Use RouteLocator interface.

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/ZuulConfiguration.java

@@ -76,7 +76,7 @@ public class ZuulConfiguration {
 	}
 
 	@Bean
-	@ConditionalOnMissingBean
+	@ConditionalOnMissingBean(RouteLocator.class)
 	public RouteLocator routeLocator() {
 		return new SimpleRouteLocator(this.server.getServletPrefix(),
 				this.zuulProperties);

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/ZuulProxyConfiguration.java

@@ -135,7 +135,7 @@ public class ZuulProxyConfiguration extends ZuulConfiguration {
 	protected static class RoutesEndpointConfiguration {
 
 		@Bean
-		public RoutesEndpoint zuulEndpoint(DiscoveryClientRouteLocator routeLocator) {
+		public RoutesEndpoint zuulEndpoint(RouteLocator routeLocator) {
 			return new RoutesEndpoint(routeLocator);
 		}
 

spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/zuul/SampleZuulProxyApplicationTests.java

@@ -24,15 +24,20 @@ import javax.servlet.http.HttpServletRequest;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.test.IntegrationTest;
 import org.springframework.boot.test.SpringApplicationConfiguration;
 import org.springframework.boot.test.TestRestTemplate;
+import org.springframework.cloud.client.discovery.DiscoveryClient;
 import org.springframework.cloud.netflix.ribbon.RibbonClient;
 import org.springframework.cloud.netflix.ribbon.RibbonClients;
 import org.springframework.cloud.netflix.ribbon.SpringClientFactory;
 import org.springframework.cloud.netflix.ribbon.StaticServerList;
+import org.springframework.cloud.netflix.zuul.filters.RouteLocator;
+import org.springframework.cloud.netflix.zuul.filters.ZuulProperties;
+import org.springframework.cloud.netflix.zuul.filters.discovery.DiscoveryClientRouteLocator;
 import org.springframework.cloud.netflix.zuul.filters.route.RestClientRibbonCommand;
 import org.springframework.cloud.netflix.zuul.filters.route.RestClientRibbonCommandFactory;
 import org.springframework.cloud.netflix.zuul.filters.route.RibbonCommandContext;
@@ -82,6 +87,9 @@ import lombok.SneakyThrows;
 @DirtiesContext
 public class SampleZuulProxyApplicationTests extends ZuulProxyTestBase {
 
+	@Autowired
+	RouteLocator routeLocator;
+
 	@Test
 	public void simpleHostRouteWithTrailingSlash() {
 		this.routes.addRoute("/self/**", "http://localhost:" + this.port + "/");
@@ -191,6 +199,12 @@ public class SampleZuulProxyApplicationTests extends ZuulProxyTestBase {
 				this.ribbonCommandFactory instanceof SampleZuulProxyApplication.MyRibbonCommandFactory);
 	}
 
+	@Test
+	public void routeLocatorOverridden() {
+		assertTrue("routeLocator not a MyRouteLocator",
+				this.routeLocator instanceof SampleZuulProxyApplication.MyRouteLocator);
+	}
+
 }
 
 // Don't use @SpringBootApplication because we don't want to component scan
@@ -238,6 +252,11 @@ class SampleZuulProxyApplication extends ZuulProxyTestBase.AbstractZuulProxyAppl
 		return new MyRibbonCommandFactory(clientFactory);
 	}
 
+	@Bean
+	public RouteLocator routeLocator(DiscoveryClient discoveryClient, ZuulProperties zuulProperties) {
+		return new MyRouteLocator("/", discoveryClient, zuulProperties);
+	}
+
 	public static void main(String[] args) {
 		SpringApplication.run(SampleZuulProxyApplication.class, args);
 	}
@@ -299,4 +318,11 @@ class SampleZuulProxyApplication extends ZuulProxyTestBase.AbstractZuulProxyAppl
 		}
 
 	}
+
+	static class MyRouteLocator extends DiscoveryClientRouteLocator {
+
+		public MyRouteLocator(String servletPath, DiscoveryClient discovery, ZuulProperties properties) {
+			super(servletPath, discovery, properties);
+		}
+	}
 }