Use 'application' if spring.application.name is not set.

Also log a warning.

fixes gh-152

spring-cloud-zookeeper-config/src/main/java/org/springframework/cloud/zookeeper/config/ZookeeperPropertySourceLocator.java

@@ -81,6 +81,11 @@ public class ZookeeperPropertySourceLocator implements PropertySourceLocator {
 		if (environment instanceof ConfigurableEnvironment) {
 			ConfigurableEnvironment env = (ConfigurableEnvironment) environment;
 			String appName = env.getProperty("spring.application.name");
+			if (appName == null) {
+				// use default "application" (which config client does)
+				appName = "application";
+				log.warn("spring.application.name is not set. Using default of 'application'");
+			}
 			List<String> profiles = Arrays.asList(env.getActiveProfiles());
 
 			String root = this.properties.getRoot();

spring-cloud-zookeeper-config/src/test/java/org/springframework/cloud/zookeeper/config/ZookeeperPropertySourceLocatorNoApplicationNameTests.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2013-2015 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.zookeeper.config;
+
+import org.apache.curator.framework.CuratorFramework;
+import org.apache.curator.framework.api.GetChildrenBuilder;
+import org.junit.Test;
+import org.mockito.Mockito;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.mock.env.MockEnvironment;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+/**
+ * @author Spencer Gibb
+ */
+public class ZookeeperPropertySourceLocatorNoApplicationNameTests {
+
+	@Test
+	public void defaultSpringApplicationNameWorks() {
+		CuratorFramework curator = mock(CuratorFramework.class);
+		when(curator.getChildren()).thenReturn(mock(GetChildrenBuilder.class));
+		ZookeeperPropertySourceLocator locator = new ZookeeperPropertySourceLocator(curator, new ZookeeperConfigProperties());
+		locator.locate(new MockEnvironment());
+	}
+}