[POLICY-72] replace openecomp for drools-pdp

Change-Id: I8aa8e32d3ba10f7c655b50e97aaf6865514d4777
Signed-off-by: Guo Ruijing <ruijing.guo@intel.com>

6 files changed, 1672 insertions, 0 deletions

diff --git a/policy-core/src/main/java/org/onap/policy/drools/core/PolicyContainer.java b/policy-core/src/main/java/org/onap/policy/drools/core/PolicyContainer.java
new file mode 100644
index 00000000..cf94bfcb
--- /dev/null
+++ b/policy-core/src/main/java/org/onap/policy/drools/core/PolicyContainer.java
@@ -0,0 +1,848 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * policy-core
+ * ================================================================================
+ * Copyright (C) 2017 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.core;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.kie.api.KieBase;
+import org.kie.api.KieServices;
+import org.kie.api.builder.KieScanner;
+import org.kie.api.builder.Message;
+import org.kie.api.builder.ReleaseId;
+import org.kie.api.builder.Results;
+import org.kie.api.runtime.KieContainer;
+import org.kie.api.runtime.KieSession;
+import org.onap.policy.drools.properties.Startable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This class is a wrapper around 'KieContainer', which adds the ability
+ * to automatically create and track KieSession instances.
+ */
+public class PolicyContainer implements Startable
+{
+	// get an instance of logger 
+  private static Logger logger = LoggerFactory.getLogger(PolicyContainer.class);	
+  // 'KieServices' singleton
+  static private KieServices kieServices = KieServices.Factory.get();
+
+  // set of all 'PolicyContainer' instances
+  static private HashSet<PolicyContainer> containers =
+	new HashSet<PolicyContainer>();
+
+  // maps feature objects to per-PolicyContainer data
+  private ConcurrentHashMap<Object, Object> adjuncts =
+	new ConcurrentHashMap<Object, Object>();
+
+  // 'KieContainer' associated with this 'PolicyContainer'
+  private KieContainer kieContainer;
+
+  // indicates whether the PolicyContainer is 'started'
+  // (started = sessions created, threads running)
+  private volatile boolean isStarted = false;
+
+  // maps session name into the associated 'PolicySession' instance
+  private HashMap<String, PolicySession> sessions =
+	new HashMap<String, PolicySession>();
+
+  // if not null, this is a 'KieScanner' looking for updates
+  private KieScanner scanner = null;
+  
+  // indicates whether the scanner has been started
+  // (it can block for a long time)
+  private boolean scannerStarted = false;
+
+  /**
+   * uses 'groupId', 'artifactId' and 'version', and fetches the associated
+   * artifact and remaining dependencies from the Maven repository to create
+   * the 'PolicyContainer' and associated 'KieContainer'.
+   *
+   * An exception occurs if the creation of the 'KieContainer' fails.
+   *
+   * @param groupId the 'groupId' associated with the artifact
+   * @param artifactId the artifact name
+   * @param version a comma-separated list of possible versions
+   */
+  public PolicyContainer(String groupId, String artifactId, String version)
+  {
+	this(kieServices.newReleaseId(groupId, artifactId, version));
+  }
+
+  /**
+   * uses the 'groupId', 'artifactId' and 'version' information in 'ReleaseId',
+   * and fetches the associated artifact and remaining dependencies from the
+   * Maven repository to create the 'PolicyContainer' and associated
+   * 'KieContainer'.
+   *
+   * An exception occurs if the creation of the 'KieContainer' fails.
+   *
+   * @param releaseId indicates the artifact that is to be installed in this
+   *	container
+   */
+  public PolicyContainer(ReleaseId releaseId)
+  {
+	if (releaseId.getVersion().contains(","))
+	  {
+		// this is actually a comma-separated list of release ids
+		releaseId = loadArtifact(releaseId.getGroupId(),
+								 releaseId.getArtifactId(),
+								 releaseId.getVersion());
+	  }
+	else
+	  {
+		kieContainer = kieServices.newKieContainer(releaseId);
+	  }
+	synchronized(containers)
+	  {
+		if(releaseId != null){
+		   logger.info("Add a new kieContainer in containers: releaseId: " + releaseId.toString());
+		}else{
+		   logger.warn("input releaseId is null");
+		}
+		containers.add(this);
+	  }
+	// 'startScanner(releaseId)' was called at this point, but we have seen
+	// at least one case where the Drools container was repeatedly updated
+	// every 60 seconds. It isn't clear what conditions resulted in this
+	// behavior, so the call was removed. If needed, it can be explicitly
+	// called from a feature.
+  }
+
+  /**
+   * Load an artifact into a new KieContainer. This method handles the
+   * case where the 'version' is actually a comma-separated list of
+   * versions.
+   *
+   * @param groupId the 'groupId' associated with the artifact
+   * @param artifactId the artifact name
+   * @param version a comma-separated list of possible versions
+   */
+  private ReleaseId loadArtifact
+	(String groupId, String artifactId, String version)
+  {
+	String[] versions = version.split(",");
+	if (versions.length > 1)
+	  {
+		logger.info("Multiple KieContainer versions are specified: "
+						  + version);
+	  }
+
+	// indicates a 'newKieContainer' call failed
+	RuntimeException exception = null;
+
+	// set prior to every 'newKieContainer' invocation
+	// (if we are able to create the container, it will be the last
+	// one that was successful)
+	ReleaseId releaseId = null;
+	for (String ver : versions)
+	  {
+		try
+		  {
+			// Create a 'ReleaseId' object describing the artifact, and
+			// create a 'KieContainer' based upon it.
+			logger.info("Create new KieContainer start, version = "
+							  + ver + " ...");
+
+			releaseId = kieServices.newReleaseId(groupId, artifactId, ver);
+			kieContainer = kieServices.newKieContainer(releaseId);
+
+			// clear any exception, and break out of the loop
+			exception = null;
+			break;
+		  }
+		catch (RuntimeException e)
+		  {
+			exception = e;
+		  }
+	  }
+	if (exception != null)
+	  {
+		// all of the 'newKieContainer' invocations failed -- throw the
+		// most recent exception
+		throw(exception);
+	  }
+	return(releaseId);
+  }
+
+  /**
+   * @return the name of the container, which is the String equivalent of
+   * the 'ReleaseId'. It has the form:
+   *
+   *	(groupId + ":" + artifactId + ":" + version)
+   *
+   * Note that the name changes after a successful call to 'updateToVersion',
+   * although typically only the 'version' part changes.
+   */
+  public String getName()
+  {
+	return(kieContainer.getReleaseId().toString());
+  }
+
+  /**
+   * @return the associated 'KieContainer' instance
+   */
+  public KieContainer getKieContainer()
+  {
+	return(kieContainer);
+  }
+
+  /**
+   * @return the 'ClassLoader' associated with the 'KieContainer' instance
+   */
+  public ClassLoader getClassLoader()
+  {
+	return(kieContainer.getClassLoader());
+  }
+
+  /**
+   * @return the Maven GroupId of the top-level artifact wrapped
+   *	by the container.
+   */
+  public String getGroupId()
+  {
+	return(kieContainer.getReleaseId().getGroupId());
+  }
+
+  /**
+   * @return the Maven ArtifactId of the top-level artifact wrapped
+   *	by the container.
+   */
+  public String getArtifactId()
+  {
+	return(kieContainer.getReleaseId().getArtifactId());
+  }
+
+  /**
+   * @return the version of the top-level artifact wrapped by the
+   *	container (this may change as updates occur)
+   */
+  public String getVersion()
+  {
+	return(kieContainer.getReleaseId().getVersion());
+  }
+
+  /**
+   * Fetch the named 'PolicySession'.
+   *
+   * @param name the name of the KieSession (which is also the name of
+   *	the associated PolicySession)
+   * @return a PolicySession if found, 'null' if not
+   */
+  public PolicySession getPolicySession(String name)
+  {
+	return(sessions.get(name));
+  }
+
+  /**
+   * Internal method to create a PolicySession, possibly restoring it
+   * from persistent storage.
+   *
+   * @param name of the KieSession and PolicySession
+   * @param kieBaseName name of the associated 'KieBase' instance
+   * @return a new or existing PolicySession, or 'null' if not found
+   */
+  private PolicySession activatePolicySession(String name, String kieBaseName)
+  {
+	synchronized(sessions)
+	  {
+		logger.info("activatePolicySession:name :" + name);
+		PolicySession session = sessions.get(name);
+		if (session == null)
+		  {
+			KieSession kieSession = null;
+
+			// loop through all of the features, and give each one
+			// a chance to create the 'KieSession'
+			for (PolicySessionFeatureAPI feature :
+				   PolicySessionFeatureAPI.impl.getList())
+			  {
+				try
+				  {
+					if ((kieSession = feature.activatePolicySession
+						 (this, name, kieBaseName)) != null)
+					  break;
+				  }
+				catch (Exception e)
+				  {
+					logger.error("ERROR: Feature API: "
+								 + feature.getClass().getName(), e);
+				  }
+			  }
+
+			// if none of the features created the session, create one now
+			if (kieSession == null)
+			  {
+				kieSession = kieContainer.newKieSession(name);
+			  }
+
+			if (kieSession != null)
+			  {
+				// creation of 'KieSession' was successful - build
+				// a PolicySession
+				session = new PolicySession(name, this, kieSession);
+				sessions.put(name, session);
+
+				// notify features
+				for (PolicySessionFeatureAPI feature :
+					   PolicySessionFeatureAPI.impl.getList())
+				  {
+					try
+					  {
+						feature.newPolicySession(session);
+					  }
+					catch (Exception e)
+					  {
+						logger.error("ERROR: Feature API: "
+									 + feature.getClass().getName(), e);
+					  }
+				  }
+				logger.info("activatePolicySession:new session was added in sessions with name " + name);
+			  }
+		  }
+		logger.info("activatePolicySession:session - "
+						  + (session == null ? "null" : session.getFullName())
+						  + " is returned.");
+		return(session);
+	  }
+  }
+
+  /**
+   * This creates a 'PolicySession' instance within this 'PolicyContainer',
+   * and ties it to the specified 'KieSession'. 'name' must not currently
+   * exist within the 'PolicyContainer', and the 'KieBase' object associated
+   * with 'KieSession' must belong to the 'KieContainer'. This method provides
+   * a way for 'KieSession' instances that are created programmatically to fit
+   * into this framework.
+   *
+   * @param name the name for the new 'PolicySession'
+   * @param kieSession a 'KieSession' instance, that will be included in
+   *	this infrastructure
+   * @return the new 'PolicySession'
+   * @throws IllegalArgumentException if 'kieSession' does not reside within
+   *	this container
+   * @throws IllegalStateException if a 'PolicySession' already exists
+   *	with this name
+   */
+  public PolicySession adoptKieSession(String name, KieSession kieSession)
+	throws IllegalArgumentException, IllegalStateException
+  {
+
+	if(name == null){
+		logger.warn("adoptKieSession:input name is null");
+		throw(new IllegalArgumentException
+				  ("KieSession input name is null "
+				   + getName()));
+	}else if(kieSession == null){
+		logger.warn("adoptKieSession:input kieSession is null");
+		throw(new IllegalArgumentException
+				  ("KieSession '" + name + "' is null "
+				   + getName()));
+	}else {
+		logger.info("adoptKieSession:name: " + name + " kieSession: " + kieSession);
+	}
+	// fetch KieBase, and verify it belongs to this KieContainer
+	boolean match = false;
+	KieBase kieBase = kieSession.getKieBase();
+	logger.info("adoptKieSession:kieBase: " + kieBase);
+	for (String kieBaseName : kieContainer.getKieBaseNames())
+	  {
+		logger.info("adoptKieSession:kieBaseName: " + kieBaseName);
+		if (kieBase == kieContainer.getKieBase(kieBaseName))
+		  {
+			match = true;
+			break;
+		  }
+	  }
+	logger.info("adoptKieSession:match " + match);
+	// if we don't have a match yet, the last chance is to look at the
+	// default KieBase, if it exists
+	if (!match && kieBase != kieContainer.getKieBase())
+	  {
+		throw(new IllegalArgumentException
+			  ("KieSession '" + name + "' does not reside within container "
+			   + getName()));
+	  }
+
+	synchronized (sessions)
+	  {
+		if (sessions.get(name) != null)
+		  {
+			throw(new IllegalStateException
+				  ("PolicySession '" + name + "' already exists"));
+		  }
+
+		// create the new 'PolicySession', add it to the table,
+		// and return the object to the caller
+		logger.info("adoptKieSession:create a new policySession with name " + name);
+		PolicySession policySession =
+		  new PolicySession(name, this, kieSession);
+		sessions.put(name, policySession);
+
+		// notify features
+		for (PolicySessionFeatureAPI feature :
+			   PolicySessionFeatureAPI.impl.getList())
+		  {
+			try
+			  {
+				feature.newPolicySession(policySession);
+			  }
+			catch (Exception e)
+			  {
+				logger.error("ERROR: Feature API: "
+							 + feature.getClass().getName(), e);
+			  }
+		  }
+		return(policySession);
+	  }
+  }
+
+  /**
+   * This call 'KieContainer.updateToVersion()', and returns the associated
+   * response as a String. If successful, the name of this 'PolicyContainer'
+   * changes to match the new version.
+   *
+   * @param newVersion this is the version to update to (the 'groupId'
+   *	and 'artifactId' remain the same)
+   * @return the list of messages associated with the update (not sure if
+   *	this can be 'null', or how to determine success/failure)
+   */
+  public String updateToVersion(String newVersion)
+  {
+	ReleaseId releaseId = kieContainer.getReleaseId();
+	Results results = this.updateToVersion
+	  (kieServices.newReleaseId(releaseId.getGroupId(),
+								releaseId.getArtifactId(),
+								newVersion));
+
+	List<Message> messages = (results == null ? null : results.getMessages());
+	return(messages == null ? null : messages.toString());
+  }
+
+  /**
+   * This calls 'KieContainer.updateToVersion()', and returns the associated
+   * response. If successful, the name of this 'PolicyContainer' changes to
+   * match the new version.
+   *
+   * @param releaseId the new artifact (usually new version) to be installed
+   * @return the 'Results' parameter from 'KieContainer.updateToVersion'
+   */
+  public Results updateToVersion(ReleaseId releaseId)
+  {
+    if(releaseId == null){
+	   logger.warn("updateToVersion:input releaseId is null");
+    }else {
+       logger.info("updateToVersion:releaseId " + releaseId.toString());
+    }
+
+	// notify all 'PolicySession' instances
+	Results results = kieContainer.updateToVersion(releaseId);
+	for (PolicySession session : sessions.values())
+	  {
+		session.updated();
+	  }
+
+	return(results);
+  }
+
+  /**
+   * @return all existing 'PolicyContainer' instances
+   */
+  public static Collection<PolicyContainer> getPolicyContainers()
+  {
+	synchronized(containers)
+	  {
+		return(new HashSet<PolicyContainer>(containers));
+	  }
+  }
+
+  /**
+   * @return all of the 'PolicySession' instances
+   */
+  public Collection<PolicySession> getPolicySessions()
+  {
+	// KLUDGE WARNING: this is a temporary workaround -- if there are
+	// no features, we don't have persistence, and 'activate' is never
+	// called. In this case, make sure the container is started.
+	if (PolicySessionFeatureAPI.impl.getList().size() == 0)
+	  {
+		start();
+	  }
+
+	// return current set of PolicySessions
+	synchronized(sessions)
+	  {
+		return(new HashSet<PolicySession>(sessions.values()));
+	  }
+  }
+
+  /**
+   * This method will start a 'KieScanner' (if not currently running),
+   * provided that the ReleaseId version is 'LATEST' or 'RELEASE',
+   * or refers to a SNAPSHOT version.
+   *
+   * @param releaseId the release id used to create the container
+   */
+  public synchronized void startScanner(ReleaseId releaseId)
+  {
+	String version = releaseId.getVersion();
+	if (scannerStarted == false && scanner == null && version != null
+		&& (version.equals("LATEST") || version.equals("RELEASE")
+			|| version.endsWith("-SNAPSHOT")))
+	  {
+		// create the scanner, and poll at 60 second intervals
+		try
+		  {
+			scannerStarted = true;
+
+			// start this in a separate thread -- it can block for a long time
+			new Thread("Scanner Starter " + getName())
+			{
+			  public void run()
+			  {
+				scanner = kieServices.newKieScanner(kieContainer);
+				scanner.start(60000L);
+			  }
+			}.start();
+		  }
+		catch (Exception e)
+		  {
+			// sometimes the scanner initialization fails for some reason
+			logger.error("startScanner error", e);
+		  }
+	  }
+  }
+
+  /**
+   * Insert a fact into a specific named session
+   *
+   * @param name this is the session name
+   * @param object this is the fact to be inserted into the session
+   * @return 'true' if the named session was found, 'false' if not
+   */
+  public boolean insert(String name, Object object)
+  {
+	// TODO: Should the definition of 'name' be expanded to include an
+	// alternate entry point as well? For example, 'name.entryPoint' (or
+	// something other than '.' if that is a problem).
+	synchronized (sessions)
+	  {
+		PolicySession session = sessions.get(name);
+		if (session != null)
+		  {
+			session.getKieSession().insert(object);
+			return(true);
+		  }
+	  }
+	return(false);
+  }
+
+  /**
+   * Insert a fact into all sessions associated with this container
+   *
+   * @param object this is the fact to be inserted into the sessions
+   * @return 'true' if the fact was inserted into at least one session,
+   *	'false' if not
+   */
+  public boolean insertAll(Object object)
+  {
+	boolean rval = false;
+	synchronized (sessions)
+	  {
+		for (PolicySession session : sessions.values())
+		  {
+			session.getKieSession().insert(object);
+			rval = true;
+		  }
+	  }
+	return(rval);
+  }
+
+  /*************************/
+  /* 'Startable' interface */
+  /*************************/
+
+  /**
+   * {@inheritDoc}
+   */
+  public synchronized boolean start()
+  {
+	if (!isStarted)
+	  {
+		// This will create all 'PolicySession' instances specified in the
+		// 'kmodule.xml' file that don't exist yet
+		for (String kieBaseName : kieContainer.getKieBaseNames())
+		  {
+			for (String kieSessionName :
+				   kieContainer.getKieSessionNamesInKieBase(kieBaseName))
+			  {
+				// if the 'PolicySession' does not currently exist, this method
+				// call will attempt to create it
+				PolicySession session =
+				  activatePolicySession(kieSessionName, kieBaseName);
+				if (session != null)
+				  {
+					session.startThread();
+				  }
+			  }
+		  }
+		isStarted = true;
+	  }
+	return(true);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public synchronized boolean stop()
+  {
+	if (isStarted)
+	  {
+		Collection<PolicySession> localSessions;
+
+		synchronized (sessions)
+		  {
+			// local set containing all of the sessions
+			localSessions = new HashSet<PolicySession>(sessions.values());
+
+			// clear the 'name->session' map in 'PolicyContainer'
+			sessions.clear();
+		  }
+		for (PolicySession session : localSessions)
+		  {
+			// stop session thread
+			session.stopThread();
+
+			// free KieSession resources
+			session.getKieSession().dispose();
+
+			// notify features
+			for (PolicySessionFeatureAPI feature :
+				   PolicySessionFeatureAPI.impl.getList())
+			  {
+				try
+				  {
+					feature.disposeKieSession(session);
+				  }
+				catch (Exception e)
+				  {
+					logger.error("ERROR: Feature API: "
+								 + feature.getClass().getName(), e);
+				  }
+			  }
+		  }
+		isStarted = false;
+	  }
+	return(true);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public synchronized void shutdown()
+  {
+	// Note that this method does not call 'destroy' on the 'KieSession'
+	// instances, which would remove any associated information in persistent
+	// storage. Should it do this?
+
+	stop();
+	synchronized(containers)
+	  {
+		containers.remove(this);
+	  }
+
+	// How do we free the resources associated with the KieContainer?
+	// Is garbage collection sufficient?
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public boolean isAlive()
+  {
+	return(isStarted);
+  }
+
+  /*************************/
+
+  /**
+   * This method is similar to 'shutdown', but it also frees any persistence
+   * resources as well.
+   */
+  public synchronized void destroy()
+  {
+	// we need all KieSession instances running in order to free
+	// resources associated with persistence
+	start();
+	Collection<PolicySession> localSessions;
+
+	synchronized (sessions)
+	  {
+		// local set containing all of the sessions
+		localSessions = new HashSet<PolicySession>(sessions.values());
+
+		// clear the 'name->session' map in 'PolicyContainer'
+		sessions.clear();
+	  }
+	for (PolicySession session : localSessions)
+	  {
+		// stop session thread
+		session.stopThread();
+
+		// free KieSession resources
+		session.getKieSession().destroy();
+
+		// notify features
+		for (PolicySessionFeatureAPI feature :
+			   PolicySessionFeatureAPI.impl.getList())
+		  {
+			try
+			  {
+				feature.destroyKieSession(session);
+			  }
+			catch (Exception e)
+			  {
+				logger.error("ERROR: Feature API: "
+							 + feature.getClass().getName(), e);
+			  }
+		  }
+	  }
+	isStarted = false;
+
+	synchronized(containers)
+	  {
+		containers.remove(this);
+	  }
+
+	// How do we free the resources associated with the KieContainer?
+	// Is garbage collection sufficient?
+  }
+
+  /**
+   * This method is called when the host goes from the 'standby->active' state.
+   */
+  static public void activate()
+  {
+	// start all of the 'PolicyContainer' instances
+	for (PolicyContainer container : containers)
+	  {
+		try
+		  {
+			container.start();
+		  }
+		catch (Exception e)
+		  {
+			logger.error("PolicyContainer.start() error in activate", e);
+		  }
+	  }
+  }
+
+  /**
+   * This method is called when the host goes from the 'active->standby' state.
+   */
+  static public void deactivate()
+  {
+	// deactivate all of the 'PolicyContainer' instances
+	for (PolicyContainer container : containers)
+	  {
+		try
+		  {
+			container.stop();
+		  }
+		catch (Exception e)
+		  {
+			logger.error("PolicyContainer.start() error in deactivate", e);
+		  }
+	  }
+  }
+
+  /**
+   * This method does the following:
+   *
+   *	1) Initializes logging
+   *	2) Starts the DroolsPDP Integrity Monitor
+   *	3) Initilaizes persistence
+   *
+   * It no longer reads in properties files, o creates 'PolicyContainer'
+   * instances.
+   *
+   * @param args standard 'main' arguments, which are currently ignored
+   */
+  public static void globalInit(String args[])
+  {
+	String configDir = "config";
+	logger.info("PolicyContainer.main: configDir=" + configDir);
+
+	// invoke 'globalInit' on all of the features
+	for (PolicySessionFeatureAPI feature :
+		   PolicySessionFeatureAPI.impl.getList())
+	  {
+		try
+		  {
+			feature.globalInit(args, configDir);
+		  }
+		catch (Exception e)
+		  {
+			logger.error("ERROR: Feature API: "
+						 + feature.getClass().getName(), e);
+		  }
+	  }
+  }
+	
+  /**
+   * Fetch the adjunct object associated with a given feature
+   *
+   * @param object this is typically the singleton feature object that is
+   *	used as a key, but it might also be useful to use nested objects
+   *	within the feature as keys.
+   * @return a feature-specific object associated with the key, or 'null'
+   *	if it is not found.
+   */
+  public Object getAdjunct(Object object)
+  {
+	return(adjuncts.get(object));
+  }
+
+  /**
+   * Store the adjunct object associated with a given feature
+   *
+   * @param object this is typically the singleton feature object that is
+   *	used as a key, but it might also be useful to use nested objects
+   *	within the feature as keys.
+   * @param value a feature-specific object associated with the key, or 'null'
+   *	if the feature-specific object should be removed
+   */
+  public void setAdjunct(Object object, Object value)
+  {
+	if (value == null)
+	  {
+		adjuncts.remove(object);
+	  }
+	else
+	  {
+		adjuncts.put(object, value);
+	  }
+  }
+}
diff --git a/policy-core/src/main/java/org/onap/policy/drools/core/PolicySession.java b/policy-core/src/main/java/org/onap/policy/drools/core/PolicySession.java
new file mode 100644
index 00000000..77e16804
--- /dev/null
+++ b/policy-core/src/main/java/org/onap/policy/drools/core/PolicySession.java
@@ -0,0 +1,576 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * policy-core
+ * ================================================================================
+ * Copyright (C) 2017 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.core;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.kie.api.event.rule.AfterMatchFiredEvent;
+import org.kie.api.event.rule.AgendaEventListener;
+import org.kie.api.event.rule.AgendaGroupPoppedEvent;
+import org.kie.api.event.rule.AgendaGroupPushedEvent;
+import org.kie.api.event.rule.BeforeMatchFiredEvent;
+import org.kie.api.event.rule.MatchCancelledEvent;
+import org.kie.api.event.rule.MatchCreatedEvent;
+import org.kie.api.event.rule.ObjectDeletedEvent;
+import org.kie.api.event.rule.ObjectInsertedEvent;
+import org.kie.api.event.rule.ObjectUpdatedEvent;
+import org.kie.api.event.rule.RuleFlowGroupActivatedEvent;
+import org.kie.api.event.rule.RuleFlowGroupDeactivatedEvent;
+import org.kie.api.event.rule.RuleRuntimeEventListener;
+import org.kie.api.runtime.KieSession;
+import org.onap.policy.drools.core.jmx.PdpJmx;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+
+/**
+ * This class is a wrapper around 'KieSession', which adds the following:
+ *
+ * 1) A thread running 'KieSession.fireUntilHalt()'
+ * 2) Access to UEB
+ * 3) Logging of events
+ */
+public class PolicySession
+  implements AgendaEventListener, RuleRuntimeEventListener
+{
+	// get an instance of logger 
+  private static Logger  logger = LoggerFactory.getLogger(PolicySession.class);		
+  // name of the 'PolicySession' and associated 'KieSession'
+  private String name;
+
+  // the associated 'PolicyContainer', which may have additional
+  // 'PolicySession' instances in addition to this one
+  private PolicyContainer container;
+
+  // maps feature objects to per-PolicyContainer data
+  private ConcurrentHashMap<Object, Object> adjuncts =
+	new ConcurrentHashMap<Object, Object>();
+
+  // associated 'KieSession' instance
+  private KieSession kieSession;
+
+  // if not 'null', this is the thread model processing the 'KieSession'
+  private ThreadModel threadModel = null;
+
+  // supports 'getCurrentSession()' method
+  static private ThreadLocal<PolicySession> policySession =
+	new ThreadLocal<PolicySession>();
+
+  /**
+   * Internal constructor - create a 'PolicySession' instance
+   *
+   * @param name the name of this 'PolicySession' (and 'kieSession')
+   * @param container the 'PolicyContainer' instance containing this session
+   * @param kieSession the associated 'KieSession' instance
+   */
+  protected PolicySession(String name,
+						  PolicyContainer container, KieSession kieSession)
+  {
+	this.name = name;
+	this.container = container;
+	this.kieSession = kieSession;
+	kieSession.addEventListener((AgendaEventListener)this);
+	kieSession.addEventListener((RuleRuntimeEventListener)this);
+  }
+
+  /**
+   * @return the 'PolicyContainer' object containing this session
+   */
+  public PolicyContainer getPolicyContainer()
+  {
+	return(container);
+  }
+
+  /**
+   * @return the associated 'KieSession' instance
+   */
+  public KieSession getKieSession()
+  {
+	return(kieSession);
+  }
+
+  /**
+   * @return the local name of this session, which should either match the
+   * name specified in 'kmodule.xml' file associated with this session, or the
+   * name passed on the 'PolicyContainer.adoptKieSession' method.
+   */
+  public String getName()
+  {
+	return(name);
+  }
+
+  /**
+   * @return the 'PolicyContainer' name, followed by ':', followed by the
+   * local name of the session. It should be useful in log messages.
+   */
+  public String getFullName()
+  {
+	return(container.getName() + ":" + name);
+  }
+
+  /**
+   * If no 'ThreadModel' is currently running, this method will create one,
+   * and invoke it's 'start()' method. Features implementing
+   * 'PolicySessionFeatureAPI.selectThreadModel(...)' get a chance to create
+   * the ThreadModel instance.
+   */
+  public synchronized void startThread()
+  {
+	if (threadModel == null)
+	  {
+		// loop through all of the features, and give each one
+		// a chance to create the 'ThreadModel'
+		for (PolicySessionFeatureAPI feature :
+			   PolicySessionFeatureAPI.impl.getList())
+		  {
+			try
+			  {
+				if ((threadModel = feature.selectThreadModel(this)) != null)
+				  break;
+			  }
+			catch (Exception e)
+			  {
+				logger.error("ERROR: Feature API: "
+							 + feature.getClass().getName(), e);
+			  }
+		  }		
+		if (threadModel == null)
+		  {
+			// no feature created a ThreadModel -- select the default
+			threadModel = new DefaultThreadModel(this);
+		  }
+		logger.info("starting ThreadModel for session " + getFullName());
+		threadModel.start();
+	  }
+  }
+
+  /**
+   * If a 'ThreadModel' is currently running, this calls the 'stop()' method,
+   * and sets the 'threadModel' reference to 'null'.
+   */
+  public synchronized void stopThread()
+  {
+	if (threadModel != null)
+	  {
+		threadModel.stop();
+		threadModel = null;
+	  }
+  }
+
+  /**
+   * Notification that 'updateToVersion' was called on the container
+   */
+  void updated()
+  {
+	if (threadModel != null)
+	  {
+		// notify the 'ThreadModel', which may change one or more Thread names
+		threadModel.updated();
+	  }
+  }
+
+  /**
+   * Set this 'PolicySession' instance as the one associated with the
+   * currently-running thread.
+   */
+  public void setPolicySession()
+  {
+	// this sets a 'ThreadLocal' variable
+	policySession.set(this);
+  }
+
+  /**
+   * @return the 'PolicySession' instance associated with the current thread
+   *	(Note that this only works if the current thread is the one running
+   *	'kieSession.fireUntilHalt()'.)
+   */
+  public static PolicySession getCurrentSession()
+  {
+	return(policySession.get());
+  }
+	
+  /**
+   * Fetch the adjunct object associated with a given feature
+   *
+   * @param object this is typically the singleton feature object that is
+   *	used as a key, but it might also be useful to use nested objects
+   *	within the feature as keys.
+   * @return a feature-specific object associated with the key, or 'null'
+   *	if it is not found.
+   */
+  public Object getAdjunct(Object object)
+  {
+	return(adjuncts.get(object));
+  }
+
+  /**
+   * Store the adjunct object associated with a given feature
+   *
+   * @param object this is typically the singleton feature object that is
+   *	used as a key, but it might also be useful to use nested objects
+   *	within the feature as keys.
+   * @param value a feature-specific object associated with the key, or 'null'
+   *	if the feature-specific object should be removed
+   */
+  public void setAdjunct(Object object, Object value)
+  {
+	if (value == null)
+	  {
+		adjuncts.remove(object);
+	  }
+	else
+	  {
+		adjuncts.put(object, value);
+	  }
+  }
+
+  /***********************************/
+  /* 'AgendaEventListener' interface */
+  /***********************************/
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void afterMatchFired(AfterMatchFiredEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("afterMatchFired: " + getFullName()
+					 + ": AgendaEventListener.afterMatchFired(" + event + ")");
+	  }
+	PdpJmx.getInstance().ruleFired();
+ }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void afterRuleFlowGroupActivated(RuleFlowGroupActivatedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+	logger.debug("afterRuleFlowGroupActivated: " + getFullName()
+				 + ": AgendaEventListener.afterRuleFlowGroupActivated("
+				 + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void afterRuleFlowGroupDeactivated
+	(RuleFlowGroupDeactivatedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("afterRuleFlowGroupDeactivated: " + getFullName()
+					 + ": AgendaEventListener.afterRuleFlowGroupDeactivated("
+					 + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void agendaGroupPopped(AgendaGroupPoppedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("agendaGroupPopped: " + getFullName()
+					 + ": AgendaEventListener.agendaGroupPopped("
+					 + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void agendaGroupPushed(AgendaGroupPushedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("agendaGroupPushed: " + getFullName()
+					 + ": AgendaEventListener.agendaGroupPushed("
+					 + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void beforeMatchFired(BeforeMatchFiredEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("beforeMatchFired: " + getFullName()
+					 + ": AgendaEventListener.beforeMatchFired("
+					 + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void beforeRuleFlowGroupActivated
+	(RuleFlowGroupActivatedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("beforeRuleFlowGroupActivated: " + getFullName()
+					 + ": AgendaEventListener.beforeRuleFlowGroupActivated("
+					 + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void beforeRuleFlowGroupDeactivated
+	(RuleFlowGroupDeactivatedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("beforeRuleFlowGroupDeactivated: " + getFullName()
+					 + ": AgendaEventListener.beforeRuleFlowGroupDeactivated("
+					 + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void matchCancelled(MatchCancelledEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("matchCancelled: " + getFullName()
+					 + ": AgendaEventListener.matchCancelled(" + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void matchCreated(MatchCreatedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("matchCreated: " + getFullName()
+					 + ": AgendaEventListener.matchCreated(" + event + ")");
+	  }
+  }
+
+  /****************************************/
+  /* 'RuleRuntimeEventListener' interface */
+  /****************************************/
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void objectDeleted(ObjectDeletedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("objectDeleted: " + getFullName()
+					 + ": AgendaEventListener.objectDeleted(" + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void objectInserted(ObjectInsertedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("objectInserted: " + getFullName()
+					 + ": AgendaEventListener.objectInserted(" + event + ")");
+	  }
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public void objectUpdated(ObjectUpdatedEvent event)
+  {
+	if (logger.isDebugEnabled())
+	  {
+		logger.debug("objectUpdated: " + getFullName()
+					 + ": AgendaEventListener.objectUpdated(" + event + ")");
+	  }
+  }
+
+  /* ============================================================ */
+
+  /**
+   * This interface helps support the ability for features to choose the
+   * thread or threads that processes the 'KieSession'.
+   */
+  public interface ThreadModel
+  {
+	/**
+	 * Start the thread or threads that do the 'KieSession' processing
+	 */
+	public void start();
+
+	/**
+	 * Stop the thread or threads that do the 'KieSession' processing
+	 */
+	public void stop();
+
+	/**
+	 * This method is called to notify the running session that
+	 * 'KieContainer.updateToVersion(...)' has been called (meaning the
+	 * full name of this session has changed).
+	 */
+	default public void updated() {}
+  }
+
+  /* ============================================================ */
+
+  /**
+   * This 'ThreadModel' variant uses 'KieSession.fireUntilHalt()'.
+   */
+  public static class DefaultThreadModel implements Runnable,ThreadModel
+  {
+	// session associated with this persistent thread
+	PolicySession session;
+
+	// the session thread
+	Thread thread;
+
+	// controls whether the thread loops or terminates
+	volatile boolean repeat = true;
+
+	/**
+	 * Constructor - initialize 'session' and create thread
+	 *
+	 * @param session the 'PolicySession' instance
+	 */
+	public DefaultThreadModel(PolicySession session)
+	{
+	  this.session = session;
+	  thread = new Thread(this,getThreadName());
+	}
+
+	/**
+	 * @return the String to use as the thread name
+	 */
+	private String getThreadName()
+	{
+	  return("Session " + session.getFullName());
+	}
+
+	/***************************/
+	/* 'ThreadModel' interface */
+	/***************************/
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	  public void start()
+	{
+	  repeat = true;
+	  thread.start();
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	  public void stop()
+	{
+	  repeat = false;
+
+	  // this should cause the thread to exit		
+	  session.getKieSession().halt();
+	  try
+		{
+		  // wait up to 10 seconds for the thread to stop
+		  thread.join(10000);
+
+		  // one more interrupt, just in case the 'kieSession.halt()'
+		  // didn't work for some reason
+		  thread.interrupt();
+		}
+	  catch (Exception e)
+		{
+		  logger.error("stopThread in thread.join error");
+		}
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	  public void updated()
+	{
+	  // the container artifact has been updated -- adjust the thread name
+	  thread.setName(getThreadName());
+	}
+
+	/************************/
+	/* 'Runnable' interface */
+	/************************/
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	  public void run()
+	{
+	  // set thread local variable
+	  session.setPolicySession();
+
+	  // We want to continue looping, despite any exceptions that occur
+	  // while rules are fired.
+	  KieSession kieSession = session.getKieSession();
+	  while (repeat)
+		{
+		  try
+			{
+			  kieSession.fireUntilHalt();
+
+			  // if we fall through, it means 'KieSession.halt()' was called,
+			  // but this may be a result of 'KieScanner' doing an update
+			}
+		  catch (Exception | LinkageError e)
+			{
+			  logger.error("startThread error in kieSession.fireUntilHalt", e);						
+			}
+		}
+	  logger.info("fireUntilHalt() returned");
+	}
+  }
+}
diff --git a/policy-core/src/main/java/org/onap/policy/drools/core/PolicySessionFeatureAPI.java b/policy-core/src/main/java/org/onap/policy/drools/core/PolicySessionFeatureAPI.java
new file mode 100644
index 00000000..6777eb59
--- /dev/null
+++ b/policy-core/src/main/java/org/onap/policy/drools/core/PolicySessionFeatureAPI.java
@@ -0,0 +1,107 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * policy-core
+ * ================================================================================
+ * Copyright (C) 2017 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.core;
+
+import org.kie.api.runtime.KieSession;
+import org.onap.policy.drools.utils.OrderedService;
+import org.onap.policy.drools.utils.OrderedServiceImpl;
+
+/**
+ * This interface provides a way to invoke optional features at various
+ * points in the code. At appropriate points in the
+ * application, the code iterates through this list, invoking these optional
+ * methods. Most of the methods here are notification only -- these tend to
+ * return a 'void' value. In other cases, such as 'activatePolicySession',
+ * may 
+ */
+public interface PolicySessionFeatureAPI extends OrderedService
+{
+  /**
+   * 'FeatureAPI.impl.getList()' returns an ordered list of objects
+   * implementing the 'FeatureAPI' interface.
+   */
+  static public OrderedServiceImpl<PolicySessionFeatureAPI> impl =
+	new OrderedServiceImpl<PolicySessionFeatureAPI>(PolicySessionFeatureAPI.class);
+
+  /**
+   * This method is called during initialization at a point right after
+   * 'PolicyContainer' initialization has completed.
+   *
+   * @param args standard 'main' arguments, which are currently ignored
+   * @param configDir the relative directory containing configuration files
+   */
+  default public void globalInit(String args[], String configDir) {}
+
+  /**
+   * This method is used to create a 'KieSession' as part of a
+   * 'PolicyContainer'. The caller of this method will iterate over the
+   * implementers of this interface until one returns a non-null value.
+   *
+   * @param policyContainer the 'PolicyContainer' instance containing this
+   *	session
+   * @param name the name of the KieSession (which is also the name of
+   *	the associated PolicySession)
+   * @param kieBaseName the name of the 'KieBase' instance containing
+   *	this session
+   * @return a new KieSession, if one was created, or 'null' if not
+   *	(this depends on the capabilities and state of the object implementing
+   *	this interface)
+   */
+  default public KieSession activatePolicySession
+	(PolicyContainer policyContainer, String name, String kieBaseName)
+  {
+	return(null);
+  }
+
+  /**
+   * This method is called after a new 'PolicySession' has been initialized,
+   * and linked to the 'PolicyContainer'.
+   *
+   * @param policySession the new 'PolicySession' instance
+   */
+  default public void newPolicySession(PolicySession policySession) {}
+
+  /**
+   * This method is called to select the 'ThreadModel' instance associated
+   * with a 'PolicySession' instance.
+   */
+  default public PolicySession.ThreadModel selectThreadModel
+	(PolicySession session)
+  {
+	return(null);
+  }
+
+  /**
+   * This method is called after 'KieSession.dispose()' is called
+   *
+   * @param policySession the 'PolicySession' object that wrapped the
+   *	'KieSession'
+   */
+  default public void disposeKieSession(PolicySession policySession) {}
+
+  /**
+   * This method is called after 'KieSession.destroy()' is called
+   *
+   * @param policySession the 'PolicySession' object that wrapped the
+   *	'KieSession'
+   */
+  default public void destroyKieSession(PolicySession policySession) {}
+}
diff --git a/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmx.java b/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmx.java
new file mode 100644
index 00000000..d3cf2e9d
--- /dev/null
+++ b/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmx.java
@@ -0,0 +1,47 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * policy-core
+ * ================================================================================
+ * Copyright (C) 2017 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.core.jmx;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+public class PdpJmx implements PdpJmxMBean  {
+
+	private static PdpJmx instance = new PdpJmx();
+	private final AtomicLong updates = new AtomicLong();
+	private final AtomicLong actions = new AtomicLong();
+
+	public static PdpJmx getInstance() {
+		return instance;
+	}
+	
+	public long getUpdates(){
+		return updates.longValue();
+	}
+	public long getRulesFired(){
+		return actions.longValue();
+	}
+	public void updateOccured(){
+		updates.incrementAndGet();
+	}
+	public void ruleFired(){
+		actions.incrementAndGet();
+	}
+}
diff --git a/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmxListener.java b/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmxListener.java
new file mode 100644
index 00000000..ceb7049e
--- /dev/null
+++ b/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmxListener.java
@@ -0,0 +1,67 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * policy-core
+ * ================================================================================
+ * Copyright (C) 2017 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.core.jmx;
+
+import java.lang.management.ManagementFactory;
+
+import javax.management.InstanceAlreadyExistsException;
+import javax.management.InstanceNotFoundException;
+import javax.management.MBeanRegistrationException;
+import javax.management.MBeanServer;
+import javax.management.MalformedObjectNameException;
+import javax.management.NotCompliantMBeanException;
+import javax.management.ObjectName;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class PdpJmxListener {
+
+	public static final Logger logger = LoggerFactory.getLogger(PdpJmxListener.class);
+	
+	public static void stop() {
+		final MBeanServer server = ManagementFactory.getPlatformMBeanServer();
+		try {
+			server.unregisterMBean(new ObjectName("PolicyEngine:type=PdpJmx"));
+		} catch (MBeanRegistrationException | InstanceNotFoundException
+				| MalformedObjectNameException e) {
+			logger.error("PdpJmxListener.stop(): " + 
+				         "Could not unregister PolicyEngine:type=PdpJmx MBean " +
+					     "with the MBean server", e);
+		}
+		
+	}
+
+	
+	public static void start() {
+		final MBeanServer server = ManagementFactory.getPlatformMBeanServer();
+		try {
+			server.registerMBean(PdpJmx.getInstance(), new ObjectName("PolicyEngine:type=PdpJmx"));
+		} catch (InstanceAlreadyExistsException | MBeanRegistrationException
+				| NotCompliantMBeanException | MalformedObjectNameException e) {
+			logger.error("PdpJmxListener.start(): " + 
+			             "Could not unregister PolicyEngine:type=PdpJmx MBean " +
+				         "with the MBean server", e);
+		}
+		
+	}
+
+}
diff --git a/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmxMBean.java b/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmxMBean.java
new file mode 100644
index 00000000..37a9e4dc
--- /dev/null
+++ b/policy-core/src/main/java/org/onap/policy/drools/core/jmx/PdpJmxMBean.java
@@ -0,0 +1,27 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * policy-core
+ * ================================================================================
+ * Copyright (C) 2017 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.core.jmx;
+
+public interface PdpJmxMBean {
+
+	public long getRulesFired();
+	public long getUpdates();
+}