Re: pgjdbc: Maven -> Gradle, Java 6 => 7, JUnit 4 => 5

>Most of these "Maven issues" can be fixed but of course it's not much fun
to figure out magic XML incantations to do so.

For those who vote "+-0 for Gradle", I would definitely recommend giving it
a try.
Even if you think "Maven is just enough", there's a broad (!) range of
cases when Gradle beats Maven.

---

Test output in Gradle is way easier to understand.
Gradle:
https://github.com/pgjdbc/pgjdbc/runs/484856356?check_suite_focus=true#step:5:218
Maven: https://travis-ci.org/github/pgjdbc/pgjdbc/jobs/658234574#L5913

Isn't that convincing?

Ok, here's another example:

$ maven checkstyle:check

Maven:
[INFO] --- maven-checkstyle-plugin:3.1.1:check (default-cli) @ postgresql
---
[INFO] Starting audit...
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:9: Import
statement for 'org.postgresql.copy.CopyManager' is in the wrong order.
Should be in the 'SAME_PACKAGE' group, expecting not assigned imports on
this line. [CustomImportOrder]
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:10:
Import statement for 'org.postgresql.fastpath.Fastpath' is in the wrong
order. Should be in the 'SAME_PACKAGE' group, expecting not assigned
imports on this line. [CustomImportOrder]
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:11:
Import statement for 'org.postgresql.jdbc.AutoSave' is in the wrong order.
Should be in the 'SAME_PACKAGE' group, expecting not assigned imports on
this line. [CustomImportOrder]
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:12:
Import statement for 'org.postgresql.jdbc.PreferQueryMode' is in the wrong
order. Should be in the 'SAME_PACKAGE' group, expecting not assigned
imports on this line. [CustomImportOrder]
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:13:
Import statement for 'org.postgresql.largeobject.LargeObjectManager' is in
the wrong order. Should be in the 'SAME_PACKAGE' group, expecting not
assigned imports on this line. [CustomImportOrder]
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:14:
Import statement for 'org.postgresql.replication.PGReplicationConnection'
is in the wrong order. Should be in the 'SAME_PACKAGE' group, expecting not
assigned imports on this line. [CustomImportOrder]
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:15:
Import statement for 'org.postgresql.util.PGobject' is in the wrong order.
Should be in the 'SAME_PACKAGE' group, expecting not assigned imports on
this line. [CustomImportOrder]
[ERROR] .../pgjdbc/src/main/java/org/postgresql/PGConnection.java:17: Extra
separation in import group before 'java.sql.SQLException'
[CustomImportOrder]
Audit done.
[INFO]
------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO]
------------------------------------------------------------------------
[INFO] Total time: 3.263 s
[INFO] Finished at: 2020-03-11T22:00:48+03:00
[INFO]
------------------------------------------------------------------------
[ERROR] Failed to execute goal
org.apache.maven.plugins:maven-checkstyle-plugin:3.1.1:check (default-cli)
on project postgresql: Failed during checkstyle execution: There are 8
errors reported by Checkstyle 8.29 with src/main/checkstyle/checks.xml
ruleset. -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e
switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions,
please read the following articles:
[ERROR] [Help 1]
http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

-----

$ ./gradlew check

> Task :postgresql:autostyleJavaCheck FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':postgresql:autostyleJavaCheck'.
> The following files have format violations:
pgjdbc/src/main/java/org/postgresql/PGConnection.java
@@ -5,7 +5,6 @@

package org.postgresql;

-import java.sql.Array;
import org.postgresql.copy.CopyManager;
import org.postgresql.fastpath.Fastpath;
import org.postgresql.jdbc.AutoSave;
@@ -14,6 +13,7 @@
import org.postgresql.replication.PGReplicationConnection;
import org.postgresql.util.PGobject;

+import java.sql.Array;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Map;
Run './gradlew autostyleApply' to fix the violations.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or
--debug option to get more log output. Run with --scan to get full insights.

Vladimir