The only rational solution to this problem is to completely forego the
JDK's capabilities and generate the file exclusively from the build
tooling. I expect that at some point we'll end up with a series of
tools which construct the exports list from annotated package-infos, the
requires list from a mapping or static list in the build, and a bunch of
build- and application-system specific miscellany besides. I don't
believe that any nontrivial program is likely to bundle a
module-info.java source file all, which makes me wonder if there's
actually a point to having support for it at all. Why write it when you
can generate it, and at the same time, keep all your build-related
information in one spot?
On 03/08/2016 02:06 PM, Paul Benedict wrote:
Robert, it's sounds like a chicken-and-egg problem. You need the module
name to compile but don't know it until you have compiled.
Too bad this file isn't XML so that any tool could read the module
information outside of compiling. That's what I advocated for a long time
but that battle has been lost.
Cheers,
Paul
On Tue, Mar 8, 2016 at 1:36 PM, Robert Scholte <rfscho...@apache.org> wrote:
On Mon, 07 Mar 2016 14:53:28 +0100, Sander Mak <sander....@luminis.eu>
wrote:
I don't think I understand the issue here. Using -Xpatch doesn't change
the module declaration or export. It can be used to override or augment the
module content, it just can't override the module declaration. It can be
used in conjunction with -XaddReads and -XaddExports to read additional
modules or export additional packages. For example, if a patch adds types
to a new package then you could export that package with -XaddExports. If
the patch injects tests into an existing package then those tests might
have new dependences and requires compiling or running with
-XaddReads:$MODULE=junit for example.
I was playing around with exactly this yesterday, and this is what I
ended up with:
javac -Xmodule:javamodularity.easytext.algorithm.naivesyllablecounter \
-XaddReads:javamodularity.easytext.algorithm.naivesyllablecounter=org.junit
\
-mp mods:lib-test \
-d mods-test/javamodularity.easytext.algorithm.naivesyllablecounter
$(find src-test -name '*.java')
java -Xpatch:mods-test \
-XaddReads:javamodularity.easytext.algorithm.naivesyllablecounter=org.junit
\
-XaddExports:javamodularity.easytext.algorithm.naivesyllablecounter/javamodularity.easytext.algorithm.naivesyllablecounter=org.junit
\
-mp mods:lib-test \
-addmods
javamodularity.easytext.algorithm.naivesyllablecounter,hamcrestcore \
-m org.junit/org.junit.runner.JUnitCore
javamodularity.easytext.algorithm.naivesyllablecounter.NaiveSyllableCounterTest
Which patches my application module to contain a unit test, and then
exposes my application module to junit at runtime (which is used as
automatic module here). This works as expected.
-- Sander
When translating this to Maven it assumes that Maven is aware of the
module name of the project is it building.
Up until now that's not true. Developers specify the moduleName in the
module-info.java and it doesn't make sense to ask them to add the same
modulename to the pom (it that was possible) or the maven-compiler-plugin
configuration. Instead Maven could use some new java9 APIs to discover the
moduleName, but that would imply that from now on maven-compiler-plugin
requires Java9 runtime. I don't think that's the way we want to go right
now. Several Maven plugins have their own kind of multi-release pattern
where some codeblocks depend on a specific Maven version, but we really
want to avoid this.
I hope we can find a way where Maven can simply refer to the
classes-directory or the jar for some java/javac arguments where one would
now need to be aware of its module name.
From Mavens point of view the output directories are facts, dependencies
from the pom.xml too, as is the packaged artifact name & location, the
content of java files are a mystery and not of any interest (at least in a
classpath world ;) ).
thanks,
Robert
--
- DML
