[SPARK-22072][SPARK-22071][BUILD]Improve release build scripts

[holdenk]

What changes were proposed in this pull request?

Check JDK version (with javac) and use SPARK_VERSION for publish-release

How was this patch tested?

Manually tried local build with wrong JDK / JAVA_HOME & built a local release (LFTP disabled)

[holdenk]

cc @JoshRosen

[SparkQA]

Test build #82048 has finished for PR 19312 at commit aa4cbf6.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[HyukjinKwon]

retest this please

[SparkQA]

Test build #82056 has finished for PR 19312 at commit aa4cbf6.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[HyukjinKwon]

@holdenk, should we maybe catch the case when JAVA_HOME is missing too?

If so, I think we could do something like ...

if [ -z"$JAVA_HOME" ];thenecho"Please set JAVA_HOME."exit 1
fi
...

Or maybe...

if [[ -x"$JAVA_HOME/bin/javac" ]];then
javac_cmd="$JAVA_HOME/bin/javac"else
javac_cmd=javac
fi
java_version=$("$javac_cmd" -version 2>&1| cut -d "" -f 2)
...

I tested both in my local.

[holdenk]

Thanks. The logic we use in make-distribution to resolve JAVA_HOME when not set is a bit more complicated, but I think for the release script its reasonable (and probably a good practice) to explicitly require a JAVA_HOME to be set so I'll go with the first of the 2.

[HyukjinKwon]

LGTM, just one comment

[SparkQA]

Test build #82071 has finished for PR 19312 at commit 94d7659.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[holdenk]

Merged to master, branch-2.2, and branch-2.1.