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Spring / Resilience4j Interview questions

How do you apply @CircuitBreaker in a Spring Boot service?

Annotate the method that makes the risky call with @CircuitBreaker(name = "paymentService", fallbackMethod = "paymentFallback"), and Spring AOP wraps it in a proxy that routes the call through the named CircuitBreaker instance.

@CircuitBreaker(name = "paymentService", fallbackMethod = "paymentFallback")
public PaymentResponse charge(PaymentRequest req) {
    return paymentClient.charge(req);
}

private PaymentResponse paymentFallback(PaymentRequest req, Throwable t) {
    return PaymentResponse.declined("service unavailable");
}

The name attribute must match an instance configured under resilience4j.circuitbreaker.instances.paymentService in application.yml (or fall back to shared defaults); the fallback method must live in the same class and match the original method's return type plus an added Throwable parameter.

The "name" attribute in @CircuitBreaker(name="paymentService", ...) must:
A fallback method referenced by fallbackMethod must:

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