guice compatibility with Java 9: "WARNING: Illegal reflective access by com.google.inject.internal."

[fcole90]

The `guice` version provided by maven seem not to be compatible with Java 9 as it throws the following warnings:

```
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.inject.internal.cglib.core.$ReflectUtils$1 (file:/usr/share/maven/lib/guice.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of com.google.inject.internal.cglib.core.$ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.inject.internal.cglib.core.$ReflectUtils$1 (file:/usr/share/maven/lib/guice.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of com.google.inject.internal.cglib.core.$ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
```

The related issue was already reported and resolved in upstream guice: https://github.com/google/guice/issues/1085

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: maven 3.5.2-2
ProcVersionSignature: Ubuntu 4.15.0-11.12-generic 4.15.5
Uname: Linux 4.15.0-11-generic x86_64
ApportVersion: 2.20.8-0ubuntu10
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Fri Mar 9 11:28:26 2018
InstallationDate: Installed on 2017-08-21 (199 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Alpha amd64 (20170820)
PackageArchitecture: all
SourcePackage: maven
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Aldric (picpic)]

Hello!

Same with jdk11 and maven 3.6.3.

➜ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04 LTS
Release: 20.04
Codename: focal

➜ mvn --version
Apache Maven 3.6.3
Maven home: /usr/share/maven
Java version: 11.0.7, vendor: Ubuntu, runtime: /usr/lib/jvm/java-11-openjdk-amd64
Default locale: en_GB, platform encoding: UTF-8
OS name: "linux", version: "5.4.0-33-generic", arch: "amd64", family: "unix"

➜ mvn clean
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.inject.internal.cglib.core.$ReflectUtils$1 (file:/usr/share/maven/lib/guice.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of com.google.inject.internal.cglib.core.$ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
[INFO] Scanning for projects...
[INFO]

Regards

[Bernt (bernt-hullen)]

Hallo,

It's the same error with Ubuntu 20.10

mvn --version
Apache Maven 3.6.3
Maven home: /usr/share/maven
Java version: 11.0.10, vendor: Ubuntu, runtime: /usr/lib/jvm/java-11-openjdk-amd64
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "5.8.0-44-generic", arch: "amd64", family: "unix"

[mjw99 (mark-williamson)]

Now seeing this manifest as an ERROR in JDK16 and Ubuntu 20.10:

$ java -version
openjdk version "16" 2021-03-16
OpenJDK Runtime Environment (build 16+36-2231)
OpenJDK 64-Bit Server VM (build 16+36-2231, mixed mode, sharing)

$ mvn clean test
[ERROR] Error executing Maven.
[ERROR] java.lang.IllegalStateException: Unable to load cache item
[ERROR] Caused by: Unable to load cache item
[ERROR] Caused by: Could not initialize class com.google.inject.internal.cglib.core.$MethodWrapper

This essentially breaks any CI that uses a 20.10 image with JDK16.

It might be worth looking at how the Debian people fixed this:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=980467

[Alexander Levsha (endeavourl)]

Is there any activity on this bug? Currently maven from this package is unusable when using latest Java 16.

[John Neffenger (jgneff)]

See also the following bug reported by Manuel J. on 2021-06-02:

Maven 3.6.3-1 fails to run with OpenJDK 16
https://bugs.launchpad.net/ubuntu/+source/maven/+bug/1930541

Perhaps this bug report should be marked as a duplicate of Bug #1930541 above, as the illegal reflective access is now an error with OpenJDK 16 instead of the prior warnings.

[Masanori Itoh (thatsdone)]

Hi, this issue looks like resolved at least the following conditions.

* Ubuntu 21.04 (nightly build at 20210917
* openjdk-16-jre-headless:amd64 16.0.1+9-1
* maven 3.6.3-5
* libguice-java 4.2.3-2

```
mitoh@mitoh-u2104a:~/test1$ mvn -version
Apache Maven 3.6.3
Maven home: /usr/share/maven
Java version: 16.0.1, vendor: Private Build, runtime: /usr/lib/jvm/java-16-openjdk-amd64
Default locale: en, platform encoding: UTF-8
OS name: "linux", version: "5.11.0-34-generic", arch: "amd64", family: "unix"
mitoh@mitoh-u2104a:~/test1$ ls
pom.xml src
mitoh@mitoh-u2104a:~/test1$ mvn clean
[INFO] Scanning for projects...
[INFO]
[INFO] -------------------------< com.example:test1 >--------------------------
[INFO] Building test1 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ test1 ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.150 s
[INFO] Finished at: 2021-09-26T01:02:39Z
[INFO] ------------------------------------------------------------------------
mitoh@mitoh-u2104a:~/test1$
```

For me, current problem is how to backport them to 20.04 LTS.