static CircuitBreakerRule of(CircuitBreakerRule... circuitBreakerRules) {
        requireNonNull(circuitBreakerRules, "circuitBreakerRules");
        checkArgument(circuitBreakerRules.length > 0, "circuitBreakerRules can't be empty.");
        if (circuitBreakerRules.length == 1) {
            return circuitBreakerRules[0];
        }
        return of(ImmutableList.copyOf(circuitBreakerRules));
    }
Returns a {@link CircuitBreakerRule} that combines the specified {@link CircuitBreakerRule}s.
core/src/main/java/com/linecorp/armeria/client/circuitbreaker/CircuitBreakerRule.java