doOnError and onErrorContinue test

package com.test;

import lombok.extern.slf4j.Slf4j;
import reactor.core.publisher.Flux;

@Slf4j
public class FluxFindWithSubscribe {
  // 1. Both have doOnError and onErrorContinue, only onErrorContinue will work no matter outside or inside of them
  // 2. Both have onErrorContinue inside and outside, onErrorContinue inside will work, onErrorContinue outside will not
  // 3. Both have doOnError inside and outside, both work, inside will log first
  // 4. if it is a API, will also output exception in log if do not has onErrorContinue just has doOnError
  public static void main(String[] args){
    FluxFind fluxFind = new FluxFind();
    Flux.from(fluxFind.find())
        .doOnError(e -> log.error("Has Error outside"))
        //.onErrorContinue((e, o) -> log.error("Error occurred outside"))
        .subscribe(i -> log.info("{}", i), e -> log.error("{}", e));
  }
}

package com.test;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import reactor.core.publisher.Flux;

@Component
@Slf4j
public class FluxFind {
  public Flux<Integer> find(){
    return  Flux.from(doFind(1))
        .concatWith(doFind(2))
        //.doOnError(e -> log.error("Has Error inside"));
        .onErrorContinue((e, o) -> log.error("Error occurred inside"));
  }

  private Flux<Integer> doFind(int i){
    return  Flux.just(i).map(s ->{
      if(s ==1){
        throw new RuntimeException();
      }else{
        return s;
      }});
  }
}

18:15:06.147 [main] ERROR com.test.FluxFind - Error occurred inside
18:15:06.147 [main] INFO com.test.FluxFindWithSubscribe - 2

package com.test;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import reactor.core.publisher.Flux;

@Component
@Slf4j
public class FluxFind {
  // For 3 layers of flux, inner layer and outside layer with onErrorContinue but no exception,
  // middle layer with exception.
  // Finally, outside catch the exception and onErrorContinue will work, result:
  // 18:34:03.217 [main] ERROR com.test.FluxFind - Error occurred outside
  // 18:34:03.218 [main] INFO com.test.FluxFind - 2
  public static void main(String[] args) {
    FluxFind fluxFind = new FluxFind();
    Flux.from(fluxFind.find())
        .doOnError(e -> log.error("Has Error outside"))
        .onErrorContinue((e, o) -> log.error("Error occurred outside"))
        .subscribe(i -> log.info("{}", i), e -> log.error("{}", e));
  }
  
  public Flux<Integer> find(){
    return  Flux.from(doFind(1))
        .concatWith(doFind(2));
        //.doOnError(e -> log.error("Has Error inside"));
        //.onErrorContinue((e, o) -> log.error("Error occurred inside"));
  }

  private Flux<Integer> doFind(int i){
    return  getMapFlux(i).map(s ->{
      if(s ==1){
        throw new RuntimeException();
      }else{
        return s;
      }});
  }

  private Flux<Integer> getMapFlux(int s){
    return  Flux.just(s)
        .map(i -> i)
        .onErrorContinue((e, o) -> log.error("Error occurred inside"));
  }
}

package com.test;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

@Slf4j
public class FluxFindString {
  // onErrorContinue will not work when Mono.error
  // 18:54:30.305 [main] ERROR com.test.FluxFindString - Has Error outside
  // 18:54:30.308 [main] ERROR com.test.FluxFindString - {}
  // java.lang.RuntimeException: null
  //    at com.test.FluxFindString.doFind(FluxFindString.java:27)
  //    at com.test.FluxFindString.find(FluxFindString.java:21)
  //    at com.test.FluxFindString.main(FluxFindString.java:14)
  public static void main(String[] args) {
    FluxFindString fluxFind = new FluxFindString();
    Flux.from(fluxFind.find())
        .doOnError(e -> log.error("Has Error outside"))
        .onErrorContinue((e, o) -> log.error("Error occurred outside"))
        .subscribe(i -> log.info("{}", i), e -> log.error("{}", e));
  }

  public Flux<String> find() {
    return Flux.from(doFind(null))
        .concatWith(doFind("2"))
        .onErrorContinue((e, o) -> log.error("Error occurred inside"));
  }

  private Mono<String> doFind(String i) {
    return Mono.justOrEmpty(i).switchIfEmpty(Mono.error(new RuntimeException()));
  }
}

public class OnErrorContinue2 {
  public static void main(String[] args) {
    // -5
    // 数据：0,发生错误：java.lang.ArithmeticException: / by zero
    // -10
    // 10
    // 5
    // Exception in thread "main" java.lang.ArithmeticException: / by zero
    //    at com.test.reactor.OnErrorContinue2.main(OnErrorContinue2.java:16)
    Flux.just(-2, -1, 0, 1, 2)
        .map(n -> 10 / n)
        .onErrorContinue((e, n) -> System.err.println("数据：" + n + ",发生错误：" + e))
        .subscribe(System.out::println, System.err::println);
    // Exception in thread "main" java.lang.ArithmeticException: / by zero
    //    at com.test.reactor.OnErrorContinue2.main(OnErrorContinue2.java:9)
    /*Flux.just(10 / -2, 10 / -1, 10 / 0, 10 / 1, 10 / 2)
        .onErrorContinue((e, n) -> System.err.println("数据：" + n + ",发生错误：" + e))
        .subscribe(System.out::println, System.err::println);*/

  }
}

/**
 * {@link Flux#onErrorContinue} works for {@link Throwable}, not works for {@link Mono#error} which create a
 * {@link Mono} that terminates with the specified error immediately after being subscribed to.
 */