4.x: +shared, +parallel, +blocking Scheduler

[akarnokd]

Originally present in my extensions repo. Prime time to include them in RxJava proper:

Also did the rx4. -> rxjava4.

https://github.com/akarnokd/RxJavaExtensions/tree/3.x/src/main/java/hu/akarnokd/rxjava3/schedulers

Resolves: #8082
Resolves: #8081

[github-actions]

🐷 TruffleHog + Entropy Beauty Scan

Average entropy of changed code: 4.535 bits/char
Verdict: ✅ Mid-4 beauty detected (thoughtful human code!)

Changed files entropy:

src/main/java/io/reactivex/rxjava4/core/Scheduler.java: 4.535

✅ No secrets or suspicious high-entropy strings found.

Mid-4 beauty heuristic in action — powered by our entropy chats! 😊

[codecov]

Codecov Report

❌ Patch coverage is 91.34615% with 36 lines in your changes missing coverage. Please review.
✅ Project coverage is 98.74%. Comparing base (8af1ab4) to head (a9156c4).
⚠️ Report is 1 commits behind head on 4.x.

Files with missing lines	Patch %	Lines
...nal/schedulers/BlockingCurrentThreadScheduler.java	87.26%	6 Missing and 14 partials ⚠️
...rxjava4/internal/schedulers/ParallelScheduler.java	94.44%	1 Missing and 8 partials ⚠️
...va/io/reactivex/rxjava4/schedulers/Schedulers.java	50.00%	2 Missing and 1 partial ⚠️
...x/rxjava4/internal/schedulers/SharedScheduler.java	96.55%	0 Missing and 2 partials ⚠️
...eactivex/rxjava4/schedulers/BlockingScheduler.java	75.00%	2 Missing ⚠️

❌ Your patch status has failed because the patch coverage (91.34%) is below the target coverage (95.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff              @@
##                4.x    #8154      +/-   ##
============================================
- Coverage     98.76%   98.74%   -0.02%     
- Complexity     6872     6938      +66     
============================================
  Files           768      773       +5     
  Lines         48578    48990     +412     
  Branches       6512     6586      +74     
============================================
+ Hits          47978    48376     +398     
+ Misses          455      454       -1     
- Partials        145      160      +15     

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[github-actions]

🐷 TruffleHog + Entropy Beauty Scan

Average entropy of changed code: 4.535 bits/char
Verdict: ✅ Mid-4 beauty detected (thoughtful human code!)

Changed files entropy:

src/main/java/io/reactivex/rxjava4/core/Scheduler.java: 4.535

✅ No secrets or suspicious high-entropy strings found.

Mid-4 beauty heuristic in action — powered by our entropy chats! 😊

[github-actions]

🐷 TruffleHog + Entropy Beauty Scan

Average entropy of changed code: 4.535 bits/char
Verdict: ✅ Mid-4 beauty detected (thoughtful human code!)

Changed files entropy:

src/main/java/io/reactivex/rxjava4/core/Scheduler.java: 4.535

✅ No secrets or suspicious high-entropy strings found.

Mid-4 beauty heuristic in action — powered by our entropy chats! 😊

[github-actions]

🐷 TruffleHog + Entropy Beauty Scan

Average entropy of changed code: 4.535 bits/char
Verdict: ✅ Mid-4 beauty detected (thoughtful human code!)

Changed files entropy:

src/main/java/io/reactivex/rxjava4/core/Scheduler.java: 4.535

✅ No secrets or suspicious high-entropy strings found.

Mid-4 beauty heuristic in action — powered by our entropy chats! 😊

[github-actions]

🐷 TruffleHog + Entropy Beauty Scan

Average entropy of changed code: 4.535 bits/char
Verdict: ✅ Mid-4 beauty detected (thoughtful human code!)

Changed files entropy:

src/main/java/io/reactivex/rxjava4/core/Scheduler.java: 4.535

✅ No secrets or suspicious high-entropy strings found.

Mid-4 beauty heuristic in action — powered by our entropy chats! 😊