[GROOVY-8339] Fix warning "An illegal reflective access operation has occurred"

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.4.11, 2.4.15
• Fix Version/s: 3.0.0-beta-1
• Component/s: groovy-jdk
• Labels: security

Environment

>gradle --version
Gradle 4.2
Build time: 2017-09-20 14:48:23 UTC
Revision: 5ba503cc17748671c83ce35d7da1cffd6e24dfbd

Groovy: 2.4.11
Ant: Apache Ant(TM) version 1.9.6 compiled on June 29 2015
JVM: 9 (Oracle Corporation 9+181)
OS: Windows 10 10.0 amd64

• Assignee: Daniel Sun
• Reporter: Benjamin Roedell
• Created: 02/Oct/17 15:45
• Updated: 20/May/19 07:31
• Resolved: 01/May/19 12:36

Description

I'm running JDK-9 on Windows 10 with Gradle 4.2.

My global gradle.properties file contains the following line:
org.gradle.java.home=C:/Program Files/Java/jdk-9

When I request the gradle version (gradle --version) I get the following warning:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.codehaus.groovy.reflection.CachedClass (file:/C:/Program%20Files/gradle-4.2/lib/groovy-all-2.4.11.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 warning displayed regardless of whether I'm using a regular command prompt or an elevated rights (Administrator) command prompt.

Here's the full command and output:

gradle --version
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.codehaus.groovy.reflection.CachedClass (file:/C:/Program%20Files/gradle-4.2/lib/groovy-all-2.4.11.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

------------------------------------------------------------
Gradle 4.2
------------------------------------------------------------

Build time:   2017-09-20 14:48:23 UTC
Revision:     5ba503cc17748671c83ce35d7da1cffd6e24dfbd

Groovy:       2.4.11
Ant:          Apache Ant(TM) version 1.9.6 compiled on June 29 2015
JVM:          9 (Oracle Corporation 9+181)
OS:           Windows 10 10.0 amd64

Issue Links

• is cloned by: GROOVY-9081 CLONE - Fix warning "An illegal reflective access operation has occurred"
• is duplicated by: GROOVY-8396 illegal reflective access
• is duplicated by: GROOVY-8918 Illegal Reflective Access reported during Gradle build
• is duplicated by: GROOVY-9066 An illegal reflective access operation has occurred - on groovysh / Groovy 3.0.0-alpha-4 on Win 10 with JDK 11 (all 64 bit)
• is duplicated by: GROOVY-9070 OpenJdk 11 Illegal reflective access
• is duplicated by: GROOVY-8958 Groovy binary 3.0 alpha 4 gives illegal exception
• links to: GitHub Pull Request #905
• links to: GitHub Pull Request #919