Agree with David on that.

Regards
JB

On Wed, Dec 13, 2023 at 8:17 PM David Li <lidav...@apache.org> wrote:
>
> I think we will just have to live with requiring different flags for 
> different modules. If we can detect the lack of the flag at runtime somehow 
> and present an appropriate error message (the way we do for the memory 
> module) that would be best.
>
> On Wed, Dec 13, 2023, at 12:33, James Duong wrote:
> > For the work on modularization, I’ve merged the flight-grpc and
> > flight-core modules. I haven’t moved any other packages.
> >
> > I also encountered this problem with flight-core. Flight-core derives
> > from io.netty.buffer (specifically CompositeByteBuf), but we cannot use
> > Netty buffer with JPMS without requiring users to monkey-patch it with
> > patch-module. I have flight-core using Netty buffer on the classpath,
> > but deriving from CompositeByteBuf requires adding
> > --add-reads=org.apache.arrow.flight.core=ALL-UNNAMED to the command
> > line since Netty’s being treated as part of the unnamed module in this
> > context.
> >
> > This isn’t terribly onerous from the user’s perspective (especially
> > compared to monkey-patching), but we start getting into the business of
> > having different command-line arguments for different modules the user
> > might be using.
> >
> > We could tell users to always add
> > –add-reads=org.apache.arrow.flight.core=ALL-UNNAMED, but if they aren’t
> > using Flight, they’ll get a warning about an unrecognized module. Any
> > thoughts about the best way to present these command-line changes?
> >
> >
> > From: Jean-Baptiste Onofré <j...@nanthrax.net>
> > Date: Wednesday, December 13, 2023 at 6:58 AM
> > To: dev@arrow.apache.org <dev@arrow.apache.org>
> > Subject: Re: [DISC][Java]: Migrate Arrow Java to JPMS Java Platform
> > Module System
> > Hi,
> >
> > We have a "split packages" between flight-core and flight-grpc. I
> > don't think anyone is using only flight-core to create a new
> > "transport".
> > I think it's acceptable to combine flight-core and flight-grpc, and
> > maybe reshape a bit (imho some classes from flight-grpc should be
> > actually in flight-core).
> > Users can always reshade (even if it's painful).
> >
> > Regards
> > JB
> >
> > On Tue, Dec 12, 2023 at 8:52 PM David Li <lidav...@apache.org> wrote:
> >>
> >> I would be OK with combining flight-core and flight-grpc. It's not clear 
> >> to me anyways that the current split would actually be helpful if we do 
> >> ever want to support Flight without gRPC.
> >>
> >> On Tue, Dec 12, 2023, at 14:21, James Duong wrote:
> >> > An update on this work.
> >> >
> >> > I’ve been able to update the following to JPMS modules now:
> >> >
> >> >   *   arrow-memory-core
> >> >   *   arrow-memory-unsafe
> >> >   *   arrow-format
> >> >   *   arrow-vector
> >> >   *   arrow-compression
> >> >   *   arrow-tools
> >> >   *   arrow-avro
> >> >   *   arrow-jdbc
> >> >   *   arrow-algorithm
> >> >
> >> > I don’t think the following should be modularized (but would appreciate
> >> > feedback as well):
> >> >
> >> >   *   arrow-performance (test-only module)
> >> >   *   flight-integration-tests (test-only module)
> >> >   *   flight-jdbc-core
> >> >   *   flight-jdbc-driver (Need to think about this. MySQL suggests they
> >> > want to modularize their JDBC driver:
> >> > https://bugs.mysql.com/bug.php?id=97683 . How does this interact with
> >> > the ServiceLoader changes in JPMS as well).
> >> >
> >> > I’m starting the flight-related modules now. The first issue I’ve
> >> > noticed is that flight-core and flight-grpc reuse packages. I’d like to
> >> > combine flight-core and flight-grpc because of this (currently we only
> >> > have Flight using grpc in Java).
> >> >
> >> > After Flight I’d take a look at the modules that have native code:
> >> >
> >> >   *   arrow-c-data
> >> >   *   arrow-orc
> >> >   *   arrow-dataset
> >> >   *   arrow-gandiva
> >> >
> >> >
> >> > From: James Duong <james.du...@improving.com.INVALID>
> >> > Date: Tuesday, December 5, 2023 at 1:39 PM
> >> > To: dev@arrow.apache.org <dev@arrow.apache.org>
> >> > Subject: Re: [DISC][Java]: Migrate Arrow Java to JPMS Java Platform
> >> > Module System
> >> > I expect that we’d still have to change CLI arguments in JDK17.
> >> >
> >> > The need for changing the CLI arguments is due to memory-core now being
> >> > a named module while requiring access to Unsafe and using reflection
> >> > for accessing internals of java.nio.Buffer.
> >> >
> >> > We’re using JDK8 code for doing both currently. It might be worth
> >> > looking into if there’s a JDK9+ way of doing this without needing
> >> > reflection and compiling memory-core as a multi-release JAR.
> >> >
> >> > I don’t expect more CLI argument changes unless we use reflection on
> >> > NIO classes in other modules.
> >> >
> >> >
> >> > From: Adam Lippai <a...@rigo.sk>
> >> > Date: Tuesday, December 5, 2023 at 9:28 AM
> >> > To: dev@arrow.apache.org <dev@arrow.apache.org>
> >> > Subject: Re: [DISC][Java]: Migrate Arrow Java to JPMS Java Platform
> >> > Module System
> >> > I believe Spark 4.0 was mentioned before. It’ll require Java 17 and
> >> > will be
> >> > released in a few months (June?).
> >> >
> >> > Best regards,
> >> > Adam Lippai
> >> >
> >> > On Tue, Dec 5, 2023 at 12:05 David Li <lidav...@apache.org> wrote:
> >> >
> >> >> Thanks James for delving into this mess.
> >> >>
> >> >> It looks like this change is unavoidable if we want to modularize? I 
> >> >> think
> >> >> this is OK. Will the CLI argument change as we continue modularizing, 
> >> >> or is
> >> >> this the only change that will be needed?
> >> >>
> >> >> On Mon, Dec 4, 2023, at 20:07, James Duong wrote:
> >> >> > Hello,
> >> >> >
> >> >> > I did some work to separate the below PR into smaller PRs.
> >> >> >
> >> >> >
> >> >> >   *   Updating the versions of dependencies and maven plugins is done
> >> >> > and merged into master.
> >> >> >   *   I separated out the work modularizing arrow-vector,
> >> >> > arrow-memory-core/unsafe, and arrow-memory-netty.
> >> >> >
> >> >> > Modularizing arrow-memory-core requires a smaller change to user
> >> >> > command-line arguments. Instead of:
> >> >> > --add-opens=java.base/java.nio=ALL-UNNAMED
> >> >> >
> >> >> > The user needs to add:
> >> >> > --add-opens=java.base/java.nio=org.apache.arrow.memory.core,ALL-UNNAMED
> >> >> >
> >> >> > I initially tried to modularize arrow-vector separately from
> >> >> > arrow-memory-core but found that any meaningful operation in
> >> >> > arrow-vector would trigger an illegal access in memory-core if it
> >> >> > wasn’t modularized.
> >> >> >
> >> >> > I was able to run the tests for arrow-compression and arrow-tools
> >> >> > successfully after modularizing memory-core, memory-unsafe-, and
> >> >> > arrow-vector. Note that I had more success by making memory-core and
> >> >> > memory-unsafe automatic modules.
> >> >> >
> >> >> > I think we should make a decision here on if we want to bite the 
> >> >> > bullet
> >> >> > and introduce a breaking user-facing change around command-line
> >> >> > options. The other option is to wait for JDK 21 to modularize. That’s
> >> >> > farther down the line and requires refactoring much of the memory
> >> >> > module code and implementing a module using the foreign memory
> >> >> > interface.
> >> >> >
> >> >> > From: James Duong <james.du...@improving.com.INVALID>
> >> >> > Date: Tuesday, November 28, 2023 at 6:48 PM
> >> >> > To: dev@arrow.apache.org <dev@arrow.apache.org>
> >> >> > Subject: Re: [DISC][Java]: Migrate Arrow Java to JPMS Java Platform
> >> >> > Module System
> >> >> > Hi,
> >> >> >
> >> >> > I’ve made some major progress on this work in this PR:
> >> >> > https://github.com/apache/arrow/pull/38876
> >> >> >
> >> >> >
> >> >> >   *   The maven plugin for compiling module-info.java files using JDK 
> >> >> > 8
> >> >> > is working correctly.
> >> >> >   *   arrow-format, arrow-memory-core, arrow-memory-netty,
> >> >> > arrow-memory-unsafe, and arrow-vector have been modularized
> >> >> > successfully.
> >> >> >      *   Tests pass locally for all of these modules.
> >> >> >      *   They fail in CI. This is likely from me not updating a 
> >> >> > profile
> >> >> > somewhere.
> >> >> >
> >> >> > Similar to David’s PR from below, arrow-memory and modules needed to 
> >> >> > be
> >> >> > refactored fairly significantly and split into two modules: a
> >> >> > public-facing JPMS module and a separate module which adds to Netty’s
> >> >> > packages (memory-netty-buffer-patch). What’s more problematic is that
> >> >> > because we are using named modules now, users need to add more
> >> >> > arguments to their Java command line to use arrow. If one were to use
> >> >> > arrow-memory-netty they would need to add the following:
> >> >> >
> >> >> > --add-opens java.base/jdk.internal.misc=io.netty.common
> >> >> >
> >> >> --patch-module=io.netty.buffer=${project.basedir}/../memory-netty-buffer-patch/target/arrow-memory-netty-buffer-patch-${project.version}.jar
> >> >>
> >> >> >
> >> >> --add-opens=java.base/java.nio=org.apache.arrow.memory.core,io.netty.common,ALL-UNNAMED
> >> >> >
> >> >> > Depending on where the memory-netty-buffer-patch JAR is located, and
> >> >> > what version, the command the user needs to supply changes, so this
> >> >> > seems like it’d be really inconvenient.
> >> >> >
> >> >> > Do we want to proceed with modularizing existing memory modules? Both
> >> >> > netty and unsafe? Or wait until the new memory module from Java 21 is
> >> >> > available?
> >> >> >
> >> >> > The module-info.java files are written fairly naively. I haven’t
> >> >> > inspected thoroughly to determine what packages users will need.
> >> >> >
> >> >> > We can continue modularizing more components in a separate PR. Ideally
> >> >> > all the user breakage (class movement, new command-line argument
> >> >> > requirements) happens within one major Arrow version.
> >> >> >
> >> >> > From: James Duong <james.du...@improving.com.INVALID>
> >> >> > Date: Tuesday, November 21, 2023 at 1:16 PM
> >> >> > To: dev@arrow.apache.org <dev@arrow.apache.org>
> >> >> > Subject: Re: [DISC][Java]: Migrate Arrow Java to JPMS Java Platform
> >> >> > Module System
> >> >> > I’m following up on this topic.
> >> >> >
> >> >> > David has a PR from last year that’s done much of the heavy lifting 
> >> >> > for
> >> >> > refactoring the codebase to be package-friendly.
> >> >> > https://github.com/apache/arrow/pull/13072
> >> >> >
> >> >> > What’s changed since and what’s left:
> >> >> >
> >> >> >   *   New components have been added (Flight SQL for example) that 
> >> >> > will
> >> >> > need to be updated for modules.
> >> >> >   *   There wasn’t a clear solution on how to do this without breaking
> >> >> > JDK 8 support. Compiling module-info.java files require using JDK9, 
> >> >> > but
> >> >> > using JDK9 breaks using JDK8 methods of accessing sun.misc.Unsafe.
> >> >> >      *   There is a Gradle plugin that can compile module-info.java
> >> >> > files purely syntactically that we can adapt to maven. It has
> >> >> > limitations (the one I see is that it can’t iterate through
> >> >> > classloaders to handle annotations), but using this might be a good
> >> >> > stopgap until we JDK 8 support is deprecated.
> >> >> >   *   Some plugins need to be updated:
> >> >> >      *   maven-dependency-plugin 3.0.1 can’t parse module-info.class
> >> >> > files.
> >> >> >      *   checkstyle 3.1.0 can’t parse module-info.java files. Our
> >> >> > existing checkstyle rules file can’t be loaded with newer versions. We
> >> >> > can exclude module-info.java for now and have a separate Issue for
> >> >> > updating checkstyle itself and the rules file.
> >> >> >   *   grpc-java could not be modularized when the PR above was 
> >> >> > written.
> >> >> >      *   Grpc 1.57 now can be modularized
> >> >> > (grpc/grpc-java#3522<https://github.com/grpc/grpc-java/issues/3522>)
> >> >> >
> >> >> > From: David Dali Susanibar Arce <davi.sar...@gmail.com>
> >> >> > Date: Wednesday, May 25, 2022 at 5:02 AM
> >> >> > To: dev@arrow.apache.org <dev@arrow.apache.org>
> >> >> > Subject: [DISC][Java]: Migrate Arrow Java to JPMS Java Platform Module
> >> >> System
> >> >> > Hi All,
> >> >> >
> >> >> > This email's purpose is a request for comments to migrate Arrow Java 
> >> >> > to
> >> >> JPMS
> >> >> > Java Platform Module System <
> >> >> https://openjdk.java.net/projects/jigsaw/spec/><https://openjdk.java.net/projects/jigsaw/spec/%3e><https://openjdk.java.net/projects/jigsaw/spec/%3e%3chttps:/openjdk.java.net/projects/jigsaw/spec/%3e%3e><https://openjdk.java.net/projects/jigsaw/spec/%3e%3chttps:/openjdk.java.net/projects/jigsaw/spec/%3e%3e%3chttps:/openjdk.java.net/projects/jigsaw/spec/%3e%3chttps:/openjdk.java.net/projects/jigsaw/spec/%3e%3e%3e>
> >> >> > JSE 9+ (1).
> >> >> >
> >> >> > Current status:
> >> >> >
> >> >> > - Arrow Java use JSE1.8 specification
> >> >> >
> >> >> > - Arrow Java works with JSE1.8/9/11/17
> >> >> >
> >> >> > - This is possible because Java offers “legacy mode”
> >> >> >
> >> >> > Proposal:
> >> >> >
> >> >> > Migrate to JPMS Java Platform Module System. This Draft PR
> >> >> > <https://github.com/apache/arrow/pull/13072>(2<
> >> >> https://github.com/apache/arrow/pull/13072%3e(2<<https://github.com/apache/arrow/pull/13072%3e(2%3c><https://github.com/apache/arrow/pull/13072%3e(2%3c%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3c%3e><https://github.com/apache/arrow/pull/13072%3e(2%3c%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3c%3e%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3c%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3c%3e%3e>
> >> >> https://github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2
> >> >> <
> >> >> https://github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2>>>)<https://github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3e%3e%3e)><https://github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3e%3e%3e)%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3e%3e%3e)%3e><https://github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3e%3e%3e)%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3e%3e%3e)%3e%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3e%3e%3e)%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3chttps:/github.com/apache/arrow/pull/13072%3e(2%3e%3e%3e)%3e%3e>
> >> >>
> >> >> > contains an initial port of
> >> >> > the modules: Format / Memory Core / Memory Netty / Memory Unsafe /
> >> >> > Vector
> >> >> > for evaluation.
> >> >> >
> >> >> > Main Reason to migrate:
> >> >> >
> >> >> > - JPMS offer Strong encapsulation, Well-defined interfaces
> >> >> > <https://github.com/nipafx/demo-jigsaw-reflection>, Explicit
> >> >> dependencies.
> >> >> > <https://nipafx.dev/java-modules-reflection-vs-encapsulation/> (3)(4)
> >> >> >
> >> >> > - JPMS offer reliable configuration and security to hide platform
> >> >> internals.
> >> >> >
> >> >> > - JPMS offers a partial solution to solve problems about read (80%)
> >> >> /write
> >> >> > (20%) code.
> >> >> >
> >> >> > - JPMS offer optimization for readability about read/write ratio 
> >> >> > (90/10)
> >> >> > thru module-info.java.
> >> >> >
> >> >> > - Consistency logs, JPMS implement consistency logs to really use 
> >> >> > that to
> >> >> > solve the current problem.
> >> >> >
> >> >> > - Be able to customize JRE needed with only modules needed (not
> >> >> > java.desktop for example and others) thru JLink.
> >> >> >
> >> >> > - Modules have also been implemented by other languages such as
> >> >> Javascript
> >> >> > (ES2015), C++(C++20), Net (Nuget/NetCore)..
> >> >> >
> >> >> > - Consider taking a look at this discussion about pros/cons
> >> >> > <
> >> >> https://www.reddit.com/r/java/comments/okt3j3/do_you_use_jigsaw_modules_in_your_java_projects/
> >> >> >
> >> >> > (5).
> >> >> >
> >> >> > - Eventual migration to JPMS is a practical necessity as more projects
> >> >> > migrate.
> >> >> >
> >> >> > Effort:
> >> >> >
> >> >> > - First of all we need to decide to move from JSE1.8 to JSE9+ or be 
> >> >> > able
> >> >> to
> >> >> > offer support for both jar components JSE1.8 and JSE9+ included.
> >> >> >
> >> >> > - Go bottom up for JPMS.
> >> >> >
> >> >> > - Packages need to be unique (i.e. org.apache.arrow.memory /
> >> >> > io.netty.buffer). Review Draft PR with initial proposal.
> >> >> >
> >> >> > - Dependencies also need to be modularized. If some of our current
> >> >> > dependencies are not able to be used as a module this will be a 
> >> >> > blocker
> >> >> for
> >> >> > our modules (we could patch that but this is an extra effort).
> >> >> >
> >> >> > Killers:
> >> >> >
> >> >> > - FIXME! I need your support to identify killer reasons to be able to
> >> >> push
> >> >> > this implementation.
> >> >> >
> >> >> > Please let us know if Arrow Java to JPMS Java Platform Module System 
> >> >> > is
> >> >> > needed and should be implemented.
> >> >> >
> >> >> > Please use this file for any comments
> >> >> >
> >> >> https://docs.google.com/document/d/1qcJ8LPm33UICuGjRnsGBcm8dLI08MyiL8BO5JVzTutA/edit?usp=sharing
> >> >> >
> >> >> > Resources used:
> >> >> >
> >> >> > (1): https://openjdk.java.net/projects/jigsaw/spec/
> >> >> >
> >> >> > (2): https://github.com/apache/arrow/pull/13072
> >> >> >
> >> >> > (3): https://nipafx.dev/java-modules-reflection-vs-encapsulation/
> >> >> >
> >> >> > (4): https://github.com/nipafx/demo-jigsaw-reflection
> >> >> >
> >> >> > (5):
> >> >> >
> >> >> https://www.reddit.com/r/java/comments/okt3j3/do_you_use_jigsaw_modules_in_your_java_projects/
> >> >> >
> >> >> > Best regards,
> >> >> >
> >> >> > --
> >> >> > David
> >> >>

Reply via email to