Sonar fixes to pooling

Made various changes to the pooling feature to address some of the
sonar issues.
Remove duplicate classes, Pair & Triple.
Fix sonar issue about duplicate process(xxx) methods.
Remove extra items from pom.xml and add assembly builder.
Fix license text in pom.xml, inadvertently reformatted.
Fix a few typos in comments and change LinkedList to Queue.
Move assembly.xml to correct source directory.
Replace ScheduledFuture<?> with CancellableScheduledTask, to satisfy
sonar.
Eliminate "TODO" items: add logging, delay after sending Offline
message.
Add more logging in process(Message) methods.
Begin creating end-to-end junit test, fixed bugs found as a result.
Restore logback-test.xml to WARN.
Fix merge conflict - restored test properties file.

Change-Id: Ic70a8cee49678ea0fc3da309699aec1f6088fe70
Issue-ID: POLICY-728
Signed-off-by: Jim Hahn <jrh3@att.com>

22 files changed, 702 insertions, 692 deletions

diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/CancellableScheduledTask.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/CancellableScheduledTask.java
new file mode 100644
index 00000000..b16f44ad
--- /dev/null
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/CancellableScheduledTask.java
@@ -0,0 +1,33 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.drools.pooling;
+
+/**
+ * A scheduled task that can be cancelled.
+ */
+@FunctionalInterface
+public interface CancellableScheduledTask {
+
+    /**
+     * Cancels the scheduled task.
+     */
+    public void cancel();
+}
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/DmaapManager.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/DmaapManager.java
index 98543f29..102eda75 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/DmaapManager.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/DmaapManager.java
@@ -58,14 +58,14 @@ public class DmaapManager {
     private final TopicSink topicSink;
 
     /**
-     * Topic sources. In theory, there's only one item in this list, the
-     * internal DMaaP topic.
+     * Topic sources. In theory, there's only one item in this list, the internal DMaaP
+     * topic.
      */
     private final List<TopicSource> sources;
 
     /**
-     * Topic sinks. In theory, there's only one item in this list, the internal
-     * DMaaP topic.
+     * Topic sinks. In theory, there's only one item in this list, the internal DMaaP
+     * topic.
      */
     private final List<TopicSink> sinks;
 
@@ -112,8 +112,8 @@ public class DmaapManager {
     }
 
     /**
-     * Used by junit tests to set the factory used to create various objects
-     * used by this class.
+     * Used by junit tests to set the factory used to create various objects used by this
+     * class.
      * 
      * @param factory the new factory
      */
@@ -129,8 +129,7 @@ public class DmaapManager {
      * Finds the topic source associated with the internal DMaaP topic.
      * 
      * @return the topic source
-     * @throws PoolingFeatureException if the source doesn't exist or is not
-     *         filterable
+     * @throws PoolingFeatureException if the source doesn't exist or is not filterable
      */
     private FilterableTopicSource findTopicSource() throws PoolingFeatureException {
         for (TopicSource src : sources) {
@@ -174,6 +173,7 @@ public class DmaapManager {
         }
 
         try {
+            logger.info("start publishing to topic {}", topic);
             topicSink.start();
             publishing = true;
 
@@ -184,13 +184,28 @@ public class DmaapManager {
 
     /**
      * Stops the publisher.
+     * 
+     * @param waitMs time, in milliseconds, to wait for the sink to transmit any queued
+     *        messages and close
      */
-    public void stopPublisher() {
+    public void stopPublisher(long waitMs) {
         if (!publishing) {
             return;
         }
 
+        /*
+         * Give the sink a chance to transmit messages in the queue. It would be better if
+         * "waitMs" could be passed to sink.stop(), but that isn't an option at this time.
+         */
+        try {
+            Thread.sleep(waitMs);
+
+        } catch (InterruptedException e) {
+            logger.warn("message transmission stopped due to {}", e.getMessage());
+        }
+
         try {
+            logger.info("stop publishing to topic {}", topic);
             publishing = false;
             topicSink.stop();
 
@@ -209,6 +224,7 @@ public class DmaapManager {
             return;
         }
 
+        logger.info("start consuming from topic {}", topic);
         topicSource.register(listener);
         consuming = true;
     }
@@ -223,6 +239,7 @@ public class DmaapManager {
             return;
         }
 
+        logger.info("stop consuming from topic {}", topic);
         consuming = false;
         topicSource.unregister(listener);
     }
@@ -230,16 +247,16 @@ public class DmaapManager {
     /**
      * Sets the server-side filter to be used by the consumer.
      * 
-     * @param filter the filter string, or {@code null} if no filter is to be
-     *        used
+     * @param filter the filter string, or {@code null} if no filter is to be used
      * @throws PoolingFeatureException if the topic is not filterable
      */
     public void setFilter(String filter) throws PoolingFeatureException {
         try {
+            logger.debug("change filter for topic {} to {}", topic, filter);
             topicSource.setFilter(filter);
 
         } catch (UnsupportedOperationException e) {
-            throw new PoolingFeatureException("cannot filter topic " + topic);
+            throw new PoolingFeatureException("cannot filter topic " + topic, e);
         }
     }
 
@@ -247,8 +264,7 @@ public class DmaapManager {
      * Publishes a message to the sink.
      * 
      * @param msg message to be published
-     * @throws PoolingFeatureException if an error occurs or the publisher isn't
-     *         running
+     * @throws PoolingFeatureException if an error occurs or the publisher isn't running
      */
     public void publish(String msg) throws PoolingFeatureException {
         if (!publishing) {
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/FeatureEnabledChecker.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/FeatureEnabledChecker.java
deleted file mode 100644
index d2f32043..00000000
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/FeatureEnabledChecker.java
+++ /dev/null
@@ -1,144 +0,0 @@
-/*
- * ============LICENSE_START=======================================================
- * ONAP
- * ================================================================================
- * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
- * ================================================================================
- * 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.
- * ============LICENSE_END=========================================================
- */
-
-package org.onap.policy.drools.pooling;
-
-// TODO move to policy-utils
-
-import java.lang.annotation.Annotation;
-import java.lang.reflect.Field;
-import java.util.Properties;
-import org.onap.policy.common.utils.properties.SpecPropertyConfiguration;
-import org.onap.policy.common.utils.properties.exception.PropertyException;
-
-/**
- * Checks whether or not a feature is enabled. The name of the "enable" property
- * is assumed to be of the form accepted by a {@link SpecPropertyConfiguration},
- * which contains a substitution place-holder into which a "specializer" (e.g.,
- * controller or session name) is substituted.
- */
-public class FeatureEnabledChecker {
-
-    /**
-     * 
-     */
-    private FeatureEnabledChecker() {
-        super();
-    }
-
-    /**
-     * Determines if a feature is enabled for a particular specializer.
-     * 
-     * @param props properties from which to extract the "enabled" flag
-     * @param specializer specializer to be substituted into the property name
-     *        when extracting
-     * @param propName the name of the "enabled" property
-     * @return {@code true} if the feature is enabled, or {@code false} if it is
-     *         not enabled (or if the property doesn't exist)
-     * @throws IllegalArgumentException if the "enabled" property is not a
-     *         boolean value
-     */
-    public static boolean isFeatureEnabled(Properties props, String specializer, String propName) {
-
-        try {
-            return new Config(specializer, props, propName).isEnabled();
-
-        } catch (PropertyException e) {
-            throw new IllegalArgumentException("cannot check property " + propName, e);
-        }
-    }
-
-
-    /**
-     * Configuration used to extract the value.
-     */
-    private static class Config extends SpecPropertyConfiguration {
-
-        /**
-         * There is a bit of trickery here. This annotation is just a
-         * place-holder to get the superclass to invoke the
-         * {@link #setValue(java.lang.reflect.Field, Properties, Property)
-         * setValue()} method. When that's invoked, we'll substitute
-         * {@link #propOverride} instead of this annotation.
-         */
-        @Property(name = "feature-enabled-property-place-holder")
-        private boolean enabled;
-
-        /**
-         * Annotation that will actually be used to set the field.
-         */
-        private Property propOverride;
-
-        /**
-         * 
-         * @param specializer specializer to be substituted into the property
-         *        name when extracting
-         * @param props properties from which to extract the "enabled" flag
-         * @param propName the name of the "enabled" property
-         * @throws PropertyException if an error occurs
-         */
-        public Config(String specializer, Properties props, String propName) throws PropertyException {
-            super(specializer);
-
-            propOverride = new Property() {
-
-                @Override
-                public String name() {
-                    return propName;
-                }
-
-                @Override
-                public String defaultValue() {
-                    // feature is disabled by default
-                    return "false";
-                }
-
-                @Override
-                public String accept() {
-                    return "";
-                }
-
-                @Override
-                public Class<? extends Annotation> annotationType() {
-                    return Property.class;
-                }
-            };
-
-            setAllFields(props);
-        }
-
-        /**
-         * Substitutes {@link #propOverride} for "prop".
-         */
-        @Override
-        protected boolean setValue(Field field, Properties props, Property prop) throws PropertyException {
-            return super.setValue(field, props, propOverride);
-        }
-
-        /**
-         * 
-         * @return {@code true} if the feature is enabled, {@code false}
-         *         otherwise
-         */
-        public boolean isEnabled() {
-            return enabled;
-        }
-    };
-}
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeature.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeature.java
index da47a031..21cbc4db 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeature.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeature.java
@@ -20,44 +20,41 @@
 
 package org.onap.policy.drools.pooling;
 
-import java.io.IOException;
 import java.util.Properties;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Function;
 import org.onap.policy.common.utils.properties.exception.PropertyException;
 import org.onap.policy.drools.controller.DroolsController;
-import org.onap.policy.drools.core.PolicySessionFeatureAPI;
 import org.onap.policy.drools.event.comm.Topic.CommInfrastructure;
 import org.onap.policy.drools.features.DroolsControllerFeatureAPI;
 import org.onap.policy.drools.features.PolicyControllerFeatureAPI;
+import org.onap.policy.drools.features.PolicyEngineFeatureAPI;
+import org.onap.policy.drools.persistence.SystemPersistence;
 import org.onap.policy.drools.system.PolicyController;
-import org.onap.policy.drools.utils.PropertyUtil;
+import org.onap.policy.drools.system.PolicyEngine;
+import org.onap.policy.drools.util.FeatureEnabledChecker;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Controller/session pooling. Multiple hosts may be launched, all servicing the
- * same controllers/sessions. When this feature is enabled, the requests are
- * divided across the different hosts, instead of all running on a single,
- * active host.
+ * Controller/session pooling. Multiple hosts may be launched, all servicing the same
+ * controllers/sessions. When this feature is enabled, the requests are divided across the
+ * different hosts, instead of all running on a single, active host.
  * <p>
- * With each controller, there is an associated DMaaP topic that is used for
- * internal communication between the different hosts serving the controller.
+ * With each controller, there is an associated DMaaP topic that is used for internal
+ * communication between the different hosts serving the controller.
  */
-public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControllerFeatureAPI, PolicySessionFeatureAPI {
+public class PoolingFeature implements PolicyEngineFeatureAPI, PolicyControllerFeatureAPI, DroolsControllerFeatureAPI {
 
     private static final Logger logger = LoggerFactory.getLogger(PoolingFeature.class);
 
-    // TODO state-management doesn't allow more than one active host at a time
-
     /**
      * Factory used to create objects.
      */
     private static Factory factory;
 
     /**
-     * Entire set of feature properties, including those specific to various
-     * controllers.
+     * Entire set of feature properties, including those specific to various controllers.
      */
     private Properties featProps = null;
 
@@ -67,9 +64,9 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
     private ConcurrentHashMap<String, PoolingManagerImpl> ctlr2pool = new ConcurrentHashMap<>(107);
 
     /**
-     * Arguments passed to beforeOffer(), which are saved for when the
-     * beforeInsert() is called later. As multiple threads can be active within
-     * the methods at the same time, we must keep this in thread local storage.
+     * Arguments passed to beforeOffer(), which are saved for when the beforeInsert() is
+     * called later. As multiple threads can be active within the methods at the same
+     * time, we must keep this in thread local storage.
      */
     private ThreadLocal<OfferArgs> offerArgs = new ThreadLocal<>();
 
@@ -98,20 +95,11 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
         return 0;
     }
 
-    /**
-     * @throws PoolingFeatureRtException if the properties cannot be read or are
-     *         invalid
-     */
     @Override
-    public void globalInit(String[] args, String configDir) {
-        logger.info("initializing pooling feature");
-
-        try {
-            featProps = PropertyUtil.getProperties(configDir + "/feature-pooling-dmaap.properties");
-
-        } catch (IOException ex) {
-            throw new PoolingFeatureRtException(ex);
-        }
+    public boolean beforeStart(PolicyEngine engine) {
+        logger.info("initializing " + PoolingProperties.FEATURE_NAME);
+        featProps = factory.getProperties(PoolingProperties.FEATURE_NAME);
+        return false;
     }
 
     /**
@@ -205,8 +193,8 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
     @Override
     public boolean beforeOffer(PolicyController controller, CommInfrastructure protocol, String topic2, String event) {
         /*
-         * As this is invoked a lot, we'll directly call the manager's method
-         * instead of using the functional interface via doManager().
+         * As this is invoked a lot, we'll directly call the manager's method instead of
+         * using the functional interface via doManager().
          */
         PoolingManagerImpl mgr = ctlr2pool.get(controller.getName());
         if (mgr == null) {
@@ -226,6 +214,7 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
 
         OfferArgs args = offerArgs.get();
         if (args == null) {
+            logger.warn("missing arguments for feature-pooling-dmaap in beforeInsert");
             return false;
         }
 
@@ -234,16 +223,21 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
             controller = factory.getController(droolsController);
 
         } catch (IllegalArgumentException | IllegalStateException e) {
+            logger.warn("cannot get controller for {} {}", droolsController.getGroupId(),
+                            droolsController.getArtifactId(), e);
             return false;
         }
 
+
         if (controller == null) {
+            logger.warn("cannot determine controller for {} {}", droolsController.getGroupId(),
+                            droolsController.getArtifactId());
             return false;
         }
 
         /*
-         * As this is invoked a lot, we'll directly call the manager's method
-         * instead of using the functional interface via doManager().
+         * As this is invoked a lot, we'll directly call the manager's method instead of
+         * using the functional interface via doManager().
          */
         PoolingManagerImpl mgr = ctlr2pool.get(controller.getName());
         if (mgr == null) {
@@ -264,14 +258,12 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
     }
 
     /**
-     * Executes a function using the manager associated with the controller.
-     * Catches any exceptions from the function and re-throws it as a runtime
-     * exception.
+     * Executes a function using the manager associated with the controller. Catches any
+     * exceptions from the function and re-throws it as a runtime exception.
      * 
      * @param controller
      * @param func function to be executed
-     * @return {@code true} if the function handled the request, {@code false}
-     *         otherwise
+     * @return {@code true} if the function handled the request, {@code false} otherwise
      * @throws PoolingFeatureRtException if an error occurs
      */
     private boolean doManager(PolicyController controller, MgrFunc func) {
@@ -284,26 +276,28 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
             return func.apply(mgr);
 
         } catch (PoolingFeatureException e) {
-            throw e.toRuntimeException();
+            throw new PoolingFeatureRtException(e);
         }
     }
 
     /**
-     * Executes a function using the manager associated with the controller and
-     * then deletes the manager. Catches any exceptions from the function and
-     * re-throws it as a runtime exception.
+     * Executes a function using the manager associated with the controller and then
+     * deletes the manager. Catches any exceptions from the function and re-throws it as a
+     * runtime exception.
      * 
      * @param controller
      * @param func function to be executed
-     * @return {@code true} if the function handled the request, {@code false}
-     *         otherwise
+     * @return {@code true} if the function handled the request, {@code false} otherwise
      * @throws PoolingFeatureRtException if an error occurs
      */
     private boolean doDeleteManager(PolicyController controller, Function<PoolingManagerImpl, Boolean> func) {
 
+        String name = controller.getName();
+        logger.info("remove feature-pool-dmaap manager for {}", name);
+
         // NOTE: using "remove()" instead of "get()"
 
-        PoolingManagerImpl mgr = ctlr2pool.remove(controller.getName());
+        PoolingManagerImpl mgr = ctlr2pool.remove(name);
 
         if (mgr == null) {
             return false;
@@ -321,8 +315,8 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
         /**
          * 
          * @param mgr
-         * @return {@code true} if the request was handled by the manager,
-         *         {@code false} otherwise
+         * @return {@code true} if the request was handled by the manager, {@code false}
+         *         otherwise
          * @throws PoolingFeatureException
          */
         public boolean apply(PoolingManagerImpl mgr) throws PoolingFeatureException;
@@ -367,6 +361,14 @@ public class PoolingFeature implements PolicyControllerFeatureAPI, DroolsControl
     public static class Factory {
 
         /**
+         * @param featName feature name
+         * @return the properties for the specified feature
+         */
+        public Properties getProperties(String featName) {
+            return SystemPersistence.manager.getProperties(featName);
+        }
+
+        /**
          * Makes a pooling manager for a controller.
          * 
          * @param controller
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeatureException.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeatureException.java
index 5efd1414..c3c81879 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeatureException.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingFeatureException.java
@@ -47,13 +47,4 @@ public class PoolingFeatureException extends Exception {
         super(message, cause, enableSuppression, writableStackTrace);
     }
 
-    /**
-     * Converts the exception to a runtime exception.
-     * 
-     * @return a new runtime exception, wrapping this exception
-     */
-    public PoolingFeatureRtException toRuntimeException() {
-        return new PoolingFeatureRtException(this);
-    }
-
 }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManager.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManager.java
index de08d1e1..5036b605 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManager.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManager.java
@@ -21,7 +21,6 @@
 package org.onap.policy.drools.pooling;
 
 import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ScheduledFuture;
 import org.onap.policy.drools.pooling.message.BucketAssignments;
 import org.onap.policy.drools.pooling.message.Forward;
 import org.onap.policy.drools.pooling.message.Message;
@@ -48,19 +47,19 @@ public interface PoolingManager {
     public String getHost();
 
     /**
-     * Gets the name of the internal DMaaP topic used by this manager to
-     * communicate with its other hosts.
+     * Gets the name of the internal DMaaP topic used by this manager to communicate with
+     * its other hosts.
      * 
      * @return the name of the internal DMaaP topic
      */
     public String getTopic();
 
     /**
-     * Indicates that communication with internal DMaaP topic failed, typically
-     * due to a missed heart beat. Stops the PolicyController.
+     * Indicates that communication with internal DMaaP topic failed, typically due to a
+     * missed heart beat. Stops the PolicyController.
      * 
-     * @return a latch that can be used to determine when the controller's
-     *         stop() method has completed
+     * @return a latch that can be used to determine when the controller's stop() method
+     *         has completed
      */
     public CountDownLatch internalTopicFailed();
 
@@ -68,14 +67,16 @@ public interface PoolingManager {
      * Starts distributing requests according to the given bucket assignments.
      * 
      * @param assignments must <i>not</i> be {@code null}
+     * @return a latch that can be used to determine when the events in the event queue
+     *         have all be processed
      */
-    public void startDistributing(BucketAssignments assignments);
+    public CountDownLatch startDistributing(BucketAssignments assignments);
 
     /**
      * Gets the current bucket assignments.
      * 
-     * @return the current bucket assignments, or {@code null} if no assignments
-     *         have been made
+     * @return the current bucket assignments, or {@code null} if no assignments have been
+     *         made
      */
     public BucketAssignments getAssignments();
 
@@ -95,8 +96,7 @@ public interface PoolingManager {
     public void publish(String channel, Message msg);
 
     /**
-     * Handles a {@link Forward} event that was received from the internal
-     * topic.
+     * Handles a {@link Forward} event that was received from the internal topic.
      * 
      * @param event
      */
@@ -107,9 +107,9 @@ public interface PoolingManager {
      * 
      * @param delayMs delay, in milliseconds
      * @param task
-     * @return a future that can be used to cancel the timer
+     * @return a new scheduled task
      */
-    public ScheduledFuture<?> schedule(long delayMs, StateTimerTask task);
+    public CancellableScheduledTask schedule(long delayMs, StateTimerTask task);
 
     /**
      * Schedules a timer to fire repeatedly.
@@ -117,9 +117,9 @@ public interface PoolingManager {
      * @param initialDelayMs initial delay, in milliseconds
      * @param delayMs delay, in milliseconds
      * @param task
-     * @return a future that can be used to cancel the timer
+     * @return a new scheduled task
      */
-    public ScheduledFuture<?> scheduleWithFixedDelay(long initialDelayMs, long delayMs, StateTimerTask task);
+    public CancellableScheduledTask scheduleWithFixedDelay(long initialDelayMs, long delayMs, StateTimerTask task);
 
     /**
      * Transitions to the "start" state.
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManagerImpl.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManagerImpl.java
index cd71670d..422efdd7 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManagerImpl.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingManagerImpl.java
@@ -30,6 +30,7 @@ import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
 import org.onap.policy.drools.controller.DroolsController;
 import org.onap.policy.drools.event.comm.Topic.CommInfrastructure;
 import org.onap.policy.drools.event.comm.TopicListener;
@@ -38,6 +39,7 @@ import org.onap.policy.drools.pooling.message.BucketAssignments;
 import org.onap.policy.drools.pooling.message.Forward;
 import org.onap.policy.drools.pooling.message.Leader;
 import org.onap.policy.drools.pooling.message.Message;
+import org.onap.policy.drools.pooling.message.Offline;
 import org.onap.policy.drools.pooling.state.ActiveState;
 import org.onap.policy.drools.pooling.state.IdleState;
 import org.onap.policy.drools.pooling.state.InactiveState;
@@ -52,39 +54,30 @@ import org.slf4j.LoggerFactory;
 import com.fasterxml.jackson.core.JsonProcessingException;
 
 /**
- * Implementation of a {@link PoolingManager}. Until bucket assignments have
- * been made, events coming from external topics are saved in a queue for later
- * processing. Once assignments are made, the saved events are processed. In
- * addition, while the controller is locked, events are still forwarded to other
- * hosts and bucket assignments are still updated, based on any {@link Leader}
- * messages that it receives.
+ * Implementation of a {@link PoolingManager}. Until bucket assignments have been made,
+ * events coming from external topics are saved in a queue for later processing. Once
+ * assignments are made, the saved events are processed. In addition, while the controller
+ * is locked, events are still forwarded to other hosts and bucket assignments are still
+ * updated, based on any {@link Leader} messages that it receives.
  */
 public class PoolingManagerImpl implements PoolingManager, TopicListener {
 
     private static final Logger logger = LoggerFactory.getLogger(PoolingManagerImpl.class);
 
-    // TODO metrics, audit logging
-
     /**
      * Maximum number of times a message can be forwarded.
      */
     public static final int MAX_HOPS = 5;
 
     /**
-     * Type of item that the extractors will be extracting.
-     */
-    private static final String EXTRACTOR_TYPE = "requestId";
-
-    /**
-     * Prefix for extractor properties.
+     * Factory used to create various objects. Can be overridden during junit testing.
      */
-    private static final String PROP_EXTRACTOR_PREFIX = "extractor." + EXTRACTOR_TYPE;
+    private static Factory factory = new Factory();
 
     /**
-     * Factory used to create various objects. Can be overridden during junit
-     * testing.
+     * ID of the last host that was created.
      */
-    private static Factory factory = new Factory();
+    private static final AtomicReference<String> lastHost = new AtomicReference<>(null);
 
     /**
      * ID of this host.
@@ -102,14 +95,12 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     private final PolicyController controller;
 
     /**
-     * Where to offer events that have been forwarded to this host (i.e, the
-     * controller).
+     * Where to offer events that have been forwarded to this host (i.e, the controller).
      */
     private final TopicListener listener;
 
     /**
-     * Used to encode & decode request objects received from & sent to a rule
-     * engine.
+     * Used to encode & decode request objects received from & sent to a rule engine.
      */
     private final Serializer serializer;
 
@@ -129,19 +120,18 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     private final ClassExtractors extractors;
 
     /**
-     * Lock used while updating {@link #current}. In general, public methods
-     * must use this, while private methods assume the lock is already held.
+     * Lock used while updating {@link #current}. In general, public methods must use
+     * this, while private methods assume the lock is already held.
      */
     private final Object curLocker = new Object();
 
     /**
      * Current state.
      * <p>
-     * This uses a finite state machine, wherein the state object contains all
-     * of the data relevant to that state. Each state object has a process()
-     * method, specific to each type of {@link Message} subclass. The method
-     * returns the next state object, or {@code null} if the state is to remain
-     * the same.
+     * This uses a finite state machine, wherein the state object contains all of the data
+     * relevant to that state. Each state object has a process() method, specific to each
+     * type of {@link Message} subclass. The method returns the next state object, or
+     * {@code null} if the state is to remain the same.
      */
     private State current;
 
@@ -177,13 +167,16 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
         this.controller = controller;
         this.props = props;
 
+        lastHost.set(this.host);
+
         try {
             this.listener = (TopicListener) controller;
             this.serializer = new Serializer();
             this.topic = props.getPoolingTopic();
             this.eventq = factory.makeEventQueue(props);
 
-            SpecProperties spec = new SpecProperties(PROP_EXTRACTOR_PREFIX, controller.getName());
+            SpecProperties spec = new SpecProperties(PoolingProperties.PROP_EXTRACTOR_PREFIX, controller.getName(),
+                            props.getSource());
             this.extractors = factory.makeClassExtractors(spec);
 
             this.dmaapMgr = factory.makeDmaapManager(props);
@@ -197,7 +190,7 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
 
         } catch (PoolingFeatureException e) {
             logger.error("failed to attach internal DMaaP topic to controller {}", controller.getName());
-            throw e.toRuntimeException();
+            throw new PoolingFeatureRtException(e);
         }
     }
 
@@ -210,6 +203,16 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
+     * Used by junit tests.
+     * 
+     * @return the ID of the last host that was created, or {@code null} if no hosts have
+     *         been created yet
+     */
+    protected static String getLastHost() {
+        return lastHost.get();
+    }
+
+    /**
      * Should only be used by junit tests.
      * 
      * @return the current state
@@ -234,22 +237,22 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
-     * Indicates that the controller is about to start. Starts the publisher for
-     * the internal topic, and creates a thread pool for the timers.
+     * Indicates that the controller is about to start. Starts the publisher for the
+     * internal topic, and creates a thread pool for the timers.
      * 
-     * @throws PoolingFeatureException if the internal topic publisher cannot be
-     *         started
+     * @throws PoolingFeatureException if the internal topic publisher cannot be started
      */
     public void beforeStart() throws PoolingFeatureException {
         synchronized (curLocker) {
             if (scheduler == null) {
                 dmaapMgr.startPublisher();
 
+                logger.debug("make scheduler thread for topic {}", getTopic());
                 scheduler = factory.makeScheduler();
 
                 /*
-                 * Only a handful of timers at any moment, thus we can afford to
-                 * take the time to remove them when they're cancelled.
+                 * Only a handful of timers at any moment, thus we can afford to take the
+                 * time to remove them when they're cancelled.
                  */
                 scheduler.setRemoveOnCancelPolicy(true);
                 scheduler.setMaximumPoolSize(1);
@@ -260,9 +263,9 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
-     * Indicates that the controller has successfully started. Starts the
-     * consumer for the internal topic, enters the {@link StartState}, and sets
-     * the filter for the initial state.
+     * Indicates that the controller has successfully started. Starts the consumer for the
+     * internal topic, enters the {@link StartState}, and sets the filter for the initial
+     * state.
      */
     public void afterStart() {
         synchronized (curLocker) {
@@ -274,8 +277,8 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
-     * Indicates that the controller is about to stop. Stops the consumer, the
-     * scheduler, and the current state.
+     * Indicates that the controller is about to stop. Stops the consumer, the scheduler,
+     * and the current state.
      */
     public void beforeStop() {
         ScheduledThreadPoolExecutor sched;
@@ -287,23 +290,19 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
             if (!(current instanceof IdleState)) {
                 dmaapMgr.stopConsumer(this);
                 changeState(new IdleState(this));
-
-                // TODO
-                /*
-                 * Need a brief delay here to allow "offline" message to be
-                 * transmitted?
-                 */
+                publishAdmin(new Offline(getHost()));
             }
         }
 
         if (sched != null) {
+            logger.debug("stop scheduler for topic {}", getTopic());
             sched.shutdownNow();
         }
     }
 
     /**
-     * Indicates that the controller has stopped. Stops the publisher and logs a
-     * warning if any events are still in the queue.
+     * Indicates that the controller has stopped. Stops the publisher and logs a warning
+     * if any events are still in the queue.
      */
     public void afterStop() {
         synchronized (curLocker) {
@@ -312,25 +311,33 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
                 eventq.clear();
             }
 
-            dmaapMgr.stopPublisher();
+            /*
+             * stop the publisher, but allow time for any Offline message to be
+             * transmitted
+             */
+            dmaapMgr.stopPublisher(props.getOfflinePubWaitMs());
         }
     }
 
     /**
-     * Indicates that the controller is about to be locked. Enters the idle
-     * state, as all it will be doing is forwarding messages.
+     * Indicates that the controller is about to be locked. Enters the idle state, as all
+     * it will be doing is forwarding messages.
      */
     public void beforeLock() {
+        logger.info("locking manager for topic {}", getTopic());
+
         synchronized (curLocker) {
             changeState(new IdleState(this));
         }
     }
 
     /**
-     * Indicates that the controller has been unlocked. Enters the start state,
-     * if the controller is running.
+     * Indicates that the controller has been unlocked. Enters the start state, if the
+     * controller is running.
      */
     public void afterUnlock() {
+        logger.info("unlocking manager for topic {}", getTopic());
+
         synchronized (curLocker) {
             if (controller.isAlive() && current instanceof IdleState && scheduler != null) {
                 changeState(new StartState(this));
@@ -339,8 +346,8 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
-     * Changes the finite state machine to a new state, provided the new state
-     * is not {@code null}.
+     * Changes the finite state machine to a new state, provided the new state is not
+     * {@code null}.
      * 
      * @param newState new state, or {@code null} if to remain unchanged
      */
@@ -379,30 +386,46 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
         CountDownLatch latch = new CountDownLatch(1);
 
         /*
-         * We don't want to build up items in our queue if we can't forward them
-         * to other hosts, so we just stop the controller.
+         * We don't want to build up items in our queue if we can't forward them to other
+         * hosts, so we just stop the controller.
          * 
          * Use a background thread to prevent deadlocks.
          */
-        new Thread() {
-            @Override
-            public void run() {
-                controller.stop();
-                latch.countDown();
-            }
-        }.start();
+        new Thread(() -> {
+            controller.stop();
+            latch.countDown();
+        }).start();
 
         return latch;
     }
 
     @Override
-    public ScheduledFuture<?> schedule(long delayMs, StateTimerTask task) {
-        return scheduler.schedule(new TimerAction(task), delayMs, TimeUnit.MILLISECONDS);
+    public CancellableScheduledTask schedule(long delayMs, StateTimerTask task) {
+        // wrap the task in a TimerAction and schedule it
+        ScheduledFuture<?> fut = scheduler.schedule(new TimerAction(task), delayMs, TimeUnit.MILLISECONDS);
+
+        // wrap the future in a "CancellableScheduledTask"
+        return new CancellableScheduledTask() {
+            @Override
+            public void cancel() {
+                fut.cancel(false);
+            }
+        };
     }
 
     @Override
-    public ScheduledFuture<?> scheduleWithFixedDelay(long initialDelayMs, long delayMs, StateTimerTask task) {
-        return scheduler.scheduleWithFixedDelay(new TimerAction(task), initialDelayMs, delayMs, TimeUnit.MILLISECONDS);
+    public CancellableScheduledTask scheduleWithFixedDelay(long initialDelayMs, long delayMs, StateTimerTask task) {
+        // wrap the task in a TimerAction and schedule it
+        ScheduledFuture<?> fut = scheduler.scheduleWithFixedDelay(new TimerAction(task), initialDelayMs, delayMs,
+                        TimeUnit.MILLISECONDS);
+
+        // wrap the future in a "CancellableScheduledTask"
+        return new CancellableScheduledTask() {
+            @Override
+            public void cancel() {
+                fut.cancel(false);
+            }
+        };
     }
 
     @Override
@@ -412,6 +435,8 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
 
     @Override
     public void publish(String channel, Message msg) {
+        logger.info("publish {} to {} on topic {}", msg.getClass().getSimpleName(), channel, getTopic());
+
         msg.setChannel(channel);
 
         try {
@@ -434,8 +459,8 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
      * 
      * @param topic2
      * @param event
-     * @return {@code true} if the event was handled, {@code false} if the
-     *         controller should handle it
+     * @return {@code true} if the event was handled, {@code false} if the controller
+     *         should handle it
      */
     @Override
     public void onTopicEvent(CommInfrastructure commType, String topic2, String event) {
@@ -452,20 +477,19 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
-     * Called by the PolicyController before it offers the event to the
-     * DroolsController. If the controller is locked, then it isn't processing
-     * events. However, they still need to be forwarded, thus in that case, they
-     * are decoded and forwarded.
+     * Called by the PolicyController before it offers the event to the DroolsController.
+     * If the controller is locked, then it isn't processing events. However, they still
+     * need to be forwarded, thus in that case, they are decoded and forwarded.
      * <p>
-     * On the other hand, if the controller is not locked, then we just return
-     * immediately and let {@link #beforeInsert(Object, String, String, Object)
-     * beforeInsert()} handle it instead, as it already has the decoded message.
+     * On the other hand, if the controller is not locked, then we just return immediately
+     * and let {@link #beforeInsert(Object, String, String, Object) beforeInsert()} handle
+     * it instead, as it already has the decoded message.
      * 
      * @param protocol
      * @param topic2
      * @param event
-     * @return {@code true} if the event was handled by the manager,
-     *         {@code false} if it must still be handled by the invoker
+     * @return {@code true} if the event was handled by the manager, {@code false} if it
+     *         must still be handled by the invoker
      */
     public boolean beforeOffer(CommInfrastructure protocol, String topic2, String event) {
 
@@ -478,15 +502,14 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
-     * Called by the DroolsController before it inserts the event into the rule
-     * engine.
+     * Called by the DroolsController before it inserts the event into the rule engine.
      * 
      * @param protocol
      * @param topic2
      * @param event original event text, as received from the Bus
      * @param event2 event, as an object
-     * @return {@code true} if the event was handled by the manager,
-     *         {@code false} if it must still be handled by the invoker
+     * @return {@code true} if the event was handled by the manager, {@code false} if it
+     *         must still be handled by the invoker
      */
     public boolean beforeInsert(CommInfrastructure protocol, String topic2, String event, Object event2) {
 
@@ -504,10 +527,10 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
      * @param protocol
      * @param topic2
      * @param event
-     * @param reqid request id extracted from the event, or {@code null} if it
-     *        couldn't be extracted
-     * @return {@code true} if the event was handled by the manager,
-     *         {@code false} if it must still be handled by the invoker
+     * @param reqid request id extracted from the event, or {@code null} if it couldn't be
+     *        extracted
+     * @return {@code true} if the event was handled by the manager, {@code false} if it
+     *         must still be handled by the invoker
      */
     private boolean handleExternal(CommInfrastructure protocol, String topic2, String event, String reqid) {
         if (reqid == null) {
@@ -524,6 +547,7 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
         Forward ev = makeForward(protocol, topic2, event, reqid);
         if (ev == null) {
             // invalid args - consume the message
+            logger.warn("constructed an invalid Forward message on topic {}", getTopic());
             return true;
         }
 
@@ -536,12 +560,13 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
      * Handles an event from an external topic.
      * 
      * @param event
-     * @return {@code true} if the event was handled, {@code false} if the
-     *         invoker should handle it
+     * @return {@code true} if the event was handled, {@code false} if the invoker should
+     *         handle it
      */
     private boolean handleExternal(Forward event) {
         if (assignments == null) {
             // no bucket assignments yet - add it to the queue
+            logger.info("queued event for request {}", event.getRequestId());
             eventq.add(event);
 
             // we've consumed the event
@@ -556,17 +581,17 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
      * Handles a {@link Forward} event, possibly forwarding it again.
      * 
      * @param event
-     * @return {@code true} if the event was handled, {@code false} if the
-     *         invoker should handle it
+     * @return {@code true} if the event was handled, {@code false} if the invoker should
+     *         handle it
      */
     private boolean handleEvent(Forward event) {
-        int bucket = Math.abs(event.getRequestId().hashCode()) % assignments.size();
-        String target = assignments.getAssignedHost(bucket);
+        String target = assignments.getAssignedHost(event.getRequestId().hashCode());
 
         if (target == null) {
             /*
              * This bucket has no assignment - just discard the event
              */
+            logger.warn("discarded event for unassigned bucket from topic {}", event.getTopic());
             return true;
         }
 
@@ -574,6 +599,7 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
             /*
              * Message belongs to this host - allow the controller to handle it.
              */
+            logger.info("handle local event for request {} from topic {}", event.getRequestId(), event.getTopic());
             return false;
         }
 
@@ -583,6 +609,7 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
                             topic);
 
         } else {
+            logger.warn("forward event hop-count={} from topic {}", event.getNumHops(), event.getTopic());
             event.bumpNumHops();
             publish(target, event);
         }
@@ -678,16 +705,21 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
      * @param event
      */
     private void inject(Forward event) {
-        intercept = false;
-        listener.onTopicEvent(event.getProtocol(), event.getTopic(), event.getPayload());
+        logger.info("inject event for request {} from topic {}", event.getRequestId(), event.getTopic());
 
-        intercept = true;
+        try {
+            intercept = false;
+            listener.onTopicEvent(event.getProtocol(), event.getTopic(), event.getPayload());
+
+        } finally {
+            intercept = true;
+        }
     }
 
     /**
-     * Handles an event from the internal topic. This uses reflection to
-     * identify the appropriate process() method to invoke, based on the type of
-     * Message that was decoded.
+     * Handles an event from the internal topic. This uses reflection to identify the
+     * appropriate process() method to invoke, based on the type of Message that was
+     * decoded.
      * 
      * @param event the serialized {@link Message} read from the internal topic
      */
@@ -711,29 +743,48 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
         } catch (NoSuchMethodException | SecurityException e) {
             logger.error("no processor for message {} for topic {}", clazz, topic, e);
 
-        } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
-            logger.error("failed to process message {} for topic {}", clazz, topic, e);
-
-        } catch (PoolingFeatureException e) {
+        } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException
+                        | PoolingFeatureException e) {
             logger.error("failed to process message {} for topic {}", clazz, topic, e);
         }
     }
 
     @Override
-    public void startDistributing(BucketAssignments assignments) {
-        if (assignments == null) {
-            return;
+    public CountDownLatch startDistributing(BucketAssignments asgn) {
+        if (asgn == null) {
+            return null;
         }
 
+        logger.info("new assignments for topic {}", getTopic());
+
         synchronized (curLocker) {
-            this.assignments = assignments;
+            assignments = asgn;
+        }
+
+        /*
+         * publish the events from the event queue, but do it in a background thread so
+         * that the state machine can enter its correct state BEFORE we start processing
+         * the events
+         */
+        CountDownLatch latch = new CountDownLatch(1);
+        
+        new Thread(() -> {
+            synchronized (curLocker) {
+                if (assignments == null) {
+                    return;
+                }
 
-            // now that we have assignments, we can process the queue
-            Forward ev;
-            while ((ev = eventq.poll()) != null) {
-                handle(ev);
+                // now that we have assignments, we can process the queue
+                Forward ev;
+                while ((ev = eventq.poll()) != null) {
+                    handle(ev);
+                }
+                
+                latch.countDown();
             }
-        }
+        }).start();
+        
+        return latch;
     }
 
     @Override
@@ -762,8 +813,8 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
     }
 
     /**
-     * Action to run a timer task. Only runs the task if the machine is still in
-     * the state that it was in when the timer was created.
+     * Action to run a timer task. Only runs the task if the machine is still in the state
+     * that it was in when the timer was created.
      */
     private class TimerAction implements Runnable {
 
@@ -790,7 +841,7 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
         public void run() {
             synchronized (curLocker) {
                 if (current == origState) {
-                    changeState(task.fire(null));
+                    changeState(task.fire());
                 }
             }
         }
@@ -818,7 +869,8 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
          * @return a new set of extractors
          */
         public ClassExtractors makeClassExtractors(Properties props) {
-            return new ClassExtractors(props, PROP_EXTRACTOR_PREFIX, EXTRACTOR_TYPE);
+            return new ClassExtractors(props, PoolingProperties.PROP_EXTRACTOR_PREFIX,
+                            PoolingProperties.EXTRACTOR_TYPE);
         }
 
         /**
@@ -846,8 +898,7 @@ public class PoolingManagerImpl implements PoolingManager, TopicListener {
          * 
          * @param drools drools controller
          * @param topic topic on which the event was received
-         * @return {@code true} if the event can be decoded, {@code false}
-         *         otherwise
+         * @return {@code true} if the event can be decoded, {@code false} otherwise
          */
         public boolean canDecodeEvent(DroolsController drools, String topic) {
             return EventProtocolCoder.manager.isDecodingSupported(drools.getGroupId(), drools.getArtifactId(), topic);
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingProperties.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingProperties.java
index 1cbe5cb9..4e8de0d0 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingProperties.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/PoolingProperties.java
@@ -30,6 +30,11 @@ import org.onap.policy.common.utils.properties.exception.PropertyException;
 public class PoolingProperties extends SpecPropertyConfiguration {
 
     /**
+     * The feature name, used to retrieve properties.
+     */
+    public static final String FEATURE_NAME = "feature-pooling-dmaap";
+
+    /**
      * Feature properties all begin with this prefix.
      */
     public static final String PREFIX = "pooling.";
@@ -51,6 +56,17 @@ public class PoolingProperties extends SpecPropertyConfiguration {
     public static final String IDENTIFICATION_MS = PREFIX + "{?.}identification.milliseconds";
     public static final String ACTIVE_HEARTBEAT_MS = PREFIX + "{?.}active.heartbeat.milliseconds";
     public static final String INTER_HEARTBEAT_MS = PREFIX + "{?.}inter.heartbeat.milliseconds";
+    public static final String OFFLINE_PUB_WAIT_MS = PREFIX + "{?.}offline.publish.wait.milliseconds";
+
+    /**
+     * Type of item that the extractors will be extracting.
+     */
+    public static final String EXTRACTOR_TYPE = "requestId";
+
+    /**
+     * Prefix for extractor properties.
+     */
+    public static final String PROP_EXTRACTOR_PREFIX = "extractor." + EXTRACTOR_TYPE;
 
     /**
      * Properties from which this was constructed.
@@ -113,6 +129,13 @@ public class PoolingProperties extends SpecPropertyConfiguration {
     private long interHeartbeatMs;
 
     /**
+     * Time, in milliseconds, to wait for an "Offline" message to be published
+     * to DMaaP.
+     */
+    @Property(name = OFFLINE_PUB_WAIT_MS, defaultValue = "3000")
+    private long offlinePubWaitMs;
+
+    /**
      * @param controllerName the name of the controller
      * @param props set of properties used to configure this
      * @throws PropertyException if an error occurs
@@ -159,4 +182,8 @@ public class PoolingProperties extends SpecPropertyConfiguration {
     public long getInterHeartbeatMs() {
         return interHeartbeatMs;
     }
+
+    public long getOfflinePubWaitMs() {
+        return offlinePubWaitMs;
+    }
 }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/SpecProperties.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/SpecProperties.java
index e4557404..31b4e614 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/SpecProperties.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/SpecProperties.java
@@ -23,8 +23,7 @@ package org.onap.policy.drools.pooling;
 import java.util.Properties;
 
 /**
- * Properties with an optional specialization (e.g., session name, controller
- * name).
+ * Properties with an optional specialization (e.g., session name, controller name).
  */
 public class SpecProperties extends Properties {
     private static final long serialVersionUID = 1L;
@@ -41,10 +40,8 @@ public class SpecProperties extends Properties {
 
     /**
      * 
-     * @param prefix the property name prefix that appears before any
-     *        specialization
-     * @param specialization the property name specialization (e.g., session
-     *        name)
+     * @param prefix the property name prefix that appears before any specialization
+     * @param specialization the property name specialization (e.g., session name)
      */
     public SpecProperties(String prefix, String specialization) {
         this.prefix = withTrailingDot(prefix);
@@ -53,10 +50,8 @@ public class SpecProperties extends Properties {
 
     /**
      * 
-     * @param prefix the property name prefix that appears before any
-     *        specialization
-     * @param specialization the property name specialization (e.g., session
-     *        name)
+     * @param prefix the property name prefix that appears before any specialization
+     * @param specialization the property name specialization (e.g., session name)
      * @param props the default properties
      */
     public SpecProperties(String prefix, String specialization, Properties props) {
@@ -77,13 +72,14 @@ public class SpecProperties extends Properties {
     }
 
     /**
-     * Gets the property whose value has the given key, looking first for the
-     * specialized property name, and then for the generalized property name.
+     * Gets the property whose value has the given key, looking first for the specialized
+     * property name, and then for the generalized property name.
      * 
      * @param key property name, without the specialization
-     * @return the value from the property set, or {@code null} if the property
-     *         set does not contain the value
+     * @return the value from the property set, or {@code null} if the property set does
+     *         not contain the value
      */
+    @Override
     public String getProperty(String key) {
         if (!key.startsWith(prefix)) {
             return super.getProperty(key);
@@ -106,4 +102,14 @@ public class SpecProperties extends Properties {
     protected String getSpecPrefix() {
         return specPrefix;
     }
+
+    @Override
+    public final int hashCode() {
+        throw new UnsupportedOperationException("HostBucket cannot be hashed");
+    }
+
+    @Override
+    public final boolean equals(Object obj) {
+        throw new UnsupportedOperationException("cannot compare HostBuckets");
+    }
 }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/ClassExtractors.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/ClassExtractors.java
index cb12a6ac..2752ca8c 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/ClassExtractors.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/ClassExtractors.java
@@ -152,7 +152,7 @@ public class ClassExtractors {
          * cannot extract data items from objects of this type, so just
          * allocated a null extractor.
          */
-        logger.warn("missing property " + prefix + clazz.getName());
+        logger.warn("missing property {}{}", prefix, clazz.getName());
         return new NullExtractor();
     }
 
@@ -166,24 +166,24 @@ public class ClassExtractors {
      */
     private Extractor buildExtractor(Class<?> clazz, String value) {
         if (!value.startsWith("${")) {
-            logger.warn("property value for " + prefix + clazz.getName() + " does not start with '${'");
+            logger.warn("property value for {}{} does not start with '${'", prefix, clazz.getName());
             return new NullExtractor();
         }
 
         if (!value.endsWith("}")) {
-            logger.warn("property value for " + prefix + clazz.getName() + " does not end with '}'");
+            logger.warn("property value for {}{} does not end with '}'", prefix, clazz.getName());
             return new NullExtractor();
         }
 
         // get the part in the middle
         String val = value.substring(2, value.length() - 1);
         if (val.startsWith(".")) {
-            logger.warn("property value for " + prefix + clazz.getName() + " begins with '.'");
+            logger.warn("property value for {}{} begins with '.'", prefix, clazz.getName());
             return new NullExtractor();
         }
 
         if (val.endsWith(".")) {
-            logger.warn("property value for " + prefix + clazz.getName() + " ends with '.'");
+            logger.warn("property value for {}{} ends with '.'", prefix, clazz.getName());
             return new NullExtractor();
         }
 
@@ -198,7 +198,7 @@ public class ClassExtractors {
             return (ext.extractors.length == 1 ? ext.extractors[0] : ext);
 
         } catch (ExtractorException e) {
-            logger.warn("cannot build extractor for " + clazz.getName());
+            logger.warn("cannot build extractor for {}", clazz.getName(), e);
             return new NullExtractor();
         }
     }
@@ -255,7 +255,7 @@ public class ClassExtractors {
 
         @Override
         public Object extract(Object object) {
-            logger.warn("cannot extract " + type + " from " + object.getClass());
+            logger.warn("cannot extract {} from {}", type, object.getClass());
             return null;
         }
     }
@@ -374,6 +374,7 @@ public class ClassExtractors {
 
             } catch (NoSuchMethodException expected) {
                 // no getXxx() method, maybe there's a field by this name
+                logger.debug("no method {} in {}", nm, clazz.getName());
                 return null;
 
             } catch (SecurityException e) {
@@ -407,9 +408,8 @@ public class ClassExtractors {
          * @param key item key within the map
          * @return a new extractor, or {@code null} if the class is not a Map
          *         subclass
-         * @throws ExtractorException
          */
-        private Pair<Extractor, Class<?>> getMapExtractor(Class<?> clazz, String key) throws ExtractorException {
+        private Pair<Extractor, Class<?>> getMapExtractor(Class<?> clazz, String key) {
 
             if (!Map.class.isAssignableFrom(clazz)) {
                 return null;
@@ -445,6 +445,7 @@ public class ClassExtractors {
 
             } catch (NoSuchFieldException expected) {
                 // no field by this name - try super class & interfaces
+                logger.debug("no field {} in {}", name, clazz.getName());
 
             } catch (SecurityException e) {
                 throw new ExtractorException("inaccessible field " + clazz + "." + name, e);
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/Extractor.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/Extractor.java
index 9ed32ae4..38d440cb 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/Extractor.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/Extractor.java
@@ -23,6 +23,7 @@ package org.onap.policy.drools.pooling.extractor;
 /**
  * Used to extract an object contained within another object.
  */
+@FunctionalInterface
 public interface Extractor {
 
     /**
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/MapExtractor.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/MapExtractor.java
index aff9d860..032ea47e 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/MapExtractor.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/extractor/MapExtractor.java
@@ -53,7 +53,7 @@ public class MapExtractor implements Extractor {
             return map.get(key);
 
         } else {
-            logger.warn("expecting a map, instead of " + object.getClass());
+            logger.warn("expecting a map, instead of {}", object.getClass());
             return null;
         }
     }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/BucketAssignments.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/BucketAssignments.java
index 8fd86c1e..ee871cbd 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/BucketAssignments.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/BucketAssignments.java
@@ -37,9 +37,19 @@ public class BucketAssignments {
     private static final Logger logger = LoggerFactory.getLogger(BucketAssignments.class);
 
     /**
-     * Number of buckets.
+     * The number of bits in the maximum number of buckets.
      */
-    public static final int MAX_BUCKETS = 1024;
+    private static final int MAX_BUCKET_BITS = 10;
+
+    /**
+     * Maximum number of buckets. Must be a power of two.
+     */
+    public static final int MAX_BUCKETS = 1 << MAX_BUCKET_BITS;
+
+    /**
+     * Used to ensure that a hash code is not negative.
+     */
+    private static final int MAX_BUCKETS_MASK = MAX_BUCKETS - 1;
 
     /**
      * Identifies the host serving a particular bucket.
@@ -55,8 +65,8 @@ public class BucketAssignments {
 
     /**
      * 
-     * @param hostArray maps a bucket number (i.e., array index) to a host. All
-     *        values must be non-null
+     * @param hostArray maps a bucket number (i.e., array index) to a host. All values
+     *        must be non-null
      */
     public BucketAssignments(String[] hostArray) {
         this.hostArray = hostArray;
@@ -97,8 +107,7 @@ public class BucketAssignments {
      * Determines if a host has an assignment.
      * 
      * @param host host to be checked
-     * @return {@code true} if the host has an assignment, {@code false}
-     *         otherwise
+     * @return {@code true} if the host has an assignment, {@code false} otherwise
      */
     @JsonIgnore
     public boolean hasAssignment(String host) {
@@ -139,23 +148,17 @@ public class BucketAssignments {
     /**
      * Gets the host assigned to a given bucket.
      * 
-     * @param bucket bucket number
-     * @return the assigned host, or {@code null} if the bucket has no assigned
-     *         host
+     * @param hashCode hash code of the item whose assignment is desired
+     * @return the assigned host, or {@code null} if the item has no assigned host
      */
     @JsonIgnore
-    public String getAssignedHost(int bucket) {
-        if (hostArray == null) {
+    public String getAssignedHost(int hashCode) {
+        if (hostArray == null || hostArray.length == 0) {
             logger.error("no buckets have been assigned");
             return null;
         }
 
-        if (bucket < 0 || bucket >= hostArray.length) {
-            logger.error("invalid bucket number {} maximum {}", bucket, hostArray.length);
-            return null;
-        }
-
-        return hostArray[bucket];
+        return hostArray[(hashCode & MAX_BUCKETS_MASK) % hostArray.length];
     }
 
     /**
@@ -169,8 +172,8 @@ public class BucketAssignments {
     }
 
     /**
-     * Checks the validity of the assignments, verifying that all buckets have
-     * been assigned to a host.
+     * Checks the validity of the assignments, verifying that all buckets have been
+     * assigned to a host.
      * 
      * @throws PoolingFeatureException if the assignments are invalid
      */
@@ -208,8 +211,6 @@ public class BucketAssignments {
         if (getClass() != obj.getClass())
             return false;
         BucketAssignments other = (BucketAssignments) obj;
-        if (!Arrays.equals(hostArray, other.hostArray))
-            return false;
-        return true;
+        return Arrays.equals(hostArray, other.hostArray);
     }
 }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/Forward.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/Forward.java
index b59cfbb2..6122d361 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/Forward.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/message/Forward.java
@@ -146,6 +146,7 @@ public class Forward extends Message {
 
     }
 
+    @Override
     @JsonIgnore
     public void checkValidity() throws PoolingFeatureException {
 
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ActiveState.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ActiveState.java
index 5f503a3b..b0a36cd9 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ActiveState.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ActiveState.java
@@ -24,16 +24,20 @@ import java.util.Arrays;
 import java.util.TreeSet;
 import org.onap.policy.drools.pooling.PoolingManager;
 import org.onap.policy.drools.pooling.message.Heartbeat;
+import org.onap.policy.drools.pooling.message.Leader;
 import org.onap.policy.drools.pooling.message.Offline;
-import org.onap.policy.drools.pooling.message.Query;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
- * The active state. In this state, this host has one more more bucket
- * assignments and processes any events associated with one of its buckets.
- * Other events are forwarded to appropriate target hosts.
+ * The active state. In this state, this host has one more more bucket assignments and
+ * processes any events associated with one of its buckets. Other events are forwarded to
+ * appropriate target hosts.
  */
 public class ActiveState extends ProcessingState {
 
+    private static final Logger logger = LoggerFactory.getLogger(ActiveState.class);
+
     /**
      * Set of hosts that have been assigned a bucket.
      */
@@ -50,8 +54,8 @@ public class ActiveState extends ProcessingState {
     private String predHost = "";
 
     /**
-     * {@code True} if we saw this host's heart beat since the last check,
-     * {@code false} otherwise.
+     * {@code True} if we saw this host's heart beat since the last check, {@code false}
+     * otherwise.
      */
     private boolean myHeartbeatSeen = false;
 
@@ -74,14 +78,14 @@ public class ActiveState extends ProcessingState {
     }
 
     /**
-     * Determine this host's neighbors based on the order of the host UUIDs.
-     * Updates {@link #succHost} and {@link #predHost}.
+     * Determine this host's neighbors based on the order of the host UUIDs. Updates
+     * {@link #succHost} and {@link #predHost}.
      */
     private void detmNeighbors() {
         if (assigned.size() < 2) {
+            logger.info("this host has no neighbors on topic {}", getTopic());
             /*
-             * this host is the only one with any assignments - it has no
-             * neighbors
+             * this host is the only one with any assignments - it has no neighbors
              */
             succHost = null;
             predHost = "";
@@ -91,11 +95,13 @@ public class ActiveState extends ProcessingState {
         if ((succHost = assigned.higher(getHost())) == null) {
             // wrapped around - successor is the first host in the set
             succHost = assigned.first();
+            logger.info("this host's successor is {} on topic {}", succHost, getTopic());
         }
 
         if ((predHost = assigned.lower(getHost())) == null) {
             // wrapped around - predecessor is the last host in the set
             predHost = assigned.last();
+            logger.info("this host's predecessor is {} on topic {}", predHost, getTopic());
         }
     }
 
@@ -109,13 +115,14 @@ public class ActiveState extends ProcessingState {
      * Adds the timers.
      */
     private void addTimers() {
+        logger.info("add timers");
 
         /*
          * heart beat generator
          */
         long genMs = getProperties().getActiveHeartbeatMs();
 
-        scheduleWithFixedDelay(genMs, genMs, xxx -> {
+        scheduleWithFixedDelay(genMs, genMs, () -> {
             genHeartbeat();
             return null;
         });
@@ -125,13 +132,14 @@ public class ActiveState extends ProcessingState {
          */
         long interMs = getProperties().getInterHeartbeatMs();
 
-        scheduleWithFixedDelay(interMs, interMs, xxx -> {
+        scheduleWithFixedDelay(interMs, interMs, () -> {
             if (myHeartbeatSeen) {
                 myHeartbeatSeen = false;
                 return null;
             }
 
             // missed my heart beat
+            logger.error("missed my heartbeat on topic {}", getTopic());
 
             return internalTopicFailed();
         });
@@ -141,13 +149,15 @@ public class ActiveState extends ProcessingState {
          */
         if (!predHost.isEmpty()) {
 
-            scheduleWithFixedDelay(interMs, interMs, xxx -> {
+            scheduleWithFixedDelay(interMs, interMs, () -> {
                 if (predHeartbeatSeen) {
                     predHeartbeatSeen = false;
                     return null;
                 }
 
                 // missed the predecessor's heart beat
+                logger.warn("missed predecessor's heartbeat on topic {}", getTopic());
+
                 publish(makeQuery());
 
                 return goQuery();
@@ -172,70 +182,85 @@ public class ActiveState extends ProcessingState {
         String src = msg.getSource();
 
         if (src == null) {
+            logger.warn("Heartbeat message has no source on topic {}", getTopic());
             return null;
 
         } else if (src.equals(getHost())) {
+            logger.info("saw my heartbeat on topic {}", getTopic());
             myHeartbeatSeen = true;
 
         } else if (src.equals(predHost)) {
+            logger.info("saw heartbeat from {} on topic {}", src, getTopic());
             predHeartbeatSeen = true;
-
+            
+        } else {
+            logger.info("ignored heartbeat message from {} on topic {}", src, getTopic());
         }
 
         return null;
     }
 
     @Override
+    public State process(Leader msg) {
+        if (!isValid(msg)) {
+            return null;
+        }
+
+        String src = msg.getSource();
+
+        if (getHost().compareTo(src) < 0) {
+            // our host would be a better leader - find out what's up
+            logger.warn("unexpected Leader message from {} on topic {}", src, getTopic());
+            return goQuery();
+        }
+
+        logger.info("have a new leader {} on topic {}", src, getTopic());
+
+        return goActive(msg.getAssignments());
+    }
+
+    @Override
     public State process(Offline msg) {
         String src = msg.getSource();
 
         if (src == null) {
+            logger.warn("Offline message has no source on topic {}", getTopic());
             return null;
 
         } else if (!assigned.contains(src)) {
             /*
-             * the offline host wasn't assigned any buckets, so just ignore the
-             * message
+             * the offline host wasn't assigned any buckets, so just ignore the message
              */
+            logger.info("ignore Offline message from unassigned source {} on topic {}", src, getTopic());
             return null;
 
         } else if (isLeader() || (predHost.equals(src) && predHost.equals(assigned.first()))) {
             /*
              * Case 1: We are the leader.
              * 
-             * Case 2: Our predecessor was the leader and it has gone offline -
-             * we should become the leader.
+             * Case 2: Our predecessor was the leader and it has gone offline - we should
+             * become the leader.
              * 
-             * In either case, we are now the leader and we must re-balance the
-             * buckets since one of the hosts has gone offline.
+             * In either case, we are now the leader and we must re-balance the buckets
+             * since one of the hosts has gone offline.
              */
 
+            logger.info("Offline message from source {} on topic {}", src, getTopic());
+
             assigned.remove(src);
 
             return becomeLeader(assigned);
 
         } else {
             /*
-             * Otherwise, we don't care right now - we'll wait for the leader to
-             * tell us it's been removed.
+             * Otherwise, we don't care right now - we'll wait for the leader to tell us
+             * it's been removed.
              */
+            logger.info("ignore Offline message from source {} on topic {}", src, getTopic());
             return null;
         }
     }
 
-    /**
-     * Transitions to the query state.
-     */
-    @Override
-    public State process(Query msg) {
-        State next = super.process(msg);
-        if (next != null) {
-            return next;
-        }
-
-        return goQuery();
-    }
-
     protected String getSuccHost() {
         return succHost;
     }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/IdleState.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/IdleState.java
index 27678360..4878c241 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/IdleState.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/IdleState.java
@@ -21,11 +21,6 @@
 package org.onap.policy.drools.pooling.state;
 
 import org.onap.policy.drools.pooling.PoolingManager;
-import org.onap.policy.drools.pooling.message.Heartbeat;
-import org.onap.policy.drools.pooling.message.Identification;
-import org.onap.policy.drools.pooling.message.Leader;
-import org.onap.policy.drools.pooling.message.Offline;
-import org.onap.policy.drools.pooling.message.Query;
 
 /**
  * Idle state, used when offline.
@@ -35,51 +30,4 @@ public class IdleState extends State {
     public IdleState(PoolingManager mgr) {
         super(mgr);
     }
-
-    @Override
-    public void stop() {
-        // do nothing - don't even send of "offline" message
-    }
-
-    /**
-     * Discards the message.
-     */
-    @Override
-    public State process(Heartbeat msg) {
-        return null;
-    }
-
-    /**
-     * Discards the message.
-     */
-    @Override
-    public State process(Identification msg) {
-        return null;
-    }
-
-    /**
-     * Copies the assignments, but doesn't change states.
-     */
-    @Override
-    public State process(Leader msg) {
-        super.process(msg);
-        return null;
-    }
-
-    /**
-     * Discards the message.
-     */
-    @Override
-    public State process(Offline msg) {
-        return null;
-    }
-
-    /**
-     * Discards the message.
-     */
-    @Override
-    public State process(Query msg) {
-        return null;
-    }
-
 }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/InactiveState.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/InactiveState.java
index 1c8e4dcc..6be2fb84 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/InactiveState.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/InactiveState.java
@@ -21,13 +21,19 @@
 package org.onap.policy.drools.pooling.state;
 
 import org.onap.policy.drools.pooling.PoolingManager;
+import org.onap.policy.drools.pooling.message.Leader;
+import org.onap.policy.drools.pooling.message.Query;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
- * The inactive state. In this state, we just wait a bit and then try to
- * re-activate. In the meantime, all messages are ignored.
+ * The inactive state. In this state, we just wait a bit and then try to re-activate. In
+ * the meantime, all messages are ignored.
  */
 public class InactiveState extends State {
 
+    private static final Logger logger = LoggerFactory.getLogger(InactiveState.class);
+
     /**
      * 
      * @param mgr
@@ -41,11 +47,36 @@ public class InactiveState extends State {
 
         super.start();
 
-        schedule(getProperties().getReactivateMs(), xxx -> goStart());
+        schedule(getProperties().getReactivateMs(), () -> goStart());
+    }
+
+    @Override
+    public State process(Leader msg) {
+        if(isValid(msg)) {
+            logger.info("received Leader message from {} on topic {}", msg.getSource(), getTopic());
+            startDistributing(msg.getAssignments());
+            
+            if(msg.getAssignments().hasAssignment(getHost())) {
+                logger.info("received Leader message on topic {}", getTopic());
+                return goActive();
+            }
+        }
+        
+        return null;
+    }
+
+    /**
+     * Generates an Identification message and goes to the query state.
+     */
+    @Override
+    public State process(Query msg) {
+        logger.info("received Query message on topic {}", getTopic());
+        publish(makeIdentification());
+        return goQuery();
     }
 
     /**
-     * Remains in this state.
+     * Remains in this state, without resetting any timers.
      */
     @Override
     protected State goInactive() {
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ProcessingState.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ProcessingState.java
index 2f830c66..1e9bb581 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ProcessingState.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/ProcessingState.java
@@ -30,15 +30,13 @@ import java.util.SortedSet;
 import java.util.TreeSet;
 import org.onap.policy.drools.pooling.PoolingManager;
 import org.onap.policy.drools.pooling.message.BucketAssignments;
-import org.onap.policy.drools.pooling.message.Identification;
 import org.onap.policy.drools.pooling.message.Leader;
 import org.onap.policy.drools.pooling.message.Query;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Any state in which events are being processed locally and forwarded, as
- * appropriate.
+ * Any state in which events are being processed locally and forwarded, as appropriate.
  */
 public class ProcessingState extends State {
 
@@ -52,8 +50,8 @@ public class ProcessingState extends State {
     /**
      * 
      * @param mgr
-     * @param leader current known leader, which need not be the same as the
-     *        assignment leader. Never {@code null}
+     * @param leader current known leader, which need not be the same as the assignment
+     *        leader. Never {@code null}
      * @throws IllegalArgumentException if an argument is invalid
      */
     public ProcessingState(PoolingManager mgr, String leader) {
@@ -76,21 +74,31 @@ public class ProcessingState extends State {
     }
 
     /**
-     * Generates an Identification message and returns {@code null}.
+     * Goes active with a new set of assignments.
+     * 
+     * @param asgn new assignments
+     * @return the new state, either Active or Inactive, depending on whether or not this
+     *         host has an assignment
      */
-    @Override
-    public State process(Query msg) {
-        publish(makeIdentification());
-        return goQuery();
+    protected State goActive(BucketAssignments asgn) {
+        startDistributing(asgn);
+
+        if (asgn.hasAssignment(getHost())) {
+            return goActive();
+
+        } else {
+            return goInactive();
+        }
     }
 
     /**
-     * Makes an Identification message.
-     * 
-     * @return a new message
+     * Generates an Identification message and goes to the query state.
      */
-    protected Identification makeIdentification() {
-        return new Identification(getHost(), getAssignments());
+    @Override
+    public State process(Query msg) {
+        logger.info("received Query message on topic {}", getTopic());
+        publish(makeIdentification());
+        return goQuery();
     }
 
     /**
@@ -132,18 +140,17 @@ public class ProcessingState extends State {
     }
 
     /**
-     * Becomes the leader. Publishes a Leader message and enters the
-     * {@link ActiveState}.
+     * Becomes the leader. Publishes a Leader message and enters the {@link ActiveState}.
      * 
      * @param alive hosts that are known to be alive
      * 
      * @return the new state
      */
     protected State becomeLeader(SortedSet<String> alive) {
-        String leader = getHost();
+        String newLeader = getHost();
 
-        if (!leader.equals(alive.first())) {
-            throw new IllegalArgumentException(leader + " cannot replace " + alive.first());
+        if (!newLeader.equals(alive.first())) {
+            throw new IllegalArgumentException(newLeader + " cannot replace " + alive.first());
         }
 
         Leader msg = makeLeader(alive);
@@ -155,8 +162,8 @@ public class ProcessingState extends State {
     }
 
     /**
-     * Makes a leader message. Assumes "this" host is the leader, and thus
-     * appears as the first host in the set of hosts that are still alive.
+     * Makes a leader message. Assumes "this" host is the leader, and thus appears as the
+     * first host in the set of hosts that are still alive.
      * 
      * @param alive hosts that are known to be alive
      * 
@@ -222,8 +229,8 @@ public class ProcessingState extends State {
     }
 
     /**
-     * Removes excess hosts from the set of available hosts. Assumes "this" host
-     * is the leader, and thus appears as the first host in the set.
+     * Removes excess hosts from the set of available hosts. Assumes "this" host is the
+     * leader, and thus appears as the first host in the set.
      * 
      * @param maxHosts maximum number of hosts to be retained
      * @param avail available hosts
@@ -231,9 +238,9 @@ public class ProcessingState extends State {
     private void removeExcessHosts(int maxHosts, SortedSet<String> avail) {
         while (avail.size() > maxHosts) {
             /*
-             * Don't remove this host, as it's the leader. Since the leader is
-             * always at the front of the sorted set, we'll just pick off hosts
-             * from the back of the set.
+             * Don't remove this host, as it's the leader. Since the leader is always at
+             * the front of the sorted set, we'll just pick off hosts from the back of the
+             * set.
              */
             String host = avail.last();
             avail.remove(host);
@@ -243,15 +250,15 @@ public class ProcessingState extends State {
     }
 
     /**
-     * Adds bucket indices to {@link HostBucket} objects. Buckets that are
-     * unassigned or assigned to a host that does not appear within the map are
-     * re-assigned to a host that appears within the map.
+     * Adds bucket indices to {@link HostBucket} objects. Buckets that are unassigned or
+     * assigned to a host that does not appear within the map are re-assigned to a host
+     * that appears within the map.
      * 
      * @param bucket2host bucket assignments
      * @param host2data maps a host name to its {@link HostBucket}
      */
     private void addIndicesToHostBuckets(String[] bucket2host, Map<String, HostBucket> host2data) {
-        LinkedList<Integer> nullBuckets = new LinkedList<Integer>();
+        LinkedList<Integer> nullBuckets = new LinkedList<>();
 
         for (int x = 0; x < bucket2host.length; ++x) {
             String host = bucket2host[x];
@@ -274,10 +281,9 @@ public class ProcessingState extends State {
     }
 
     /**
-     * Assigns null buckets (i.e., those having no assignment) to available
-     * hosts.
+     * Assigns null buckets (i.e., those having no assignment) to available hosts.
      * 
-     * @param buckets available hosts
+     * @param buckets buckets that still need to be assigned to hosts
      * @param coll collection of current host-bucket assignments
      */
     private void assignNullBuckets(Queue<Integer> buckets, Collection<HostBucket> coll) {
@@ -295,9 +301,9 @@ public class ProcessingState extends State {
     }
 
     /**
-     * Re-balances the buckets, taking from those that have a larger count and
-     * giving to those that have a smaller count. Populates an output array with
-     * the new assignments.
+     * Re-balances the buckets, taking from those that have a larger count and giving to
+     * those that have a smaller count. Populates an output array with the new
+     * assignments.
      * 
      * @param coll current bucket assignment
      * @param bucket2host array to be populated with the new assignments
@@ -349,7 +355,7 @@ public class ProcessingState extends State {
     /**
      * Tracks buckets that have been assigned to a host.
      */
-    public static class HostBucket implements Comparable<HostBucket> {
+    protected static class HostBucket implements Comparable<HostBucket> {
         /**
          * Host to which the buckets have been assigned.
          */
@@ -395,8 +401,8 @@ public class ProcessingState extends State {
         }
 
         /**
-         * Compares host buckets, first by the number of buckets, and then by
-         * the host name.
+         * Compares host buckets, first by the number of buckets, and then by the host
+         * name.
          */
         @Override
         public final int compareTo(HostBucket other) {
@@ -406,5 +412,15 @@ public class ProcessingState extends State {
             }
             return d;
         }
+
+        @Override
+        public final int hashCode() {
+            throw new UnsupportedOperationException("HostBucket cannot be hashed");
+        }
+
+        @Override
+        public final boolean equals(Object obj) {
+            throw new UnsupportedOperationException("cannot compare HostBuckets");
+        }
     }
 }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/QueryState.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/QueryState.java
index 57521960..9045165b 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/QueryState.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/QueryState.java
@@ -26,26 +26,31 @@ import org.onap.policy.drools.pooling.message.BucketAssignments;
 import org.onap.policy.drools.pooling.message.Identification;
 import org.onap.policy.drools.pooling.message.Leader;
 import org.onap.policy.drools.pooling.message.Offline;
-
-// TODO add logging
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
- * The Query state. In this state, the host waits for the other hosts to
- * identify themselves. Eventually, a leader should come forth. If not, it will
- * transition to the active or inactive state, depending on whether or not it
- * has an assignment in the current bucket assignments. The other possibility is
- * that it may <i>become</i> the leader, in which case it will also transition
- * to the active state.
+ * The Query state. In this state, the host waits for the other hosts to identify
+ * themselves. Eventually, a leader should come forth. If not, it will transition to the
+ * active or inactive state, depending on whether or not it has an assignment in the
+ * current bucket assignments. The other possibility is that it may <i>become</i> the
+ * leader, in which case it will also transition to the active state.
  */
 public class QueryState extends ProcessingState {
 
+    private static final Logger logger = LoggerFactory.getLogger(QueryState.class);
+
     /**
-     * Hosts that have sent an "Identification" message. Always includes this
-     * host.
+     * Hosts that have sent an "Identification" message. Always includes this host.
      */
     private TreeSet<String> alive = new TreeSet<>();
 
     /**
+     * {@code True} if we saw our own Identification method, {@code false} otherwise.
+     */
+    private boolean sawSelfIdent = false;
+
+    /**
      * 
      * @param mgr
      */
@@ -71,44 +76,42 @@ public class QueryState extends ProcessingState {
     private void awaitIdentification() {
 
         /*
-         * Once we've waited long enough for all Identification messages to
-         * arrive, become the leader, assuming we should.
+         * Once we've waited long enough for all Identification messages to arrive, become
+         * the leader, assuming we should.
          */
 
-        schedule(getProperties().getIdentificationMs(), xxx -> {
+        schedule(getProperties().getIdentificationMs(), () -> {
+
+            if (!sawSelfIdent) {
+                // didn't see our identification
+                logger.error("missed our own Ident message on topic {}", getTopic());
+                return internalTopicFailed();
 
-            if (isLeader()) {
+            } else if (isLeader()) {
                 // "this" host is the new leader
+                logger.info("this host is the new leader for topic {}", getTopic());
                 return becomeLeader(alive);
 
             } else if (hasAssignment()) {
                 /*
-                 * this host is not the new leader, but it does have an
-                 * assignment - return to the active state while we wait for the
-                 * leader
+                 * this host is not the new leader, but it does have an assignment -
+                 * return to the active state while we wait for the leader
                  */
+                logger.info("no new leader on topic {}", getTopic());
                 return goActive();
 
             } else {
                 // not the leader and no assignment yet
+                logger.info("no new leader on topic {}", getTopic());
                 return goInactive();
             }
         });
     }
 
     /**
-     * Remains in this state.
-     */
-    @Override
-    public State goQuery() {
-        return null;
-    }
-
-    /**
      * Determines if this host has an assignment in the CURRENT assignments.
      * 
-     * @return {@code true} if this host has an assignment, {@code false}
-     *         otherwise
+     * @return {@code true} if this host has an assignment, {@code false} otherwise
      */
     protected boolean hasAssignment() {
         BucketAssignments asgn = getAssignments();
@@ -116,53 +119,73 @@ public class QueryState extends ProcessingState {
     }
 
     @Override
+    public State goQuery() {
+        return null;
+    }
+
+    @Override
     public State process(Identification msg) {
 
-        recordInfo(msg.getSource(), msg.getAssignments());
+        if (getHost().equals(msg.getSource())) {
+            logger.info("saw our own Ident message on topic {}", getTopic());
+            sawSelfIdent = true;
+
+        } else {
+            logger.info("received Ident message from {} on topic {}", msg.getSource(), getTopic());
+            recordInfo(msg.getSource(), msg.getAssignments());
+        }
 
         return null;
     }
 
     /**
-     * If the message leader is better than the leader we have, then go active
-     * with it. Otherwise, simply treat it like an {@link Identification}
-     * message.
+     * If the message leader is better than the leader we have, then go active with it.
+     * Otherwise, simply treat it like an {@link Identification} message.
      */
     @Override
     public State process(Leader msg) {
-        BucketAssignments asgn = msg.getAssignments();
-        if (asgn == null) {
+        if (!isValid(msg)) {
             return null;
         }
 
-        // ignore Leader messages from ourself
         String source = msg.getSource();
-        if (source == null || source.equals(getHost())) {
-            return null;
-        }
-
-        // the new leader must equal the source
-        if (!source.equals(asgn.getLeader())) {
-            return null;
-        }
+        BucketAssignments asgn = msg.getAssignments();
 
-        // go active, if this has a better leader than the one we have
-        if (source.compareTo(getLeader()) < 0) {
-            return super.process(msg);
+        // go active, if this has a leader that's the same or better than the one we have
+        if (source.compareTo(getLeader()) <= 0) {
+            logger.warn("leader with {} on topic {}", source, getTopic());
+            return goActive(asgn);
         }
 
         /*
-         * The message does not have an acceptable leader, but we'll still
-         * record its info.
+         * The message does not have an acceptable leader, but we'll still record its
+         * info.
          */
-        recordInfo(msg.getSource(), msg.getAssignments());
+        logger.info("record leader info from {} on topic {}", source, getTopic());
+        recordInfo(source, asgn);
+
+        return null;
+    }
+
+    @Override
+    public State process(Offline msg) {
+        String host = msg.getSource();
+
+        if (host != null && !host.equals(getHost())) {
+            logger.warn("host {} offline on topic {}", host, getTopic());
+            alive.remove(host);
+            setLeader(alive.first());
+
+        } else {
+            logger.info("ignored offline message from {} on topic {}", msg.getSource(), getTopic());
+        }
 
         return null;
     }
 
     /**
-     * Records info from a message, adding the source host name to
-     * {@link #alive}, and updating the bucket assignments.
+     * Records info from a message, adding the source host name to {@link #alive}, and
+     * updating the bucket assignments.
      * 
      * @param source the message's source host
      * @param assignments assignments, or {@code null}
@@ -181,29 +204,18 @@ public class QueryState extends ProcessingState {
         // record assignments, if we don't have any yet
         BucketAssignments current = getAssignments();
         if (current == null) {
+            logger.info("received initial assignments on topic {}", getTopic());
             setAssignments(assignments);
             return;
         }
 
         /*
-         * Record assignments, if the new assignments have a better (i.e.,
-         * lesser) leader.
+         * Record assignments, if the new assignments have a better (i.e., lesser) leader.
          */
         String curldr = current.getLeader();
-        if (curldr == null || curldr.compareTo(assignments.getLeader()) > 0) {
+        if (curldr == null || assignments.getLeader().compareTo(curldr) < 0) {
+            logger.info("use new assignments from {} on topic {}", source, getTopic());
             setAssignments(assignments);
         }
     }
-
-    @Override
-    public State process(Offline msg) {
-        String host = msg.getSource();
-
-        if (host != null && !host.equals(getHost())) {
-            alive.remove(host);
-            setLeader(alive.first());
-        }
-
-        return null;
-    }
 }
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StartState.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StartState.java
index decbdfda..a978e245 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StartState.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StartState.java
@@ -28,19 +28,19 @@ import static org.onap.policy.drools.pooling.state.FilterUtils.makeOr;
 import java.util.Map;
 import org.onap.policy.drools.pooling.PoolingManager;
 import org.onap.policy.drools.pooling.message.Heartbeat;
-import org.onap.policy.drools.pooling.message.Identification;
-import org.onap.policy.drools.pooling.message.Leader;
 import org.onap.policy.drools.pooling.message.Message;
-import org.onap.policy.drools.pooling.message.Offline;
-import org.onap.policy.drools.pooling.message.Query;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
- * The start state. Upon entry, a heart beat is generated and the event filter
- * is changed to look for just that particular message. Once the message is
- * seen, it goes into the {@link QueryState}.
+ * The start state. Upon entry, a heart beat is generated and the event filter is changed
+ * to look for just that particular message. Once the message is seen, it goes into the
+ * {@link QueryState}.
  */
 public class StartState extends State {
 
+    private static final Logger logger = LoggerFactory.getLogger(StartState.class);
+
     /**
      * Time stamp inserted into the heart beat message.
      */
@@ -69,54 +69,28 @@ public class StartState extends State {
 
         publish(getHost(), makeHeartbeat(hbTimestampMs));
 
-        schedule(getProperties().getStartHeartbeatMs(), xxx -> internalTopicFailed());
+        schedule(getProperties().getStartHeartbeatMs(), () -> {
+            logger.error("missed heartbeat on topic {}", getTopic());
+            return internalTopicFailed();
+        });
     }
 
     /**
-     * Transitions to the query state if the heart beat originated from this
-     * host and its time stamp matches.
+     * Transitions to the query state if the heart beat originated from this host and its
+     * time stamp matches.
      */
     @Override
     public State process(Heartbeat msg) {
         if (msg.getTimestampMs() == hbTimestampMs && getHost().equals(msg.getSource())) {
             // saw our own heart beat - transition to query state
+            logger.info("saw our own heartbeat on topic {}", getTopic());
             publish(makeQuery());
             return goQuery();
-        }
-
-        return null;
-    }
-
-    /**
-     * Discards the message.
-     */
-    @Override
-    public State process(Identification msg) {
-        return null;
-    }
-
-    /**
-     * Processes the assignments, but remains in the current state.
-     */
-    @Override
-    public State process(Leader msg) {
-        super.process(msg);
-        return null;
-    }
 
-    /**
-     * Discards the message.
-     */
-    @Override
-    public State process(Offline msg) {
-        return null;
-    }
+        } else {
+            logger.info("ignored old heartbeat message from {} on topic {}", msg.getSource(), getTopic());
+        }
 
-    /**
-     * Discards the message.
-     */
-    @Override
-    public State process(Query msg) {
         return null;
     }
 
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/State.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/State.java
index 1e3a907e..421b9225 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/State.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/State.java
@@ -26,7 +26,7 @@ import static org.onap.policy.drools.pooling.state.FilterUtils.makeOr;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
-import java.util.concurrent.ScheduledFuture;
+import org.onap.policy.drools.pooling.CancellableScheduledTask;
 import org.onap.policy.drools.pooling.PoolingManager;
 import org.onap.policy.drools.pooling.PoolingProperties;
 import org.onap.policy.drools.pooling.message.BucketAssignments;
@@ -37,16 +37,19 @@ import org.onap.policy.drools.pooling.message.Leader;
 import org.onap.policy.drools.pooling.message.Message;
 import org.onap.policy.drools.pooling.message.Offline;
 import org.onap.policy.drools.pooling.message.Query;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * A state in the finite state machine.
  * <p>
- * A state may have several timers associated with it, which must be cancelled
- * whenever the state is changed. Assumes that timers are not continuously added
- * to the same state.
+ * A state may have several timers associated with it, which must be cancelled whenever
+ * the state is changed. Assumes that timers are not continuously added to the same state.
  */
 public abstract class State {
 
+    private static final Logger logger = LoggerFactory.getLogger(State.class);
+
     /**
      * Host pool manager.
      */
@@ -55,7 +58,7 @@ public abstract class State {
     /**
      * Timers added by this state.
      */
-    private final List<ScheduledFuture<?>> timers = new LinkedList<>();
+    private final List<CancellableScheduledTask> timers = new LinkedList<>();
 
     /**
      * 
@@ -66,9 +69,9 @@ public abstract class State {
     }
 
     /**
-     * Gets the server-side filter to use when polling the DMaaP internal topic.
-     * The default method returns a filter that accepts messages on the admin
-     * channel and on the host's own channel.
+     * Gets the server-side filter to use when polling the DMaaP internal topic. The
+     * default method returns a filter that accepts messages on the admin channel and on
+     * the host's own channel.
      * 
      * @return the server-side filter to use.
      */
@@ -80,25 +83,15 @@ public abstract class State {
     /**
      * Cancels the timers added by this state.
      */
-    public void cancelTimers() {
-        for (ScheduledFuture<?> fut : timers) {
-            fut.cancel(false);
-        }
+    public final void cancelTimers() {
+        timers.forEach(timer -> timer.cancel());
     }
 
     /**
-     * Starts the state.
+     * Starts the state. The default method simply logs a message and returns.
      */
     public void start() {
-
-    }
-
-    /**
-     * Indicates that the finite state machine is stopping. Sends an "offline"
-     * message to the other hosts.
-     */
-    public void stop() {
-        publish(makeOffline());
+        logger.info("entered {} for topic {}", getClass().getSimpleName(), getTopic());
     }
 
     /**
@@ -106,7 +99,7 @@ public abstract class State {
      * 
      * @return the new state
      */
-    public State goStart() {
+    public final State goStart() {
         return mgr.goStart();
     }
 
@@ -124,7 +117,7 @@ public abstract class State {
      * 
      * @return the new state
      */
-    public State goActive() {
+    public final State goActive() {
         return mgr.goActive();
     }
 
@@ -138,13 +131,14 @@ public abstract class State {
     }
 
     /**
-     * Processes a message. The default method passes it to the manager to
-     * handle and returns {@code null}.
+     * Processes a message. The default method passes it to the manager to handle and
+     * returns {@code null}.
      * 
      * @param msg message to be processed
      * @return the new state, or {@code null} if the state is unchanged
      */
     public State process(Forward msg) {
+        logger.info("received Forward message from {} on topic {}", msg.getSource(), getTopic());
         mgr.handle(msg);
         return null;
     }
@@ -156,6 +150,7 @@ public abstract class State {
      * @return the new state, or {@code null} if the state is unchanged
      */
     public State process(Heartbeat msg) {
+        logger.info("ignored heartbeat message from {} on topic {}", msg.getSource(), getTopic());
         return null;
     }
 
@@ -166,41 +161,54 @@ public abstract class State {
      * @return the new state, or {@code null} if the state is unchanged
      */
     public State process(Identification msg) {
+        logger.info("ignored ident message from {} on topic {}", msg.getSource(), getTopic());
         return null;
     }
 
     /**
-     * Processes a message. If this host has a new assignment, then it
-     * transitions to the active state. Otherwise, it transitions to the
-     * inactive state.
+     * Processes a message. The default method copies the assignments and then returns
+     * {@code null}.
      * 
      * @param msg message to be processed
      * @return the new state, or {@code null} if the state is unchanged
      */
     public State process(Leader msg) {
+        if (isValid(msg)) {
+            logger.info("extract assignments from Leader message from {} on topic {}", msg.getSource(), getTopic());
+            startDistributing(msg.getAssignments());
+        }
+
+        return null;
+    }
+
+    /**
+     * Determines if a message is valid and did not originate from this host.
+     * 
+     * @param msg message to be validated
+     * @return {@code true} if the message is valid, {@code false} otherwise
+     */
+    protected boolean isValid(Leader msg) {
         BucketAssignments asgn = msg.getAssignments();
         if (asgn == null) {
-            return null;
+            logger.warn("Leader message from {} has no assignments for topic {}", msg.getSource(), getTopic());
+            return false;
         }
 
+        // ignore Leader messages from ourself
         String source = msg.getSource();
-        if (source == null) {
-            return null;
+        if (source == null || source.equals(getHost())) {
+            logger.debug("ignore Leader message from {} for topic {}", msg.getSource(), getTopic());
+            return false;
         }
 
         // the new leader must equal the source
-        if (source.equals(asgn.getLeader())) {
-            startDistributing(asgn);
-
-            if (asgn.hasAssignment(getHost())) {
-                return goActive();
+        boolean result = source.equals(asgn.getLeader());
 
-            } else {
-                return goInactive();
-            }
+        if (!result) {
+            logger.warn("Leader message from {} has an invalid assignment for topic {}", msg.getSource(), getTopic());
         }
 
-        return null;
+        return result;
     }
 
     /**
@@ -210,6 +218,7 @@ public abstract class State {
      * @return the new state, or {@code null} if the state is unchanged
      */
     public State process(Offline msg) {
+        logger.info("ignored offline message from {} on topic {}", msg.getSource(), getTopic());
         return null;
     }
 
@@ -220,6 +229,7 @@ public abstract class State {
      * @return the new state, or {@code null} if the state is unchanged
      */
     public State process(Query msg) {
+        logger.info("ignored Query message from {} on topic {}", msg.getSource(), getTopic());
         return null;
     }
 
@@ -228,7 +238,7 @@ public abstract class State {
      * 
      * @param msg message to be published
      */
-    protected void publish(Identification msg) {
+    protected final void publish(Identification msg) {
         mgr.publishAdmin(msg);
     }
 
@@ -237,7 +247,7 @@ public abstract class State {
      * 
      * @param msg message to be published
      */
-    protected void publish(Leader msg) {
+    protected final void publish(Leader msg) {
         mgr.publishAdmin(msg);
     }
 
@@ -246,7 +256,7 @@ public abstract class State {
      * 
      * @param msg message to be published
      */
-    protected void publish(Offline msg) {
+    protected final void publish(Offline msg) {
         mgr.publishAdmin(msg);
     }
 
@@ -255,7 +265,7 @@ public abstract class State {
      * 
      * @param msg message to be published
      */
-    protected void publish(Query msg) {
+    protected final void publish(Query msg) {
         mgr.publishAdmin(msg);
     }
 
@@ -265,7 +275,7 @@ public abstract class State {
      * @param channel
      * @param msg message to be published
      */
-    protected void publish(String channel, Forward msg) {
+    protected final void publish(String channel, Forward msg) {
         mgr.publish(channel, msg);
     }
 
@@ -275,7 +285,7 @@ public abstract class State {
      * @param channel
      * @param msg message to be published
      */
-    protected void publish(String channel, Heartbeat msg) {
+    protected final void publish(String channel, Heartbeat msg) {
         mgr.publish(channel, msg);
     }
 
@@ -284,7 +294,7 @@ public abstract class State {
      * 
      * @param assignments
      */
-    protected void startDistributing(BucketAssignments assignments) {
+    protected final void startDistributing(BucketAssignments assignments) {
         if (assignments != null) {
             mgr.startDistributing(assignments);
         }
@@ -296,7 +306,7 @@ public abstract class State {
      * @param delayMs
      * @param task
      */
-    protected void schedule(long delayMs, StateTimerTask task) {
+    protected final void schedule(long delayMs, StateTimerTask task) {
         timers.add(mgr.schedule(delayMs, task));
     }
 
@@ -307,7 +317,7 @@ public abstract class State {
      * @param delayMs
      * @param task
      */
-    protected void scheduleWithFixedDelay(long initialDelayMs, long delayMs, StateTimerTask task) {
+    protected final void scheduleWithFixedDelay(long initialDelayMs, long delayMs, StateTimerTask task) {
         timers.add(mgr.scheduleWithFixedDelay(initialDelayMs, delayMs, task));
     }
 
@@ -316,7 +326,7 @@ public abstract class State {
      * 
      * @return a new {@link InactiveState}
      */
-    protected State internalTopicFailed() {
+    protected final State internalTopicFailed() {
         publish(makeOffline());
         mgr.internalTopicFailed();
 
@@ -330,16 +340,25 @@ public abstract class State {
      * 
      * @return a new message
      */
-    protected Heartbeat makeHeartbeat(long timestampMs) {
+    protected final Heartbeat makeHeartbeat(long timestampMs) {
         return new Heartbeat(getHost(), timestampMs);
     }
 
     /**
+     * Makes an Identification message.
+     * 
+     * @return a new message
+     */
+    protected Identification makeIdentification() {
+        return new Identification(getHost(), getAssignments());
+    }
+
+    /**
      * Makes an "offline" message.
      * 
      * @return a new message
      */
-    protected Offline makeOffline() {
+    protected final Offline makeOffline() {
         return new Offline(getHost());
     }
 
@@ -348,7 +367,7 @@ public abstract class State {
      * 
      * @return a new message
      */
-    protected Query makeQuery() {
+    protected final Query makeQuery() {
         return new Query(getHost());
     }
 
diff --git a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StateTimerTask.java b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StateTimerTask.java
index bd388b4e..346d4496 100644
--- a/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StateTimerTask.java
+++ b/feature-pooling-dmaap/src/main/java/org/onap/policy/drools/pooling/state/StateTimerTask.java
@@ -29,9 +29,8 @@ public interface StateTimerTask {
     /**
      * Fires the timer.
      * 
-     * @param arg always {@code null}
      * @return the new state, or {@code null} if the state is unchanged
      */
-    public State fire(Void arg);
+    public State fire();
 
 }