Bug#927056: groovy: Groovy gives warning with OpenJDK 11 about illegal reflective access

[Egon Willighagen]

Package: groovy
Version: 2.4.16-2
Severity: normal

Dear Maintainer,

with OpenJDK 11 (which seems to be the default in Buster) Groovy gives a warning at
start up time, for any Groovy script.

$ groovy -e "foo = \"Foo\""
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.codehaus.groovy.reflection.CachedClass (file:/usr/share/groovy/lib/groovy-2.4.16.jar) to method java.lang.Object.finalize()
WARNING: Please consider reporting this to the maintainers of org.codehaus.groovy.reflection.CachedClass
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

This is not the case with Java8 and may have to do with classes removed in Java11? Setting JAVA_HOME to have it use Java8 removes the warning.
The scripts do seem to run fine otherwise.

With kind regards,

Egon

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (1100, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.19.0-4-amd64 (SMP w/8 CPU cores)
Kernel taint flags: TAINT_CRAP, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=nl_NL.UTF-8, LC_CTYPE=nl_NL.UTF-8 (charmap=UTF-8), LANGUAGE=en_US (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages groovy depends on:
ii  antlr                                             2.7.7+dfsg-9.2
ii  default-jre-headless [java7-runtime-headless]     2:1.11-71
ii  ivy                                               2.4.0-5
ii  junit4                                            4.12-8
ii  libasm-java                                       7.0-1
ii  libbsf-java                                       1:2.4.0-8
ii  libcommons-cli-java                               1.4-1
ii  libcommons-logging-java                           1.2-2
ii  libjansi-java                                     1.17.1-1
ii  libjline2-java                                    2.14.6-3
ii  libqdox-java                                      1.12.1-3
ii  libservlet3.1-java [libservlet3.1-java]           1:4.0.1-2
ii  libxstream-java                                   1.4.11.1-1
ii  openjdk-10-jre-headless [java7-runtime-headless]  10.0.2+13-2
ii  openjdk-11-jre-headless [java7-runtime-headless]  11.0.3+1-1
ii  openjdk-8-jre-headless [java7-runtime-headless]   8u212-b01-1
ii  openjdk-9-jre-headless [java7-runtime-headless]   9~b181-4~bpo9+1

Versions of packages groovy recommends:
ii  ant                   1.10.5-2
ii  ant-optional          1.10.5-2
ii  libgpars-groovy-java  1.2.1-10
ii  libjcommander-java    1.71-3

Versions of packages groovy suggests:
pn  groovy-doc  <none>

-- no debconf information