1.19.0 version > Warning during library use in JUnit 4 about illegal access operations

[olivierlemee]

Hello, when we use the library for environment variable into a JUnit 4 (4.13.2 version) test case, a warning log is thrown as:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.junit.contrib.java.lang.system.EnvironmentVariables (file:/Users/olivier/.m2/repository/com/github/stefanbirkner/system-rules/1.19.0/system-rules-1.19.0.jar) to field java.util.Collections$UnmodifiableMap.m
WARNING: Please consider reporting this to the maintainers of org.junit.contrib.java.lang.system.EnvironmentVariables
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

[souravs17031999]

@olivierlemee I am having same issues , any resolution or fix you got ?

[bpcw]

It seems that 1.19.0 is not compatible with newer JDKs. We are trying to upgrade to JDK 17 and we also get this error in our JUnit 4 tests.

java.lang.reflect.InaccessibleObjectException: Unable to make field private final java.util.Map java.util.Collections$UnmodifiableMap.m accessible: module java.base does not "opens java.util" to unnamed module @1c2c22f3
	at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
	at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
	at java.base/java.lang.reflect.Field.checkCanSetAccessible(Field.java:178)
	at java.base/java.lang.reflect.Field.setAccessible(Field.java:172)
	at org.junit.contrib.java.lang.system.EnvironmentVariables.getFieldValue(EnvironmentVariables.java:188)
	at org.junit.contrib.java.lang.system.EnvironmentVariables.getEditableMapOfVariables(EnvironmentVariables.java:150)
	at org.junit.contrib.java.lang.system.EnvironmentVariables.access$200(EnvironmentVariables.java:49)
	at org.junit.contrib.java.lang.system.EnvironmentVariables$EnvironmentVariablesStatement.restoreOriginalVariables(EnvironmentVariables.java:134)
	at org.junit.contrib.java.lang.system.EnvironmentVariables$EnvironmentVariablesStatement.evaluate(EnvironmentVariables.java:125)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
	at org.junit.runners.BlockJUnit4ClassRunner$1.evaluate(BlockJUnit4ClassRunner.java:100)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:63)
	at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
	at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:93)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:40)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:529)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:756)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:452)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:210)

Are there any plans to bring this quite useful library up to work with newer JDKs?

[ashleyfrieze]

There's a fix - https://www.baeldung.com/java-unit-testing-environment-variables#3-when-reflective-access-doesnt-work

[twistedpair]

This is also blocking JVM version upgrading for me.

Here's a quick work around if you're using Gradle, but surely the JVM devs have a recommended work around going forward for the Java APIs.

test {
    // Allow com.github.stefanbirkner:system-rules to work until the Java 17+ support is fixed - https://github.com/stefanbirkner/system-rules/issues/87
    jvmArgs ('--add-opens', 'java.base/java.util=ALL-UNNAMED', '--add-opens', 'java.base/java.lang=ALL-UNNAMED')
}

[nagkumar]

yes, more modern of this lib is

https://github.com/stefanbirkner/system-lambda

Now system-lambda is also obsolete, the next modern one is

https://github.com/tginsberg/junit5-system-exit, however this works till jdk 24 as of today not in jdk 24.