RFR 8222936: mlvm/anonloader/stress/randomBytecodes/Test.java fails due to "ERROR: There were 1 hangups during parsing."

[Harold Seigel]

Hi,

Please review this fix for bug JDK-8222936.

Test .../randomBytecodes/Test.java uses StressClassLoadingTest.java to 
go through 1000's of iterations where it creates and starts a thread and 
waits 10 seconds.  The thread tries to load a class whose bytes are 
potentially randomized.  If the created thread is still alive after 10 
seconds then the test saves the randomized class and records a hang 
failure.  It then repeats the process for the next iteration.

This test fails about once a month with a hang failure.  These appear to 
be invalid failures because the hangs cannot be reproduced with the 
saved randomized class and because the stack traces of the hanging 
threads are empty.  Perhaps it just took more than 10 seconds for the 
thread to start because of lack of machine resources?

This change prevents the invalid failures by blocking the entire test 
until either the test fails with a timeout or the loading thread 
finishes, even if it takes more than 10 seconds.

Open Webrev: 
http://cr.openjdk.java.net/~hseigel/bug_8222936/webrev/index.html

JBS Bug: https://bugs.openjdk.java.net/browse/JDK-8222936

StressClassLoadingTest.java is used by three tests, 
.../randomBytecodes/Test.java, .../byteMutation/Test.java, and 
.../parallelLoad/Test.java.  The fix was tested by running the three 
tests one thousand times on Linux x64 and a few times on Solaris, 
Windows, and Mac OS X.

Thanks, Harold