opened
HyukjinKwon
### What changes were proposed in this pull request?

This PR proposes to clean up `UnivocityParser`. 

### Why are the changes needed?

It will slightly improve the performance since we don't do unnecessary computation for Array concatenations/creation.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

Manually ran the existing tests.
[SPARK-30530][SQL][FOLLOW-UP] Remove unnecessary codes and fix comments accordingly in UnivocityParser
issue
created
HyukjinKwon
cc @cloud-fan and @MaxGekk. It's rather minor but wanted to clean up here.
comment
created
HyukjinKwon
retest this please
comment
created
HyukjinKwon
retest this please
comment
created
MaxGekk
Something wrong is going on. This exception shouldn't happen:
```
Caused by: java.lang.IllegalStateException: Number of logging event reached the limit: 100
	at org.apache.spark.SparkFunSuite$LogAppender.append(SparkFunSuite.scala:197)
	at org.apache.log4j.AppenderSkeleton.doAppend(AppenderSkeleton.java:251)
```
It was added by https://github.com/apache/spark/pull/27166, and the limit shouldn't be reachable.
comment
created
MaxGekk
I propose to assign names to log appenders, and print the names in exception. So, we will know which one wasn't removed.
comment
created
srowen
Jenkins, retest this please
comment
created
HyukjinKwon
Merged to master.
comment
**[Test build #117097 has started](https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/117097/testReport)** for PR 27287 at commit [`c2c5ab0`](https://github.com/apache/spark/commit/c2c5ab02475eff2105ab6bee2b93f3fc2eee693c).
This message directly preceded comment from bot *SparkQA* by author *HyukjinKwon*:
retest this please
**[Test build #117121 has started](https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/117121/testReport)** for PR 27287 at commit [`c2c5ab0`](https://github.com/apache/spark/commit/c2c5ab02475eff2105ab6bee2b93f3fc2eee693c).
This message directly preceded comment from bot *SparkQA* by author *HyukjinKwon*:
retest this please
**[Test build #117124 has started](https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/117124/testReport)** for PR 27287 at commit [`c2c5ab0`](https://github.com/apache/spark/commit/c2c5ab02475eff2105ab6bee2b93f3fc2eee693c).
This message directly preceded comment from bot *SparkQA* by author *srowen*:
Jenkins, retest this please
This message directly preceded comment from bot *SparkQA* by author *HyukjinKwon*:
retest this please
This message directly preceded comment from bot *SparkQA* by author *HyukjinKwon*:
retest this please
This message directly preceded comment from bot *SparkQA* by author *srowen*:
Jenkins, retest this please