gistfile1.txt

@Test
public void fluxErrorHandling_withRetryBackoff(){

    Flux<String> stringFlux = Flux.just("a","b","c")
            .concatWith(Flux.error(new RuntimeException("Exception Occurred")))
            .concatWith(Flux.just("D"))
            .onErrorMap((e) -> new CustomException(e))
            .retryBackoff(2, Duration.ofSeconds(5));// when you want to perform a backoff before retry

    StepVerifier.create(stringFlux.log())
            .expectSubscription()
            .expectNext("a","b","c")
            .expectNext("a","b","c")
            .expectNext("a","b","c")
            .expectError(IllegalStateException.class)
            .verify();
}