[patch] Support New NIO in IcedTea

[Andrew John Hughes]

On 01/09/2008, C. K. Jester-Young <cky944 at gmail.com> wrote:
> Hi Mark,
>
>
>  On Sun, Aug 31, 2008 at 04:41:33PM +0200, Mark Wielaard wrote:
>  > Nice idea. I wasn't aware that NIO2 was progressing already. I now see
>  > that my ignorance was partly because it seems this work is done in the
>  > nio/nio forest instead of in the jdk7/nio2 forest. Do you know how they
>  > relate?
>
>
> Looking at the jdk7/nio2, the last push was in February. The current
>  nio2 stuff seemed to have been established in April (see, e.g., [1]),
>  by different parties. But I'm not involved in NIO2 currently, let alone
>  back then, so I can't really say anything.
>
>  [1] http://mail.openjdk.java.net/pipermail/nio-dev/2008-April/000001.html
>
>
>  > Also, how do you keep track of which commits are really nio2 related and
>  > which ones are the commits that just sync with the master jdk7 repo? It
>  > would be nice to have an easy way to see just those changes/commits made
>  > for the new nio support.
>
>
> Yes, I'm much wondering about the same question myself. One of my
>  aspirations is to have an IcedTea build that incorporates multiple
>  projects simultaneously (NIO2, MLVM/Da Vinci Machine, and BGGA Closures
>  are three of the ones I have an interest in), and being able to work
>  with _just_ the diffs would be nice.
>
>  On that note, the MLVM project works as a set of patches against the
>  mainline jdk7 code (although I have had some success applying it
>  against the NIO2 code too). It uses the Mercurial mq extension for
>  doing all the patching, and patches can be marked as being for specific
>  releases of jdk7, for example.
>
>
>  > Do you need any special tag to get that tag? While building with your
>  > patch applied and doing just:
>  > autoreconf --force --install \
>  >   && ./configure --enable-hg --with-project=nio2 \
>  >   && make
>
>
> The tip revision is, at the time of writing, at -b94. I successfully
>  built with the supplied patches on Ubuntu 8.04, on amd64. Just to test
>  portability, I'm now building within a 32-bit chroot, just to see if
>  it works correctly there too.
>
>  (This process is a notorious PITA; I've had to write a fakeuname.so
>  to ``convince'' the build tools that I'm building on a 32-bit machine,
>  because some of the scripts don't respect the --build option that I
>  sent to configure.)
>
>  Here are the configure arguments I used:
>
>  ./configure --with-openjdk --with-openjdk-home=/usr/lib/jvm/java-6-openjdk \
>
> --enable-hg --with-project=nio2
>
>
> In other words, I'm building with OpenJDK 6 as supplied with Ubuntu.
>  (With the icedtea-implicit-enable-hg.diff I recently sent, that makes
>  the --enable-hg option redundant. My patch is, by the way, designed to
>  be applied to IcedTea revision 1158.)
>
>  I noticed from your build output that you're also using 1.6 javac for
>  bootstrapping; is that a Sun build, or from IcedTea? Should it make
>  a difference?
>

It's not javac, it's ecj.

>
>  > I got:
>  >         /home/mark/src/icedtea/bootstrap/jdk1.6.0/bin/javac  -g \
>  >           -d lib/hotspot-tools \
>  >           -source 1.5 \
>  >           -sourcepath \
>  >             'hotspot-tools:openjdk/jdk/src/share/classes:openjdk/jdk/src/solaris/classes:openjdk/langtools/src/share/classes:openjdk/jaxp/src/share/classes:openjdk/corba/src/share/classes:openjdk/jaxws/src/share/classes:/home/mark/src/icedtea/generated:/home/mark/src/icedtea/rt' \
>  >           -bootclasspath '' @hotspot-tools-source-files.txt ; \
>  >       fi
>  > incorrect classpath: hotspot-tools/com/sun/codemodel/internal/ClassType.java
>
>
> This is very odd. The first line in hotspot-tools-source-files.txt is
>  indeed hotspot-tools/com/sun/codemodel/internal/ClassType.java, which
>  means that whatever make system you have is not passing the '' argument
>  before it. Either that, or the javac you have is disregarding it.
>

Could be the opening " after bootclasspath without a closing one.

>
>  > 1. ERROR in /home/mark/src/icedtea/openjdk/jdk/src/share/classes/java/nio/channels/spi/AbstractInterruptibleChannel.java (at line 144)
>  >       public void disableInterruptor(AbstractInterruptibleChannel ch) {
>  >                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>  > The method disableInterruptor(AbstractInterruptibleChannel) of type new JavaNioChannelsSpiAccess(){} must override a superclass method
>
>
> This is to do with your javac too. Some compilers support the @Override
>  annonation being applied to interface methods, it seems, whereas other
>  ones don't. I haven't quite figured out which ones do/don't allow it.
>

Only very recent versions of ecj do, not those shipped with distros at present.

>  I remember seeing some IcedTea patches whose sole purpose is to remove
>  @Override annotations that would choke some compilers. However, since I
>  don't have such a compiler, working out which @Override annotation to
>  remove would be difficult task, since I presume the best way to find
>  them is by trial and error. :-)
>

Yes, patches/icedtea-override.patch.  Which compiler are you using with IcedTea?
The default build should use ecj unless you are building with an
existing IcedTea tree
(--with-icedtea).

>
>  > Did I get the wrong nio tree, or did I apply the patch wrongly?
>
>
> No, and no, it seems. :-)
>
>
>  > There are no real legal requirements except for making sure every
>  > contribution is free software. But it is encouraged to push anything
>  > upstream into openjdk of course to keep divergence as low as possible.
>
>
> Cool, thanks for the clarification!
>
>
>  > Thanks for working on this, nio2 is very exciting.
>
>
> No worries, and yes, I'm totally keen to get this working on IcedTea!
>
>  Many thanks,
>         ---Chris K.
>

Thanks,
-- 
Andrew :-)

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