facing the problem what to do with swt-pi.jar...
>
> BTW. What is the policy for breaking API changes in SWT?
>
> Jan