Spring / Spring Webflux Interview questions

What does Mono.defer() do?

Mono. defer(monoSupplier) lets you provide the whole expression that supplies the resulting Mono instance. The evaluation of this expression is deferred until somebody subscribes. Inside of this expression you can additionally use control structures like Mono.

When you run Mono.just() it creates immediately an Observable(Mono)and reuses it but when you use defer it doesn't create it immediately it creates a new Observable in every subscribe.

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Spring / Spring Webflux Interview questions

What does Mono.defer() do?

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