Move discovery client flux creation code to a method.

spring-cloud-loadbalancer/src/main/java/org/springframework/cloud/loadbalancer/core/DiscoveryClientServiceInstanceListSupplier.java

@@ -50,36 +50,24 @@ public class DiscoveryClientServiceInstanceListSupplier implements ServiceInstan
 
 	private static final Log LOG = LogFactory.getLog(DiscoveryClientServiceInstanceListSupplier.class);
 
-	private Duration timeout = Duration.ofSeconds(30);
-
 	private final String serviceId;
 
-	private final Flux<List<ServiceInstance>> serviceInstances;
+	private final Object delegate;
+
+	private Duration timeout = Duration.ofSeconds(30);
+
+	private Flux<List<ServiceInstance>> serviceInstances = null;
 
 	public DiscoveryClientServiceInstanceListSupplier(DiscoveryClient delegate, Environment environment) {
 		this.serviceId = environment.getProperty(PROPERTY_NAME);
 		resolveTimeout(environment);
-		this.serviceInstances = Flux.defer(() -> Flux.just(delegate.getInstances(serviceId)))
-				.subscribeOn(Schedulers.boundedElastic()).timeout(timeout, Flux.defer(() -> {
-					logTimeout();
-					return Flux.just(new ArrayList<>());
-				})).onErrorResume(error -> {
-					logException(error);
-					return Flux.just(new ArrayList<>());
-				});
+		this.delegate = delegate;
 	}
 
 	public DiscoveryClientServiceInstanceListSupplier(ReactiveDiscoveryClient delegate, Environment environment) {
 		this.serviceId = environment.getProperty(PROPERTY_NAME);
 		resolveTimeout(environment);
-		this.serviceInstances = Flux
-				.defer(() -> delegate.getInstances(serviceId).collectList().flux().timeout(timeout, Flux.defer(() -> {
-					logTimeout();
-					return Flux.just(new ArrayList<>());
-				})).onErrorResume(error -> {
-					logException(error);
-					return Flux.just(new ArrayList<>());
-				}));
+		this.delegate = delegate;
 	}
 
 	@Override
@@ -89,9 +77,42 @@ public class DiscoveryClientServiceInstanceListSupplier implements ServiceInstan
 
 	@Override
 	public Flux<List<ServiceInstance>> get() {
+		if (serviceInstances == null) {
+			if (delegate instanceof DiscoveryClient) {
+				serviceInstances = fluxFromBlockingDelegate((DiscoveryClient) delegate);
+			}
+			else if (delegate instanceof ReactiveDiscoveryClient) {
+				serviceInstances = fluxFromReactiveDelegate((ReactiveDiscoveryClient) delegate);
+			}
+			else {
+				serviceInstances = Flux.empty();
+			}
+		}
 		return serviceInstances;
 	}
 
+	private Flux<List<ServiceInstance>> fluxFromReactiveDelegate(ReactiveDiscoveryClient delegate) {
+		return Flux
+				.defer(() -> (delegate).getInstances(serviceId).collectList().flux().timeout(timeout, Flux.defer(() -> {
+					logTimeout();
+					return Flux.just(new ArrayList<>());
+				})).onErrorResume(error -> {
+					logException(error);
+					return Flux.just(new ArrayList<>());
+				}));
+	}
+
+	private Flux<List<ServiceInstance>> fluxFromBlockingDelegate(DiscoveryClient delegate) {
+		return Flux.defer(() -> Flux.just((delegate).getInstances(serviceId))).subscribeOn(Schedulers.boundedElastic())
+				.timeout(timeout, Flux.defer(() -> {
+					logTimeout();
+					return Flux.just(new ArrayList<>());
+				})).onErrorResume(error -> {
+					logException(error);
+					return Flux.just(new ArrayList<>());
+				});
+	}
+
 	private void resolveTimeout(Environment environment) {
 		String providedTimeout = environment.getProperty(SERVICE_DISCOVERY_TIMEOUT);
 		if (providedTimeout != null) {