eeverman
Getting rid of the 'no module descriptor' error in Maven builds
This error is primarily caused with Maven currently being unable to work with Java 9+ 's module system.
Here's an interesting write up about it by Maven Guru Robert Scholte
The main changes as part of this MR are as follows:
- andhow-annoitation-processor maven-compiler-plugin targeting Java 9
- Added an additional option to generate javadoc in HTML 5 to get rid of a lengthy warning about future migrations
- Added Java 9+ module-info to supply module descriptors to Maven
- BONUS "The POM for com.sun:tools:jar:___:1.8 is missing, no dependency information available" x2 also eliminated by Modular build
- maven-enforcer-plugin max Java version increased to <11 from <1.9
This ensures that the output from maven-javadoc-plugin reduced from
[INFO]
[INFO] --- maven-javadoc-plugin:3.0.1:jar (javadoc-jar) @ andhow ---
[WARNING] The POM for com.sun:tools:jar:sources:1.8 is missing, no dependency information available
[WARNING] The POM for com.sun:tools:jar:javadoc-resources:1.8 is missing, no dependency information available
[ERROR] no module descriptor for org.yarnandtail:andhow
[ERROR] no module descriptor for org.yarnandtail:andhow-core
[ERROR] no module descriptor for org.yarnandtail:andhow-annotation-processor
[INFO] The goal 'org.apache.maven.plugins:maven-javadoc-plugin:3.0.1:javadoc' has not been previously called for the module: 'org.yarnandtail:andhow-core:jar:0.4.1-SNAPSHOT'. Trying to invoke it...
[WARN] Maven will be executed in interactive mode, but no input stream has been configured for this MavenInvoker instance.
[WARNING] Creating fake javadoc directory to prevent repeated invocations: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-core\target\apidocs
[INFO] The goal 'org.apache.maven.plugins:maven-javadoc-plugin:3.0.1:javadoc' has not been previously called for the module: 'org.yarnandtail:andhow-annotation-processor:jar:0.4.1-SNAPSHOT'. Trying to invoke it...
[WARN] Maven will be executed in interactive mode, but no input stream has been configured for this MavenInvoker instance.
[ERROR] MavenInvocationException: Error when invoking Maven, consult the invoker log file: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow\target\invoker\maven-javadoc-plugin410922879.txt
[WARNING] Creating fake javadoc directory to prevent repeated invocations: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-annotation-processor\target\apidocs
[ERROR] Error fetching link: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-core\target\apidocs/package-list. Ignored it.
[ERROR] Error fetching link: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-annotation-processor\target\apidocs/package-list. Ignored it.
[INFO]
1 warning
[WARNING] Javadoc Warnings
[WARNING] C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-annotation-processor\src\main\java\org\yarnandtail\andhow\compile\CompileUnit.java:153: warning - Tag @see: missing '#': "getInnerPathNames() for just the names of the nested inner classes."
[INFO] Building jar: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow\target\andhow-0.4.1-SNAPSHOT-javadoc.jar
[INFO]
[INFO] ------------------------------------------------------------------------
to
[INFO]
[INFO] --- maven-javadoc-plugin:3.0.1:jar (javadoc-jar) @ andhow ---
[INFO] The goal 'org.apache.maven.plugins:maven-javadoc-plugin:3.0.1:javadoc' has not been previously called for the module: 'org.yarnandtail:andhow-core:jar:0.4.1-SNAPSHOT'. Trying to invoke it...
[WARN] Maven will be executed in interactive mode, but no input stream has been configured for this MavenInvoker instance.
[WARNING] Creating fake javadoc directory to prevent repeated invocations: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-core\target\apidocs
[INFO] The goal 'org.apache.maven.plugins:maven-javadoc-plugin:3.0.1:javadoc' has not been previously called for the module: 'org.yarnandtail:andhow-annotation-processor:jar:0.4.1-SNAPSHOT'. Trying to invoke it...
[WARN] Maven will be executed in interactive mode, but no input stream has been configured for this MavenInvoker instance.
[ERROR] MavenInvocationException: Error when invoking Maven, consult the invoker log file: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow\target\invoker\maven-javadoc-plugin1808595626.txt
[WARNING] Creating fake javadoc directory to prevent repeated invocations: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-annotation-processor\target\apidocs
[ERROR] Error fetching link: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-core\target\apidocs/package-list. Ignored it.
[ERROR] Error fetching link: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow-annotation-processor\target\apidocs/package-list. Ignored it.
[INFO] Building jar: C:\Users\Titu\Source\github.com\code4t2\andhow\andhow\target\andhow-0.4.1-SNAPSHOT-javadoc.jar
[INFO]
[INFO] ----------------< org.yarnandtail:andhow-system-tests >-----------------
Must eliminate that one warning that keeps coming with JDK 8. Will probably raise a tiny MR to fix it later.
Fixes #448
Kindly review bearing in mind this means a (most likely irreversible) move to Java 9+
Oh no, looks like the CI build failed. Looking through its logs seems to suggest that it used JDK 1.8 - 191. This wouldn't work, of course. It needs JDK 9+
Tested on my PC with JDK 10.0.1 and Maven 3.5.4
Ah, I wouldn't have guessed those module errors are related to JDK9 modules. Maybe they added it as a warning in the newest versions of JDK8.
I cannot switch to JDK9 for this release, otherwise it will not work with projects running on JDK8. I have some discussion of this here.
I should create a roadmap page, but the milestone page has some details of release planning:
- 0.4.1 This is the release we are working toward now, which is focused on bug fixes and improved testing.
- 0.5.0 This will be some API changes and potentially break some compatibility, but will still be JDK8
- 0.6.0 This will be the switch to JDK9
Is there a portion of this PR that can be kept for 0.4.1, or does all of it belong in the 0.6.0 release?
Ah. Thanks for pointing out the page with the details of milestones. This helps a lot. It's been ages since I looked around GitHub. I mainly use GitLab personally and at work. Will go through the site in detail later today.
No, @eeverman . I do not think any part of #448 can be retained for anything pre-0.6.0 . Every line in there is focused around the single issue, which is also why I had to raise a PR for the single # that removed the last javadoc warning.
On the bright side, unless the package names change #448 could go into 0.6.0 without throwing up any conflicts. It could even be one of the first commits (pending review around JDK9+ module system changes)