Merge pull request spring-projects#110 from cfritz0127/cleaner-shutdown-on-deregistration-error

* cleaner-shutdown-on-deregistration-error:
  Catch and log exceptions that occur when attempting to deregister a service during shutdown.

Author: spencergibb

spring-cloud-commons/src/main/java/org/springframework/cloud/client/discovery/AbstractDiscoveryLifecycle.java

@@ -16,8 +16,13 @@
 
 package org.springframework.cloud.client.discovery;
 
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+
 import javax.annotation.PreDestroy;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.springframework.beans.BeansException;
 import org.springframework.boot.context.embedded.EmbeddedServletContainerInitializedEvent;
 import org.springframework.cloud.client.discovery.event.InstanceRegisteredEvent;
@@ -26,16 +31,15 @@
 import org.springframework.context.ApplicationListener;
 import org.springframework.core.env.Environment;
 
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicInteger;
-
 /**
  * Lifecycle methods that may be useful and common to various DiscoveryClient implementations.
  * @author Spencer Gibb
  */
 public abstract class AbstractDiscoveryLifecycle implements DiscoveryLifecycle,
 		ApplicationContextAware, ApplicationListener<EmbeddedServletContainerInitializedEvent> {
 
+	private static final Log logger = LogFactory.getLog(AbstractDiscoveryLifecycle.class);
+
 	private boolean autoStartup = true;
 
 	private AtomicBoolean running = new AtomicBoolean(false);
@@ -74,7 +78,11 @@ public boolean isAutoStartup() {
 
 	@Override
 	public void stop(Runnable callback) {
-		stop();
+		try {
+			stop();
+		} catch (Exception e) {
+			logger.error("A problem occurred attempting to stop discovery lifecycle", e);
+		}
 		callback.run();
 	}