Add Multi-threaded Batch Document

[HAKSOAT]

This addresses #1778

[HAKSOAT]

Hi, @lintool I have a PR in progress. I need your thoughts on some things:

1. The original document methods L663 and L680 take in an integer and a string respectively. However, I'm not very sure how I can go about doing this without creating two batchDocument methods with different names. Hence, I'd like to know what the best practice is for Anserini. The PR only currently tackles batch for internal lucene docs and I'd like to add something for collection docid too.

2. After compiling I saw a bunch of modified markdown files. Will I push all of them as well? I didn't push because I didn't want them to mess up the PR review.

[codecov-commenter]

Codecov Report

Merging #1857 (54e5baa) into master (1842eef) will increase coverage by 0.01%.
The diff coverage is 66.66%.

@@             Coverage Diff              @@
##             master    #1857      +/-   ##
============================================
+ Coverage     57.70%   57.71%   +0.01%     
- Complexity     1055     1058       +3     
============================================
  Files           179      179              
  Lines         10232    10250      +18     
  Branches       1407     1409       +2     
============================================
+ Hits           5904     5916      +12     
- Misses         3836     3841       +5     
- Partials        492      493       +1     

Impacted Files	Coverage Δ
...c/main/java/io/anserini/search/SimpleSearcher.java	64.15% <66.66%> (+0.17%)	⬆️

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[lintool]

hi @HAKSOAT - thanks for this PR.

Let's go with a single method for now, called batchGetDocument. It should take a list of (external) collection ids, which is the more common case.

If you update and merge in current master, it should get rid of the new markdown edits?

Thanks!

[lintool]

lg, but can you please build a fatjar, copy over to pyserini, and make sure it connects up on the pyserini end? i.e., let's build the bindings on the pyserini end just to confirm everything works e2e.

[HAKSOAT]

lg, but can you please build a fatjar, copy over to pyserini, and make sure it connects up on the pyserini end? i.e., let's build the bindings on the pyserini end just to confirm everything works e2e.

Noted.

[HAKSOAT]

lg, but can you please build a fatjar, copy over to pyserini, and make sure it connects up on the pyserini end? i.e., let's build the bindings on the pyserini end just to confirm everything works e2e.

It works. I'll put a PR through for this on Pyserini.