Medium Error Handling

Resume with Fallback Stream

Create a Flux that emits "A", "B" then throws an error. Use onErrorResume() to switch to a fallback Flux emitting "X", "Y", "Z". Subscribe and print all values.

Expected: A, B, X, Y, Z (each on a new line).

Expected

A
B
X
Y
Z

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Main.kt

Resume with Fallback Stream

medium⏱ 15 minkotlinreactorchallengeerror-handling

Starter

Create a Flux that emits "A", "B" then throws an error. Use onErrorResume() to switch to a fallback Flux emitting "X", "Y", "Z". Subscribe and print all values.

Expected: A, B, X, Y, Z (each on a new line).

Why this works

onErrorResume() catches an error and replaces the failed stream with a new Publisher. Unlike onErrorReturn() which provides a single value, onErrorResume() can provide an entire new stream.

Expected output

A
B
X
Y
Z

Resume with Fallback Stream

Create a Flux that emits "A", "B" then throws an error. Use onErrorResume() to switch to a fallback Flux emitting "X", "Y", "Z". Subscribe and print all values.

Expected: A, B, X, Y, Z (each on a new line).

Expected

A B X Y Z

Resume with Fallback Stream

medium⏱ 15 minkotlinreactorchallengeerror-handling

Starter

Create a Flux that emits "A", "B" then throws an error. Use onErrorResume() to switch to a fallback Flux emitting "X", "Y", "Z". Subscribe and print all values.

Expected: A, B, X, Y, Z (each on a new line).

Why this works

onErrorResume() catches an error and replaces the failed stream with a new Publisher. Unlike onErrorReturn() which provides a single value, onErrorResume() can provide an entire new stream.

Expected output

A B X Y Z