Add Automatic Module Name

[eddumelendez]

Current version is using sun.misc.Unsafe. We should get remove this before to Use Automatic-Module-Name entry

jdeps --jdk-internals target/mybatis-3.4.6-SNAPSHOT.jar                                                                                                                   
mybatis-3.4.6-SNAPSHOT.jar -> jdk.unsupported
   org.apache.ibatis.javassist.util.proxy.DefineClassHelper -> sun.misc.Unsafe                                    JDK internal API (jdk.unsupported)

Warning: JDK internal APIs are unsupported and private to JDK implementation that are
subject to be removed or changed incompatibly and could break your application.
Please modify your code to eliminate dependence on any JDK internal APIs.
For the most recent update on JDK internal API replacements, please check:
https://wiki.openjdk.java.net/display/JDK8/Java+Dependency+Analysis+Tool

JDK Internal API                         Suggested Replacement
----------------                         ---------------------
sun.misc.Unsafe                          See http://openjdk.java.net/jeps/260

[kazuki43zoo]

The DefineClassHelper is Javassist's class. We need to wait releasing the next version of Javassist.

See https://github.com/jboss-javassist/javassist/blob/master/src/main/javassist/util/proxy/DefineClassHelper.java

[harawata]

Hi @eddumelendez @kazuki43zoo ,
Can we update Javassist to 3.23.1-GA and proceed with adding automatic module name?

[eddumelendez]

Hi @harawata I just updated the javassist version and there is no more warnings. Now, we can add manually the Automatic-Module-Name or we can add a maven phase in mybatis-parent for all mybatis projects.

WDYT?

[harawata]

Thank you for the update, @eddumelendez !

we can add a maven phase in mybatis-parent for all mybatis projects.

I like the idea.
Just to clarify, will there be any 'conflict' when we add module-info.java to some child projects in the future?

[hazendaz]

Hi, I haven't messed around with modules yet. What is the thinking on what would go in the parent and how does that impact the downstreams?

[harawata]

I guess no one is sure about it. :D
In that case, let's add Automatic-Module-Name locally for now.
It shouldn't be too hard to change it later.

By the way, what's the module name?
org.mybatis.core or just org.mybatis ?

[eddumelendez]

module name use to be the artifactId in this case just mybatis. For artifactIds with dash such as mybatis-spring would be mybatis.spring

[harawata]

@eddumelendez ,

Yeah, that's how module name is calculated from the JAR name implicitly.
When declaring Automatic-Module-Name explicitly, however, it should match the module name that will be declared in module-info.java and we should follow the 'reverse DNS' rule, I think.

I'm not sure why Spring chose the filename-based module name, but there must have been a good reason.

[kazuki43zoo]

I'm not sure why Spring chose the filename-based module name, but there must have been a good reason.

Attaches the issue link.

[kazuki43zoo]

I've investigated an "Automatic-Module-Name" on some libraries.

GroupId:ArtifactId	Automatic-Module-Name
com.zaxxer:HikariCP	com.zaxxer.hikari
org.junit.jupiter:junit-jupiter-engine	org.junit.jupiter.engine
com.fasterxml.jackson.core:jackson-databind	com.fasterxml.jackson.databind
org.mockito:mockito-core	org.mockito

[kazuki43zoo]

we should follow the 'reverse DNS' rule, I think.

👍 I think better that a module name start with org.mybatis.

e.g.)

mybatis -> org.mybatis or org.mybatis.core
mybatis-spring -> org.mybatis.spring
mybatis-cdi -> org.mybatis.cdi
mybatis-scala -> org.mybatis.scala
mybatis-redis -> org.mybatis.redis

WDYT?

[harawata]

Thanks @kazuki43zoo for the link.
I still couldn't really understand why they had to use the filename based naming, but it would be safe to say that Spring was a special case. :D

'core' seems unnecessary. So, +1 to 'org.mybatis'.
The others look good to me, too.

[harawata]

It's been a while, so I assume that everyone is OK with the reverse DNS naming rule. :)

@hazendaz ,
In the parent's pom.xml, there should be an entry configuring maven-jar-plugin.
For example,

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-jar-plugin</artifactId>
  <configuration>
    <archive>
      <manifestEntries>
        <Automatic-Module-Name>${module.name}</Automatic-Module-Name>
      </manifestEntries>
    </archive>
  </configuration>
</plugin>

And in each subproject, declare the property.

<properties>
  ...
  <module.name>org.mybatis</module.name>
  ...
</properties>