[improve][broker] Remove ClassLoaderSwitcher to avoid objects allocations and consistent the codestyle

[dao-jun]

Motivation

Apply #22790 's pattern and address the comment #22767 (comment)

Modifications

Verifying this change

• Make sure that the change passes the CI checks.

(Please pick either of the following options)

This change is a trivial rework / code cleanup without any test coverage.

(or)

This change is already covered by existing tests, such as (please describe tests).

(or)

This change added tests and can be verified as follows:

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• Added integration tests for end-to-end deployment with large payloads (10MB)
• Extended integration test for recovery after broker failure

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

If the box was checked, please highlight the changes

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository:

[eolivelli]

+1

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.22%. Comparing base (bbc6224) to head (69b0ab7).
Report is 313 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #22796      +/-   ##
============================================
- Coverage     73.57%   73.22%   -0.35%     
  Complexity    32624    32624              
============================================
  Files          1877     1890      +13     
  Lines        139502   141628    +2126     
  Branches      15299    15540     +241     
============================================
+ Hits         102638   103708    +1070     
- Misses        28908    29928    +1020     
- Partials       7956     7992      +36     

Flag	Coverage Δ
inttests	27.39% <0.00%> (+2.80%)	⬆️
systests	24.63% <0.00%> (+0.30%)	⬆️
unittests	72.24% <100.00%> (-0.61%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...ugin/servlet/AdditionalServletWithClassLoader.java	88.88% <100.00%> (+4.67%)	⬆️
...roker/protocol/ProtocolHandlerWithClassLoader.java	92.50% <100.00%> (+4.03%)	⬆️

... and 365 files with indirect coverage changes

[mattisonchao]

Object allocations are not a big deal here. The main purpose is that you wanna align the code style, right?

[dao-jun]

Object allocations are not a big deal here. The main purpose is that you wanna align the code style, right?

Yes, Protocol handler and AdditionalServlet is not in the message publish/consume calling chain, and they don't call frequently, the PR just consistent the codestyle.

[dao-jun]

merging..