ProjectReactor_Mono_Flux

Learn

• https://projectreactor.io/learn
• https://projectreactor.io/docs/core/release/api/reactor/core/scheduler/Schedulers.html

Flux

• map

• flatMap
  • parallel execution
• concatMap
  • sequential execution

Add Behavior

• doOnNext
  • dc
• doOnComplete
  • Flux completes successfully
• doOnTerminate
  • Flux terminates either successfully or failing with an error
• doOnError
  • Flux completes with an error

Mono

• map

• flatMap

Add Behavior

• doOnNext
  • Mono completes by emitting value
• doOnSuccess
  • Mono completes with either T or null
• doOnError
  • Mono completes with error

Error handling

• onErrorResume(Throwable -> Publisher)
  • used to convert to another Mono/Flux
• onErrorReturn(Object fallbackValue)
  • suppress exception and return default value
• onErrorContinue
  • https://stackoverflow.com/questions/69510106/does-reactor-onerrorcontinue-operator-let-the-original-sequence-continue
  • should avoid using this operator
• onErrorMap
• onErrorStop
• onErrorComplete

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Fire and Forget

• https://github.com/reactor/reactor-core/issues/3358

Hot and Cold Publishers

• Hot Publishers ⇒ evaluated eagerly
• Cold Publishers ⇒ evaluated lazily
• https://www.baeldung.com/java-mono-defer

Reactor context vs ThreadLocal variables