MAPREDUCE-7346. Fix divide by zero in AvgRecordFactory

[yiyuaner]

This commit fixes the issue here.

[hadoop-yetus]

💔 -1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	17m 15s		Docker mode activated.
			_ Prechecks _
+1 💚	dupname	0m 0s		No case conflicting files found.
+0 🆗	codespell	0m 1s		codespell was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
-1 ❌	test4tests	0m 0s		The patch doesn't appear to include any new or modified tests. Please justify why no new tests are needed for this patch. Also please list what manual steps were performed to verify this patch.
			_ trunk Compile Tests _
+1 💚	mvninstall	33m 5s		trunk passed
+1 💚	compile	0m 28s		trunk passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	compile	0m 25s		trunk passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	checkstyle	0m 21s		trunk passed
+1 💚	mvnsite	0m 29s		trunk passed
+1 💚	javadoc	0m 25s		trunk passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	javadoc	0m 22s		trunk passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	spotbugs	0m 46s		trunk passed
+1 💚	shadedclient	16m 17s		branch has no errors when building and testing our client artifacts.
			_ Patch Compile Tests _
+1 💚	mvninstall	0m 23s		the patch passed
+1 💚	compile	0m 22s		the patch passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	javac	0m 22s		the patch passed
+1 💚	compile	0m 19s		the patch passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	javac	0m 19s		the patch passed
-1 ❌	blanks	0m 0s	/blanks-eol.txt	The patch has 2 line(s) that end in blanks. Use git apply --whitespace=fix <<patch_file>>. Refer https://git-scm.com/docs/git-apply
-1 ❌	blanks	0m 0s	/blanks-tabs.txt	The patch 1 line(s) with tabs.
-0 ⚠️	checkstyle	0m 14s	/results-checkstyle-hadoop-tools_hadoop-gridmix.txt	hadoop-tools/hadoop-gridmix: The patch generated 1 new + 3 unchanged - 0 fixed = 4 total (was 3)
+1 💚	mvnsite	0m 22s		the patch passed
+1 💚	javadoc	0m 18s		the patch passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	javadoc	0m 16s		the patch passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	spotbugs	0m 48s		the patch passed
+1 💚	shadedclient	16m 25s		patch has no errors when building and testing our client artifacts.
			_ Other Tests _
+1 💚	unit	17m 15s		hadoop-gridmix in the patch passed.
+1 💚	asflicense	0m 30s		The patch does not generate ASF License warnings.
		108m 34s

Subsystem	Report/Notes
Docker	ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-3047/1/artifact/out/Dockerfile
GITHUB PR	#3047
Optional Tests	dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell
uname	Linux d5641ead0c6e 4.15.0-136-generic #140-Ubuntu SMP Thu Jan 28 05:20:47 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/bin/hadoop.sh
git revision	trunk / 6b8d7bbb20805e7ad4a0a35095efbcca3e956636
Default Java	Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
Multi-JDK versions	/usr/lib/jvm/java-11-openjdk-amd64:Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
Test Results	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-3047/1/testReport/
Max. process+thread count	975 (vs. ulimit of 5500)
modules	C: hadoop-tools/hadoop-gridmix U: hadoop-tools/hadoop-gridmix
Console output	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-3047/1/console
versions	git=2.25.1 maven=3.6.3 spotbugs=4.2.2
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[hadoop-yetus]

💔 -1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	0m 49s		Docker mode activated.
			_ Prechecks _
+1 💚	dupname	0m 0s		No case conflicting files found.
+0 🆗	codespell	0m 0s		codespell was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
-1 ❌	test4tests	0m 0s		The patch doesn't appear to include any new or modified tests. Please justify why no new tests are needed for this patch. Also please list what manual steps were performed to verify this patch.
			_ trunk Compile Tests _
+1 💚	mvninstall	34m 23s		trunk passed
+1 💚	compile	0m 30s		trunk passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	compile	0m 25s		trunk passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	checkstyle	0m 21s		trunk passed
+1 💚	mvnsite	0m 30s		trunk passed
+1 💚	javadoc	0m 24s		trunk passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	javadoc	0m 22s		trunk passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	spotbugs	0m 47s		trunk passed
+1 💚	shadedclient	16m 44s		branch has no errors when building and testing our client artifacts.
			_ Patch Compile Tests _
+1 💚	mvninstall	0m 24s		the patch passed
+1 💚	compile	0m 24s		the patch passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	javac	0m 24s		the patch passed
+1 💚	compile	0m 19s		the patch passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	javac	0m 19s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
+1 💚	checkstyle	0m 14s		the patch passed
+1 💚	mvnsite	0m 23s		the patch passed
+1 💚	javadoc	0m 18s		the patch passed with JDK Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04
+1 💚	javadoc	0m 16s		the patch passed with JDK Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
+1 💚	spotbugs	0m 49s		the patch passed
+1 💚	shadedclient	16m 26s		patch has no errors when building and testing our client artifacts.
			_ Other Tests _
+1 💚	unit	17m 38s		hadoop-gridmix in the patch passed.
+1 💚	asflicense	0m 31s		The patch does not generate ASF License warnings.
		94m 24s

Subsystem	Report/Notes
Docker	ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-3047/2/artifact/out/Dockerfile
GITHUB PR	#3047
Optional Tests	dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell
uname	Linux 57eba8cc8f8b 4.15.0-136-generic #140-Ubuntu SMP Thu Jan 28 05:20:47 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/bin/hadoop.sh
git revision	trunk / 77da40b
Default Java	Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
Multi-JDK versions	/usr/lib/jvm/java-11-openjdk-amd64:Ubuntu-11.0.11+9-Ubuntu-0ubuntu2.20.04 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_292-8u292-b10-0ubuntu1~20.04-b10
Test Results	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-3047/2/testReport/
Max. process+thread count	979 (vs. ulimit of 5500)
modules	C: hadoop-tools/hadoop-gridmix U: hadoop-tools/hadoop-gridmix
Console output	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-3047/2/console
versions	git=2.25.1 maven=3.6.3 spotbugs=4.2.2
Powered by	Apache Yetus 0.14.0-SNAPSHOT https://yetus.apache.org

This message was automatically generated.