ARROW-3171: [Java] Enable checkstyle for line length and indentation

[BryanCutler]

This change enables checkstyle line length set at 120 columns and indentation checks.

[BryanCutler]

I'm not sure if this specific style of indentation is enforced by our checkstyle, but wanted to bring it up in case others had different preferences.

[jacques-n]

I prefer this format. FYI I believe intellij does a different one where arguments hang off the opening parenthesis but I much prefer this pattern. +1 on enforcing it.

[BryanCutler]

Sounds good, I'll try to see if I can figure out how to enforce it. It's hard to tell right now because there are so many other warnings.

[jacques-n]

I vote for 140 or 160. 100 is so short on these widescreens.

[BryanCutler]

cc @icexelloss @jacques-n

[icexelloss]

Can you remind me why are we suppressing checks here?

[BryanCutler]

I'm suppressing all but the ones I have fixed so far, so I can do this incrementally. Eventually, this will be removed when the build passes all checks.

[BryanCutler]

I vote for 140 or 160. 100 is so short on these widescreens.

I'm fine with going above 100, although having it too long makes it hard to read. I would probably prefer 120, but I'm ok with 140. So +1 for 140. Any opinion on this @icexelloss ?

[icexelloss]

I am +1 for 120 but ok with 140 too.

[wesm]

FWIW In C++ we are 90 chars (Google limits to 80). But I guess Java devs mostly look at one file at a time? =)

[wesm]

https://google.github.io/styleguide/javaguide.html#s4.4-column-limit

[BryanCutler]

@jacques-n would you be ok with trying out 120 for the line length? It's always easier to make it bigger if it becomes too cumbersome

[jacques-n]

I'm okay with 120.

[BryanCutler]

Ok, I'm done with line length at 120 and indentation checks, please take another look - thanks!

[codecov-io]

Codecov Report

Merging #2512 into master will increase coverage by 1.15%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2512      +/-   ##
==========================================
+ Coverage   86.33%   87.49%   +1.15%     
==========================================
  Files         308      259      -49     
  Lines       47120    44797    -2323     
==========================================
- Hits        40682    39194    -1488     
+ Misses       6366     5603     -763     
+ Partials       72        0      -72

Impacted Files	Coverage Δ
go/arrow/datatype_nested.go
go/arrow/math/uint64_amd64.go
go/arrow/internal/testing/tools/bool.go
go/arrow/internal/bitutil/bitutil.go
go/arrow/memory/memory_avx2_amd64.go
go/arrow/array/null.go
go/arrow/math/uint64_avx2_amd64.go
go/arrow/array/builder.go
go/arrow/array/binary.go
go/arrow/array/numeric.gen.go
... and 39 more

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[BryanCutler]

ping @icexelloss @jacques-n , look ok to merge?

[jacques-n]

lgtm +1

[BryanCutler]

merged to master, thanks @jacques-n and @icexelloss !