Replay with Cache

Create a Flux emitting "A", "B", "C" and use .cache() to replay all elements to late subscribers. Subscribe twice and verify both get all values.

cache() replays previously emitted elements to new subscribers.

Expected

Sub1: A
Sub1: B
Sub1: C
Sub2: A
Sub2: B
Sub2: C

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Main.kt

Replay with Cache

medium⏱ 15 minkotlinreactorchallengehot-cold

Create a Flux emitting "A", "B", "C" and use .cache() to replay all elements to late subscribers. Subscribe twice and verify both get all values.

cache() replays previously emitted elements to new subscribers.

Why this works

cache() turns a Flux into a hot publisher that replays all cached elements to new subscribers. Unlike share(), which may cause late subscribers to miss items, cache() ensures everyone gets the full history.

Expected output

Sub1: A
Sub1: B
Sub1: C
Sub2: A
Sub2: B
Sub2: C

Replay with Cache

Create a Flux emitting "A", "B", "C" and use .cache() to replay all elements to late subscribers. Subscribe twice and verify both get all values.

cache() replays previously emitted elements to new subscribers.

Expected

Sub1: A Sub1: B Sub1: C Sub2: A Sub2: B Sub2: C

Replay with Cache

medium⏱ 15 minkotlinreactorchallengehot-cold

Create a Flux emitting "A", "B", "C" and use .cache() to replay all elements to late subscribers. Subscribe twice and verify both get all values.

cache() replays previously emitted elements to new subscribers.

Why this works

Expected output

Sub1: A Sub1: B Sub1: C Sub2: A Sub2: B Sub2: C