tools/jdeps/modules/GenModuleInfo.java
tools/jdeps/modules/ModuleTest.java
(from langtools/test)

Recently observed these test failed intermittently:

----------System.out:(72/5460)----------
[TestNG] Running:
  tools/jdeps/modules/GenModuleInfo.java

config GenModuleInfo.compileAll(): success
test GenModuleInfo.jdeps(): success
test GenModuleInfo.test(): failure
java.lang.Error: java.util.concurrent.ExecutionException: java.lang.ClassCastException: java.util.HashMap$Node (in module: java.base) cannot be cast to java.util.HashMap$TreeNode (in module: java.base)
at com.sun.tools.jdeps.DependencyFinder$TaskExecutor.waitForTasksCompleted(jdk.jdeps@9-internal/DependencyFinder.java:361)
at com.sun.tools.jdeps.DependencyFinder.findDependencies(jdk.jdeps@9-internal/DependencyFinder.java:182)
at com.sun.tools.jdeps.ModuleInfoBuilder.run(jdk.jdeps@9-internal/ModuleInfoBuilder.java:85)
at com.sun.tools.jdeps.JdepsTask.genModuleInfo(jdk.jdeps@9-internal/JdepsTask.java:623)
at com.sun.tools.jdeps.JdepsTask.run(jdk.jdeps@9-internal/JdepsTask.java:445)
at com.sun.tools.jdeps.JdepsTask.run(jdk.jdeps@9-internal/JdepsTask.java:409)
at com.sun.tools.jdeps.Main.run(jdk.jdeps@9-internal/Main.java:63)
at GenModuleInfo.jdeps(GenModuleInfo.java:199)
at GenModuleInfo.test(GenModuleInfo.java:112)
at sun.reflect.NativeMethodAccessorImpl.invoke0(java.base@9-internal/Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(java.base@9-internal/NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(java.base@9-internal/DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(java.base@9-internal/Method.java:531)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:84)
at org.testng.internal.Invoker.invokeMethod(Invoker.java:714)
at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:901)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1231)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:127)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:111)
at org.testng.TestRunner.privateRun(TestRunner.java:767)
at org.testng.TestRunner.run(TestRunner.java:617)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:334)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:329)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:291)
at org.testng.SuiteRunner.run(SuiteRunner.java:240)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1224)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1149)
at org.testng.TestNG.run(TestNG.java:1057)
at com.sun.javatest.regtest.TestNGAction$TestNGRunner.main(TestNGAction.java:220)
at sun.reflect.NativeMethodAccessorImpl.invoke0(java.base@9-internal/Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(java.base@9-internal/NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(java.base@9-internal/DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(java.base@9-internal/Method.java:531)
at com.sun.javatest.regtest.agent.MainActionHelper$SameVMRunnable.run(MainActionHelper.java:226)
at java.lang.Thread.run(java.base@9-internal/Thread.java:804)
Caused by: java.util.concurrent.ExecutionException: java.lang.ClassCastException: java.util.HashMap$Node (in module: java.base) cannot be cast to java.util.HashMap$TreeNode (in module: java.base)
at java.util.concurrent.FutureTask.report(java.base@9-internal/FutureTask.java:123)
at java.util.concurrent.FutureTask.get(java.base@9-internal/FutureTask.java:193)
at com.sun.tools.jdeps.DependencyFinder$TaskExecutor.waitForTasksCompleted(jdk.jdeps@9-internal/DependencyFinder.java:358)
... 36 more
Caused by: java.lang.ClassCastException: java.util.HashMap$Node (in module: java.base) cannot be cast to java.util.HashMap$TreeNode (in module: java.base)
at java.util.HashMap$TreeNode.moveRootToFront(java.base@9-internal/HashMap.java:1879)
at java.util.HashMap$TreeNode.treeify(java.base@9-internal/HashMap.java:1996)
at java.util.HashMap.treeifyBin(java.base@9-internal/HashMap.java:771)
at java.util.HashMap.putVal(java.base@9-internal/HashMap.java:643)
at java.util.HashMap.put(java.base@9-internal/HashMap.java:611)
at com.sun.tools.classfile.Dependencies$BasicDependencyFinder.getLocation(jdk.jdeps@9-internal/Dependencies.java:569)
at com.sun.tools.classfile.Dependencies$BasicDependencyFinder$Visitor.<init>(jdk.jdeps@9-internal/Dependencies.java:581)
at com.sun.tools.classfile.Dependencies$ClassDependencyFinder.findDependencies(jdk.jdeps@9-internal/Dependencies.java:471)
at com.sun.tools.jdeps.DependencyFinder$TaskExecutor$1.call(jdk.jdeps@9-internal/DependencyFinder.java:310)
at com.sun.tools.jdeps.DependencyFinder$TaskExecutor$1.call(jdk.jdeps@9-internal/DependencyFinder.java:287)
at java.util.concurrent.FutureTask.run(java.base@9-internal/FutureTask.java:266)
at java.util.concurrent.Executors$RunnableAdapter.call(java.base@9-internal/Executors.java:514)
at java.util.concurrent.FutureTask.run(java.base@9-internal/FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(java.base@9-internal/ThreadPoolExecutor.java:1158)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(java.base@9-internal/ThreadPoolExecutor.java:632)
... 1 more

===============================================
tools/jdeps/modules/GenModuleInfo.java
Total tests run: 2, Failures: 1, Skips: 0
===============================================

----------System.err:(39/1960)----------
jdeps [-cp, libs/m1.jar, libs/m2.jar, libs/m3.jar, libs/unsupported.jar]
m2.jar -> java.base
m2.jar -> libs/m1.jar
   p2 (m2.jar)
      -> java.lang
      -> p1 m1.jar
   p2.internal (m2.jar)
      -> java.io
      -> java.lang
m3.jar -> java.base
m3.jar -> java.logging
m3.jar -> java.sql
m3.jar -> libs/m1.jar
m3.jar -> libs/m2.jar
   p3 (m3.jar)
      -> java.lang
      -> java.sql
      -> java.util.logging
      -> p1 m1.jar
      -> p2 m2.jar
      -> p2.internal m2.jar
unsupported.jar -> java.base
   q (unsupported.jar)
      -> java.lang
      -> jdk.internal.perf JDK internal API (java.base)

jdeps [-genmoduleinfo, moduleinfosrc, libs/m1.jar, libs/m2.jar, libs/m3.jar, libs/unsupported.jar]
java.lang.Exception: failures: 1
at com.sun.javatest.regtest.TestNGAction$TestNGRunner.main(TestNGAction.java:223)
at sun.reflect.NativeMethodAccessorImpl.invoke0(java.base@9-internal/Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(java.base@9-internal/NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(java.base@9-internal/DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(java.base@9-internal/Method.java:531)
at com.sun.javatest.regtest.agent.MainActionHelper$SameVMRunnable.run(MainActionHelper.java:226)
at java.lang.Thread.run(java.base@9-internal/Thread.java:804)