[Java] Support concating vectors values in batch

[asfimport]

We need a way to copy vector values in batch. Currently, we have copyFrom and copyFromSafe APIs. However, they are not enough, as copying values individually is not performant.

Reporter: Liya Fan / @liyafan82
Assignee: Liya Fan / @liyafan82

Related issues:

• [Java] Support for combining multiple vectors under VectorSchemaRoot (blocks)
• [Java] Support concating validity bits efficiently (is blocked by)

PRs and other links:

• GitHub Pull Request #5916

_{Note: This issue was originally created as ARROW-7073. Please see the migration documentation for further details.}

[asfimport]

Micah Kornfield / @emkornfield:
Issue resolved by pull request 5916
#5916