DefaultThreadFactory must not use Thread.currentThread() when constru…

[normanmaurer]

…cted without ThreadGroup

Motivation:

We had a bug in out DefaulThreadFactory as it always retrieved the ThreadGroup to used during creation time when now explicit ThreadGroup was given. This is problematic as the Thread may die and so the ThreadGroup is destroyed even tho the DefaultThreadFactory is still used.

This could produce exceptions like:

java.lang.IllegalThreadStateException
at java.lang.ThreadGroup.addUnstarted(ThreadGroup.java:867)
at java.lang.Thread.init(Thread.java:405)
at java.lang.Thread.init(Thread.java:349)
at java.lang.Thread.(Thread.java:599)
at io.netty.util.concurrent.FastThreadLocalThread.(FastThreadLocalThread.java:60)
at io.netty.util.concurrent.DefaultThreadFactory.newThread(DefaultThreadFactory.java:122)
at io.netty.util.concurrent.DefaultThreadFactory.newThread(DefaultThreadFactory.java:106)
at io.netty.util.concurrent.ThreadPerTaskExecutor.execute(ThreadPerTaskExecutor.java:32)
at io.netty.util.internal.ThreadExecutorMap$1.execute(ThreadExecutorMap.java:57)
at io.netty.util.concurrent.SingleThreadEventExecutor.doStartThread(SingleThreadEventExecutor.java:978)
at io.netty.util.concurrent.SingleThreadEventExecutor.startThread(SingleThreadEventExecutor.java:947)
at io.netty.util.concurrent.SingleThreadEventExecutor.execute(SingleThreadEventExecutor.java:830)
at io.netty.util.concurrent.SingleThreadEventExecutor.execute(SingleThreadEventExecutor.java:818)
at io.netty.channel.AbstractChannel$AbstractUnsafe.register(AbstractChannel.java:471)
at io.netty.channel.SingleThreadEventLoop.register(SingleThreadEventLoop.java:87)
at io.netty.channel.SingleThreadEventLoop.register(SingleThreadEventLoop.java:81)
at io.netty.channel.MultithreadEventLoopGroup.register(MultithreadEventLoopGroup.java:86)
at io.netty.bootstrap.AbstractBootstrap.initAndRegister(AbstractBootstrap.java:323)
at io.netty.bootstrap.AbstractBootstrap.doBind(AbstractBootstrap.java:272)
at io.netty.bootstrap.AbstractBootstrap.bind(AbstractBootstrap.java:239)
at io.netty.incubator.codec.quic.QuicTestUtils.newServer(QuicTestUtils.java:138)
at io.netty.incubator.codec.quic.QuicTestUtils.newServer(QuicTestUtils.java:143)
at io.netty.incubator.codec.quic.QuicTestUtils.newServer(QuicTestUtils.java:147)
at io.netty.incubator.codec.quic.QuicStreamFrameTest.testCloseHalfClosure(QuicStreamFrameTest.java:48)
at io.netty.incubator.codec.quic.QuicStreamFrameTest.testCloseHalfClosureUnidirectional(QuicStreamFrameTest.java:35)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:288)
at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:282)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.lang.Thread.run(Thread.java:748)

Modifications:

• If the user dont specify a ThreadGroup we will just pass null to the constructor of FastThreadLocalThread and so let it retrieve on creation time
• Adjust tests

Result:

Don't risk to see IllegalThreadStateExceptions.

[normanmaurer]

This problem did show up sometimes on the CI and so let the jobs fail.

[franz1981]

LGTM