Improve test reliability by resolving nondeterministic of HashMap

[MyEnthusiastic]

Problem

I detected the unstable For the test :

[INFO] org.apache.tez.dag.api.TestDAG#testRecreateDAG
[INFO] org.apache.tez.dag.api.TestDAGPlan#userVertexOrderingIsMaintained

(they both use verify and createDag function and will be affected by the order of the vertex map)

[INFO] org.apache.tez.dag.app.dag.impl.TestVertexImpl#testVertexInit

All these tests assume the order of the Map (but java provided one with ordered specification called LinkedHashMap). which was not true, and will trigger hidden bug when the test environment changes.

Solution

we used the order-specified one which is LinkedHashMap because the order does matter for the tests (and potential future tests especially because the serialization)

Do no worry too much about the performance because these tests was detected mainly because they will be used by iteration (and the order is un defined), the iteration have better performance for LinkedHashMap: https://stackoverflow.com/questions/12998568/hashmap-vs-linkedhashmap-performance-in-iteration-over-values

Reproduce

This error can be reproduced with the NondexTool with the following command (you can try that without modifying the pom, but feel free to use the plugin to protect your project and make it safer 😊 ), and this kind problem is widely documented in International Dataset of Flaky Tests (IDoFT)

mvn edu.illinois:nondex-maven-plugin:2.1.7-SNAPSHOT:nondex -pl ./wicket-core-tests -DnondexRuns=10 -Dtest=org.apache.wicket.markup.html.form.CollectionFormComponentTest#getSetUnmodifiableSet

[tez-yetus]

🎊 +1 overall

Vote	Subsystem	Runtime	Comment
+0 🆗	reexec	24m 52s	Docker mode activated.
		_ Prechecks _
+1 💚	dupname	0m 0s	No case conflicting files found.
+1 💚	@author	0m 0s	The patch does not contain any @author tags.
+1 💚	test4tests	0m 0s	The patch appears to include 1 new or modified test files.
		_ master Compile Tests _
+0 🆗	mvndep	6m 27s	Maven dependency ordering for branch
+1 💚	mvninstall	13m 28s	master passed
+1 💚	compile	1m 19s	master passed with JDK Ubuntu-11.0.20.1+1-post-Ubuntu-0ubuntu122.04
+1 💚	compile	1m 10s	master passed with JDK Private Build-1.8.0_382-8u382-ga-1~22.04.1-b05
+1 💚	checkstyle	1m 25s	master passed
+1 💚	javadoc	1m 13s	master passed with JDK Ubuntu-11.0.20.1+1-post-Ubuntu-0ubuntu122.04
+1 💚	javadoc	0m 57s	master passed with JDK Private Build-1.8.0_382-8u382-ga-1~22.04.1-b05
+0 🆗	spotbugs	1m 19s	Used deprecated FindBugs config; considering switching to SpotBugs.
+1 💚	findbugs	3m 3s	master passed
		_ Patch Compile Tests _
+0 🆗	mvndep	0m 9s	Maven dependency ordering for patch
+1 💚	mvninstall	0m 48s	the patch passed
+1 💚	compile	0m 54s	the patch passed with JDK Ubuntu-11.0.20.1+1-post-Ubuntu-0ubuntu122.04
+1 💚	javac	0m 54s	the patch passed
+1 💚	compile	0m 46s	the patch passed with JDK Private Build-1.8.0_382-8u382-ga-1~22.04.1-b05
+1 💚	javac	0m 46s	the patch passed
+1 💚	checkstyle	0m 34s	the patch passed
+1 💚	whitespace	0m 0s	The patch has no whitespace issues.
+1 💚	javadoc	0m 34s	the patch passed with JDK Ubuntu-11.0.20.1+1-post-Ubuntu-0ubuntu122.04
+1 💚	javadoc	0m 35s	the patch passed with JDK Private Build-1.8.0_382-8u382-ga-1~22.04.1-b05
+1 💚	findbugs	2m 15s	the patch passed
		_ Other Tests _
+1 💚	unit	2m 13s	tez-api in the patch passed.
+1 💚	unit	4m 55s	tez-dag in the patch passed.
+1 💚	asflicense	0m 24s	The patch does not generate ASF License warnings.
		69m 17s

Subsystem	Report/Notes
Docker	ClientAPI=1.43 ServerAPI=1.43 base: https://ci-hadoop.apache.org/job/tez-multibranch/job/PR-316/1/artifact/out/Dockerfile
GITHUB PR	#316
Optional Tests	dupname asflicense javac javadoc unit spotbugs findbugs checkstyle compile
uname	Linux 17c0b8fccbce 5.15.0-88-generic #98-Ubuntu SMP Mon Oct 2 15:18:56 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	personality/tez.sh
git revision	master / 51d6f53
Default Java	Private Build-1.8.0_382-8u382-ga-1~22.04.1-b05
Multi-JDK versions	/usr/lib/jvm/java-11-openjdk-amd64:Ubuntu-11.0.20.1+1-post-Ubuntu-0ubuntu122.04 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_382-8u382-ga-1~22.04.1-b05
Test Results	https://ci-hadoop.apache.org/job/tez-multibranch/job/PR-316/1/testReport/
Max. process+thread count	461 (vs. ulimit of 5500)
modules	C: tez-api tez-dag U: .
Console output	https://ci-hadoop.apache.org/job/tez-multibranch/job/PR-316/1/console
versions	git=2.34.1 maven=3.6.3 findbugs=3.0.1
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