ConcurrentModificationException in mutithread-looping client

[glassfishrobot]

the following code produces ConcurrentModificationException:

private static final int N_THREADS = Runtime.getRuntime().availableProcessors() * 2; private final ExecutorService executor = Executors.newFixedThreadPool(N_THREADS);

@Test public void testGrizzlyLite() throws InterruptedException {

final CountDownLatch cdl = new CountDownLatch(N_THREADS);

for (int i = 0; i < N_THREADS; i++) { executor.execute(new Runnable() { @Override public void run() { while (true) { try

{ FilterChainBuilder filterChain = FilterChainBuilder.stateless(); filterChain.add(new TransportFilter()); throw new IOException(filterChain.build() + "aa"); }

catch (IOException e) {

} } } }); } cdl.await(); }

Running org.dcache.xdr.GrizzlyBugTest Exception in thread "pool-1-thread-12" java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:901) at java.util.ArrayList$Itr.next(ArrayList.java:851) at org.glassfish.grizzly.filterchain.ListFacadeFilterChain.addAll(ListFacadeFilterChain.java:96) at org.glassfish.grizzly.filterchain.FilterChainBuilder$StatelessFilterChainBuilder.build(FilterChainBuilder.java:152) at org.dcache.xdr.GrizzlyBugTest$1.run(GrizzlyBugTest.java:41) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745)

This is triggered by GC calling AbstractFilterChain#finalize(); Somehow the list is still in use. I don;t know is it grizzly issue or JVM.

Neverhteless, there are no reasons why FilterChainBuilder uses DefaultFilterChain to keep list of defined filters. Changing it to regular ArrayList fixes the issue.

Regards, Tigran.

Environment

$ uname -a Linux ani 4.1.10-200.fc22.x86_64 #1 SMP Mon Oct 5 14:22:49 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux $ java -version openjdk version "1.8.0_60" OpenJDK Runtime Environment (build 1.8.0_60-b27) OpenJDK 64-Bit Server VM (build 25.60-b23, mixed mode)

Affected Versions

[2.3.22]

[glassfishrobot]

Reported by kofemann

[glassfishrobot]

kofemann said: fix: https://github.com/GrizzlyNIO/grizzly-mirror/pull/5 (why I cant attach patch ?)

[glassfishrobot]

@rlubke said: Because the j.net infrastructure has it disabled for all but project committers due to spam. Not a fan of it myself, but out of our control. Thanks for the pull request. Will review shortly.

[glassfishrobot]

@rlubke said: Changes applied: c33c038

No need to port to master.

[glassfishrobot]

This issue was imported from java.net JIRA GRIZZLY-1809

[glassfishrobot]

Marked as fixed on Thursday, October 15th 2015, 12:06:13 pm