如何让 JUnit5 与 JDK10（拼图）和 Maven3 一起工作？

Question

I work with some friends on a jdk 10 application which use the jigsaw feature set (introduced in jdk9) and junit5 with maven as build-management.

But always if we try to run tests with Maven we get a InaccessibleObjectException exception like:

[ERROR] resourceSchedule  Time elapsed: 0.001 s  <<< ERROR!
java.lang.reflect.InaccessibleObjectException: Unable to make de.truncated.framework.shared.resources.ResourceManagerTest() accessible: module de.truncated.framework.shared does not "opens de.truncated.framework.shared.resources" to unnamed module @ed7f8b4

I'm googling since days now ... in jdk9 it can be simply adressed with --permit-illegal-access but this it not possible in jdk10 because this flag was removed. And the jdk10 code examples from junit5 and others on github don't use jigsaw how it seems.

So it looks like I miss something major in the maven, module or jvm args config. It would be very nice if someone could provide help on this matter.

Thank you very much!

Some additional informations to the project which could be helpful:

• the primary code is configured by a module info file which exports (not opens) to everyone (its a framework like code base)
• the test code is not modularized
• no jvm args are applied currently

used versions:

<properties>
   <java.version>10</java.version>
   <maven.compiler.version>3.7.0</maven.compiler.version>
   <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
   <surefire.version>2.21.0</surefire.version>
   <asm.version>6.1.1</asm.version>
   <junit.jupiter.version>5.2.0</junit.jupiter.version>
   <junit.platform.version>1.2.0</junit.platform.version>
</properties>

depencies:

    <!--
    junit 5 dependency
    -->
    <dependency>
        <groupId>org.junit.platform</groupId>
        <artifactId>junit-platform-launcher</artifactId>
        <version>${junit.platform.version}</version>
        <scope>test</scope>
    </dependency>

    <dependency>
        <groupId>org.junit.jupiter</groupId>
        <artifactId>junit-jupiter-api</artifactId>
        <version>${junit.jupiter.version}</version>
        <scope>test</scope>
    </dependency>

    <dependency>
        <groupId>org.junit.jupiter</groupId>
        <artifactId>junit-jupiter-engine</artifactId>
        <version>${junit.jupiter.version}</version>
        <scope>test</scope>
    </dependency>

build plugins:

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>${maven.compiler.version}</version>
            <configuration>
                <source>${java.version}</source>
                <target>${java.version}</target>
                <verbose>true</verbose>
            </configuration>
            <dependencies>
                <dependency>
                    <groupId>org.ow2.asm</groupId>
                    <artifactId>asm</artifactId>
                    <version>${asm.version}</version>
                </dependency>
            </dependencies>
        </plugin>
        <plugin>
            <artifactId>maven-surefire-plugin</artifactId>
            <version>${surefire.version}</version>
            <dependencies>
                <dependency>
                    <groupId>org.junit.platform</groupId>
                    <artifactId>junit-platform-surefire-provider</artifactId>
                    <version>${junit.platform.version}</version>
                </dependency>
                <dependency>
                    <groupId>org.ow2.asm</groupId>
                    <artifactId>asm</artifactId>
                    <version>${asm.version}</version>
                </dependency>
            </dependencies>
        </plugin>
    </plugins>
</build>

full stacktrace:

[INFO] Running de.truncated.framework.shared.resources.ResourceManagerTest
[ERROR] Tests run: 2, Failures: 0, Errors: 2, Skipped: 0, Time elapsed: 0 s <<< FAILURE! - in de.truncated.framework.shared.resources.ResourceManagerTest
[ERROR] singleThreadedResource  Time elapsed: 0 s  <<< ERROR!
java.lang.reflect.InaccessibleObjectException: Unable to make de.truncated.framework.shared.resources.ResourceManagerTest() accessible: module de.truncated.framework.shared does not "opens de.truncated.framework.shared.resources" to unnamed module @3af9c5b7
    at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:337)
    at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:281)
    at java.base/java.lang.reflect.Constructor.checkCanSetAccessible(Constructor.java:192)
    at java.base/java.lang.reflect.Constructor.setAccessible(Constructor.java:185)
    at org.junit.platform.commons.util.ReflectionUtils.makeAccessible(ReflectionUtils.java:1332)
    at org.junit.platform.commons.util.ReflectionUtils.newInstance(ReflectionUtils.java:429)
    at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:60)
    at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.instantiateTestClass(ClassTestDescriptor.java:208)
    at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.instantiateAndPostProcessTestInstance(ClassTestDescriptor.java:195)
    at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$testInstanceProvider$0(ClassTestDescriptor.java:185)
    at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$testInstanceProvider$1(ClassTestDescriptor.java:189)
    at java.base/java.util.Optional.orElseGet(Optional.java:358)
    at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$testInstanceProvider$2(ClassTestDescriptor.java:188)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:81)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:58)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.prepare(HierarchicalTestExecutor.java:89)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.execute(HierarchicalTestExecutor.java:74)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.lambda$executeRecursively$2(HierarchicalTestExecutor.java:121)
    at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
    at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
    at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133)
    at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
    at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
    at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
    at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
    at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.lambda$executeRecursively$3(HierarchicalTestExecutor.java:121)
    at org.junit.platform.engine.support.hierarchical.SingleTestExecutor.executeSafely(SingleTestExecutor.java:66)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.executeRecursively(HierarchicalTestExecutor.java:108)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.execute(HierarchicalTestExecutor.java:79)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.lambda$executeRecursively$2(HierarchicalTestExecutor.java:121)
    at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
    at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
    at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133)
    at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
    at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
    at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
    at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
    at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.lambda$executeRecursively$3(HierarchicalTestExecutor.java:121)
    at org.junit.platform.engine.support.hierarchical.SingleTestExecutor.executeSafely(SingleTestExecutor.java:66)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.executeRecursively(HierarchicalTestExecutor.java:108)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor$NodeExecutor.execute(HierarchicalTestExecutor.java:79)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:55)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:43)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:170)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:154)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:90)
    at org.junit.platform.surefire.provider.JUnitPlatformProvider.invokeAllTests(JUnitPlatformProvider.java:132)
    at org.junit.platform.surefire.provider.JUnitPlatformProvider.invoke(JUnitPlatformProvider.java:111)
    at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:379)
    at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:340)
    at org.apache.maven.surefire.booter.ForkedBooter.execute(ForkedBooter.java:125)
    at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:413)

Answer 1

Today I've found two solutions for that issue.

1) You may add --add-opens to surefire plugin config:

<plugin>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>3.0.0-M1</version>
    <configuration>
        <argLine>--add-opens de.truncated.framework.shared/de.truncated.framework.shared.resources=ALL-UNNAMED</argLine>
    </configuration>
</plugin>

That will work because by default surefire plugin adds --add-reads to surefireargs file and JUnit5 uses reflection for which "reads" is not enough.

2) Alternatively you may mark all your JUnit5 test classes (and their annotated methods) as public . That will also help because in that case JUnit will not use reflection when running tests (well, at least it doesn't in version 5.3.1).

PS I used maven-compiler-plugin version 3.8.0 and maven-surefire-plugin 3.0.0-M1.

Answer 2

There is a (new) option in the Maven Surefire plugin called useModulePath . This option enables to use the traditional Java 8 class path instead of the module path and ignores a module-info.class not turning on the Java module mode, ie all class on the calls path can be used.

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>3.0.0-M5</version>
    <configuration>
        <!--  allow to use unnamed modules -->
        <useModulePath>false</useModulePath>
    </configuration>
</plugin>