Fix NPE when instance has no status page url.

fixes gh-1285

spring-cloud-netflix-eureka-server/src/main/java/org/springframework/cloud/netflix/eureka/server/EurekaController.java

@@ -233,8 +233,10 @@ public class EurekaController {
 					LinkedHashMap<String, Object> instance = new LinkedHashMap<>();
 					instances.add(instance);
 					instance.put("id", p.first());
-					instance.put("url", p.second());
-					instance.put("isHref", p.second().startsWith("http"));
+					String url = p.second();
+					instance.put("url", url);
+					boolean isHref = url != null && url.startsWith("http");
+					instance.put("isHref", isHref);
 					/*
 					 * String id = p.first(); String url = p.second(); if(url != null &&
 					 * url.startsWith("http")){

spring-cloud-netflix-eureka-server/src/test/java/org/springframework/cloud/netflix/eureka/server/EurekaControllerTest.java

@@ -0,0 +1,126 @@
+/*
+ * Copyright 2013-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.springframework.cloud.netflix.eureka.server;
+
+import java.lang.reflect.Field;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.mock.web.MockHttpServletRequest;
+import org.springframework.util.ReflectionUtils;
+
+import com.netflix.appinfo.ApplicationInfoManager;
+import com.netflix.appinfo.DataCenterInfo;
+import com.netflix.appinfo.InstanceInfo;
+import com.netflix.appinfo.MyDataCenterInfo;
+import com.netflix.discovery.shared.Application;
+import com.netflix.eureka.EurekaServerContext;
+import com.netflix.eureka.EurekaServerContextHolder;
+import com.netflix.eureka.cluster.PeerEurekaNode;
+import com.netflix.eureka.cluster.PeerEurekaNodes;
+import com.netflix.eureka.registry.PeerAwareInstanceRegistry;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.nullValue;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class EurekaControllerTest {
+
+	private ApplicationInfoManager infoManager;
+
+	@Before
+	public void setup() throws Exception {
+		PeerEurekaNodes peerEurekaNodes = mock(PeerEurekaNodes.class);
+		when(peerEurekaNodes.getPeerNodesView()).thenReturn(Collections.<PeerEurekaNode>emptyList());
+
+		InstanceInfo instanceInfo = InstanceInfo.Builder.newBuilder()
+				.setAppName("test")
+				.setDataCenterInfo(new MyDataCenterInfo(DataCenterInfo.Name.MyOwn))
+				.build();
+
+		this.infoManager = mock(ApplicationInfoManager.class);
+		setInstance(this.infoManager);
+		when(this.infoManager.getInfo()).thenReturn(instanceInfo);
+
+		Application myapp = new Application("myapp");
+		myapp.addInstance(InstanceInfo.Builder.newBuilder()
+				.setAppName("myapp")
+				.setDataCenterInfo(new MyDataCenterInfo(DataCenterInfo.Name.MyOwn))
+				.setInstanceId("myapp:1")
+				.build());
+
+		ArrayList<Application> applications = new ArrayList<>();
+		applications.add(myapp);
+
+		PeerAwareInstanceRegistry registry = mock(PeerAwareInstanceRegistry.class);
+		when(registry.getSortedApplications()).thenReturn(applications);
+
+		EurekaServerContext serverContext = mock(EurekaServerContext.class);
+		EurekaServerContextHolder.initialize(serverContext);
+		when(serverContext.getRegistry()).thenReturn(registry);
+		when(serverContext.getPeerEurekaNodes()).thenReturn(peerEurekaNodes);
+		when(serverContext.getApplicationInfoManager()).thenReturn(this.infoManager);
+
+	}
+
+	@After
+	public void teardown() throws Exception {
+		setInstance(null);
+	}
+
+	void setInstance(ApplicationInfoManager infoManager) throws IllegalAccessException {
+		Field instance = ReflectionUtils.findField(ApplicationInfoManager.class, "instance");
+		ReflectionUtils.makeAccessible(instance);
+		instance.set(null, infoManager);
+	}
+
+	@Test
+	public void testStatus() throws Exception {
+		Map<String, Object> model = new HashMap<>();
+
+		EurekaController controller = new EurekaController(infoManager);
+
+		controller.status(new MockHttpServletRequest("GET", "/"), model);
+
+		Map<String, Object> app = getFirst(model, "apps");
+		Map<String, Object> instanceInfo = getFirst(app, "instanceInfos");
+		Map<String, Object> instance = getFirst(instanceInfo, "instances");
+
+		assertThat("id was wrong", (String)instance.get("id"), is(equalTo("myapp:1")));
+		assertThat("url was not null", instance.get("url"), is(nullValue()));
+		assertThat("isHref was wrong", (Boolean)instance.get("isHref"), is(false));
+	}
+
+	@SuppressWarnings("unchecked")
+	Map<String, Object> getFirst(Map<String, Object> model, String key) {
+		List<Map<String, Object>> apps = (List<Map<String, Object>>) model.get(key);
+		assertThat(key +" was wrong size", apps, is(hasSize(1)));
+		return apps.get(0);
+	}
+
+}