[FLINK-16995][table-common] Add new data structure interfaces in table-common

[wuchong]

What is the purpose of the change

This add the new data structure interfaces to table-common which has been discussed in FLIP-95.

The planner and connector refactoring will happen in a separate PR.

Brief change log

New interfaces and JavaDocs for all of them added.

Verifying this change

• All of them are interfaces except DecimalData and TimestampData, the corresponing tests will be moved to table-common when refactoring planner.

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): (yes / no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (yes / no)
• The serializers: (yes / no / don't know)
• The runtime per-record code paths (performance sensitive): (yes / no / don't know)
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: (yes / no / don't know)
• The S3 file system connector: (yes / no / don't know)

Documentation

• Does this pull request introduce a new feature? (yes / no)
• If yes, how is the feature documented? (not applicable / docs / JavaDocs / not documented)

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[JingsongLi]

Thanks @wuchong, yes, we can introduce formats again, but:

1. We will have two kind of formats in Flink repo in this time.
2. There are lots of the preparation work is waiting for us to do.
3. I am not sure these formats can work in planner 100%.

Another way is:

1. Preparation for decimal, modify decimal structure.
2. Preparation for string, modify string structure.
3. Preparation for Array, modify Array structure.
   .....

Just a suggestion.

[wuchong]

Hi @JingsongLi , I would prefer to refactor all of them together, not one by one. This will reduce the refactor work and review work.

We will have two kind of formats in Flink repo in this time.

We will have a follow up refactor PR soon. This situation will not last long.

I am not sure these formats can work in planner 100%.

This is on purpose to split the interface and refactoring into separete PRs. This PR just focuses on the user-facing APIs and Javadocs, to keep align with FLIP-95 proposal. So more people who care API can join in the reviewing. The following-up PR should focus on making planner 100% work on this new structures.

[wuchong]

Rebased and added GenericRowData, GenericMapData, GenericArrayData because they are all public APIs proposed in FLIP-95.

[twalthr]

Thanks for the PR @wuchong. I was writing a lot of JavaDocs in the last days and tried to also further improve them for the data structures. I push a commit to this branch. In particular it tries to:

• fix typos and grammar mistakes
• nicely format the JavaDocs
• cross reference classes for improve the experience for new users
• explain nullability and immutability everywhere

If you don't like certain changes, feel free to undo them again.

[wuchong]

Thanks @twalthr for helping to improve the Javadoc. All of them looks good to me.
I only removed "This data structure is immutable" from Javadoc of StringData.

If you don't have any other concens, I would like to merge this then.

[wuchong]

BinaryStringData is mutable, because it is lazy (de)serialized. The binary is lazily materialized when needed, so it's not thread-safe.

[twalthr]

@wuchong What I meant with immutable is that it does not provide any setters. Because GenericRowData has setters. But I'm fine with removing it here.

[twalthr]

LGTM

[JingsongLi]

Hi @wuchong , this is a wrong implementation here. Can you take https://issues.apache.org/jira/browse/FLINK-16922 and fix that?

[wuchong]

OK. Will do that in FLINK-16996.