Handle participant register,deregister,update messages

Send ParticipantRegister, ParticipantDeregister and ParticipantUpdateAck
from participant to controlloop runtime
Receive ParticipantRegisterAck, ParticipantDeregisterAck and
ParticipantUpdate messages from controlloop runtime

Issue-ID: POLICY-3414
Signed-off-by: Sirisha_Manchikanti <sirisha.manchikanti@est.tech>
Change-Id: Ifb3c4fa64bdd2d50ec2302b35f342847f4994c5d

11 files changed, 399 insertions, 26 deletions

diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/ParticipantIntermediaryApi.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/ParticipantIntermediaryApi.java
index a87299bdc..7e448dc15 100644
--- a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/ParticipantIntermediaryApi.java
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/ParticipantIntermediaryApi.java
@@ -46,6 +46,16 @@ public interface ParticipantIntermediaryApi {
     void registerControlLoopElementListener(ControlLoopElementListener controlLoopElementListener);
 
     /**
+     * Send participant register message to controlloop runtime.
+     */
+    void sendParticipantRegister();
+
+    /**
+     * Send participant deregister message to controlloop runtime.
+     */
+    void sendParticipantDeregister();
+
+    /**
      * Get participants loops from the intermediary API.
      *
      * @param name the participant name, null for all
@@ -114,5 +124,4 @@ public interface ParticipantIntermediaryApi {
      * @param elementStatistics the updated statistics
      */
     void updateControlLoopElementStatistics(UUID id, ClElementStatistics elementStatistics);
-
 }
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/impl/ParticipantIntermediaryApiImpl.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/impl/ParticipantIntermediaryApiImpl.java
index 838f47544..9652f1a8d 100644
--- a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/impl/ParticipantIntermediaryApiImpl.java
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/api/impl/ParticipantIntermediaryApiImpl.java
@@ -63,6 +63,16 @@ public class ParticipantIntermediaryApiImpl implements ParticipantIntermediaryAp
     }
 
     @Override
+    public void sendParticipantRegister() {
+        participantHandler.sendParticipantRegister();
+    }
+
+    @Override
+    public void sendParticipantDeregister() {
+        participantHandler.sendParticipantDeregister();
+    }
+
+    @Override
     public List<Participant> getParticipants(String name, String version) {
         return List.of(participantHandler.getParticipant(name, version));
     }
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/MessageSender.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/MessageSender.java
index 6926bc30b..1bfce1374 100644
--- a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/MessageSender.java
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/MessageSender.java
@@ -30,9 +30,12 @@ import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoop
 import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopElement;
 import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoops;
 import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ParticipantStatistics;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantDeregister;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantRegister;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantResponseDetails;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantResponseStatus;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantStatus;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantUpdateAck;
 import org.onap.policy.clamp.controlloop.participant.intermediary.api.ControlLoopElementListener;
 import org.onap.policy.clamp.controlloop.participant.intermediary.handler.ParticipantHandler;
 import org.onap.policy.models.base.PfModelException;
@@ -47,7 +50,7 @@ public class MessageSender extends TimerTask implements Closeable {
     private static final Logger LOGGER = LoggerFactory.getLogger(MessageSender.class);
 
     private final ParticipantHandler participantHandler;
-    private final ParticipantStatusPublisher publisher;
+    private final ParticipantMessagePublisher publisher;
     private ScheduledExecutorService timerPool;
 
     /**
@@ -57,7 +60,7 @@ public class MessageSender extends TimerTask implements Closeable {
      * @param publisher the publisher to use for sending messages
      * @param interval time interval to send Participant Status periodic messages
      */
-    public MessageSender(ParticipantHandler participantHandler, ParticipantStatusPublisher publisher,
+    public MessageSender(ParticipantHandler participantHandler, ParticipantMessagePublisher publisher,
             long interval) {
         this.participantHandler = participantHandler;
         this.publisher = publisher;
@@ -127,11 +130,38 @@ public class MessageSender extends TimerTask implements Closeable {
 
         status.setControlLoops(controlLoops);
 
-        publisher.send(status);
+        publisher.sendParticipantStatus(status);
     }
 
     /**
-     * Update ControlLoopElement statistics. The control loop elements listening will be 
+     * Send a ParticipantRegister message for this participant.
+     *
+     * @param message the participantRegister message
+     */
+    public void sendParticipantRegister(ParticipantRegister message) {
+        publisher.sendParticipantRegister(message);
+    }
+
+    /**
+     * Send a ParticipantDeregister message for this participant.
+     *
+     * @param message the participantDeRegister message
+     */
+    public void sendParticipantDeregister(ParticipantDeregister message) {
+        publisher.sendParticipantDeregister(message);
+    }
+
+    /**
+     * Send a ParticipantUpdateAck message for this participant update.
+     *
+     * @param message the participantUpdateAck message
+     */
+    public void sendParticipantUpdateAck(ParticipantUpdateAck message) {
+        publisher.sendParticipantUpdateAck(message);
+    }
+
+    /**
+     * Update ControlLoopElement statistics. The control loop elements listening will be
      * notified to retrieve statistics from respective controlloop elements, and controlloopelements
      * data on the handler will be updated.
      *
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantAckListener.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantAckListener.java
new file mode 100644
index 000000000..262b21630
--- /dev/null
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantAckListener.java
@@ -0,0 +1,57 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.intermediary.comm;
+
+import java.util.function.Consumer;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantAckMessage;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantMessage;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantRegisterAck;
+import org.onap.policy.clamp.controlloop.participant.intermediary.handler.ParticipantHandler;
+import org.onap.policy.common.endpoints.event.comm.Topic.CommInfrastructure;
+import org.onap.policy.common.endpoints.listeners.ScoListener;
+import org.onap.policy.common.utils.coder.StandardCoderObject;
+
+/**
+ * Abstract Listener for Participant Ack messages sent by runtime.
+ */
+public abstract class ParticipantAckListener<T extends ParticipantAckMessage> extends ScoListener<T> {
+
+    private final ParticipantHandler participantHandler;
+    private final Consumer<T> consumer;
+
+    /**
+     * Constructs the object.
+     *
+     * @param clazz class of message this handles
+     * @param participantHandler ParticipantHandler
+     * @param consumer function that handles the message
+     */
+    protected ParticipantAckListener(Class<T> clazz, ParticipantHandler participantHandler, Consumer<T> consumer) {
+        super(clazz);
+        this.participantHandler = participantHandler;
+        this.consumer = consumer;
+    }
+
+    @Override
+    public void onTopicEvent(CommInfrastructure infra, String topic, StandardCoderObject sco, T message) {
+        consumer.accept(message);
+    }
+}
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantDeregisterAckListener.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantDeregisterAckListener.java
new file mode 100644
index 000000000..e20f481f8
--- /dev/null
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantDeregisterAckListener.java
@@ -0,0 +1,42 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.intermediary.comm;
+
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantDeregisterAck;
+import org.onap.policy.clamp.controlloop.participant.intermediary.handler.ParticipantHandler;
+import org.springframework.stereotype.Component;
+
+/**
+ * Listener for Participant Deregister Ack messages sent by runtime.
+ *
+ */
+@Component
+public class ParticipantDeregisterAckListener extends ParticipantAckListener<ParticipantDeregisterAck> {
+
+    /**
+     * Constructs the object.
+     *
+     * @param participantHandler the handler for managing the state of the participant
+     */
+    public ParticipantDeregisterAckListener(final ParticipantHandler participantHandler) {
+        super(ParticipantDeregisterAck.class, participantHandler, participantHandler::handleParticipantDeregisterAck);
+    }
+}
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantStatusPublisher.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantMessagePublisher.java
index 78b998453..9e1b84620 100644
--- a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantStatusPublisher.java
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantMessagePublisher.java
@@ -21,7 +21,10 @@
 package org.onap.policy.clamp.controlloop.participant.intermediary.comm;
 
 import java.util.List;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantDeregister;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantRegister;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantStatus;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantUpdateAck;
 import org.onap.policy.common.endpoints.event.comm.TopicSink;
 import org.onap.policy.common.endpoints.event.comm.client.TopicSinkClient;
 import org.slf4j.Logger;
@@ -31,17 +34,20 @@ import org.slf4j.LoggerFactory;
  * This class is used to send Participant Status messages to clamp using TopicSinkClient.
  *
  */
-public class ParticipantStatusPublisher {
-    private static final Logger LOGGER = LoggerFactory.getLogger(ParticipantStatusPublisher.class);
+public class ParticipantMessagePublisher {
+    private static final Logger LOGGER = LoggerFactory.getLogger(ParticipantMessagePublisher.class);
 
     private final TopicSinkClient topicSinkClient;
 
     /**
-     * Constructor for instantiating ParticipantStatusPublisher.
+     * Constructor for instantiating ParticipantMessagePublisher.
      *
      * @param topicSinks the topic sinks
      */
-    public ParticipantStatusPublisher(List<TopicSink> topicSinks) {
+    public ParticipantMessagePublisher(List<TopicSink> topicSinks) {
+        if (topicSinks.size() != 1) {
+            throw new IllegalArgumentException("Configuration unsupported, Topic sinks greater than 1");
+        }
         this.topicSinkClient = new TopicSinkClient(topicSinks.get(0));
     }
 
@@ -50,8 +56,38 @@ public class ParticipantStatusPublisher {
      *
      * @param participantStatus the Participant Status
      */
-    public void send(final ParticipantStatus participantStatus) {
+    public void sendParticipantStatus(final ParticipantStatus participantStatus) {
         topicSinkClient.send(participantStatus);
         LOGGER.debug("Sent Participant Status message to CLAMP - {}", participantStatus);
     }
+
+    /**
+     * Method to send Participant Status message to clamp on demand.
+     *
+     * @param participantRegister the Participant Status
+     */
+    public void sendParticipantRegister(final ParticipantRegister participantRegister) {
+        topicSinkClient.send(participantRegister);
+        LOGGER.debug("Sent Participant Register message to CLAMP - {}", participantRegister);
+    }
+
+    /**
+     * Method to send Participant Status message to clamp on demand.
+     *
+     * @param participantDeregister the Participant Status
+     */
+    public void sendParticipantDeregister(final ParticipantDeregister participantDeregister) {
+        topicSinkClient.send(participantDeregister);
+        LOGGER.debug("Sent Participant Deregister message to CLAMP - {}", participantDeregister);
+    }
+
+    /**
+     * Method to send Participant Update Ack message to runtime.
+     *
+     * @param participantUpdateAck the Participant Update Ack
+     */
+    public void sendParticipantUpdateAck(final ParticipantUpdateAck participantUpdateAck) {
+        topicSinkClient.send(participantUpdateAck);
+        LOGGER.debug("Sent Participant Update Ack message to CLAMP - {}", participantUpdateAck);
+    }
 }
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantRegisterAckListener.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantRegisterAckListener.java
new file mode 100644
index 000000000..a15a2a850
--- /dev/null
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantRegisterAckListener.java
@@ -0,0 +1,42 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.intermediary.comm;
+
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantRegisterAck;
+import org.onap.policy.clamp.controlloop.participant.intermediary.handler.ParticipantHandler;
+import org.springframework.stereotype.Component;
+
+/**
+ * Listener for Participant Register Ack messages sent by runtime.
+ *
+ */
+@Component
+public class ParticipantRegisterAckListener extends ParticipantAckListener<ParticipantRegisterAck> {
+
+    /**
+     * Constructs the object.
+     *
+     * @param participantHandler the handler for managing the state of the participant
+     */
+    public ParticipantRegisterAckListener(final ParticipantHandler participantHandler) {
+        super(ParticipantRegisterAck.class, participantHandler, participantHandler::handleParticipantRegisterAck);
+    }
+}
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantUpdateListener.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantUpdateListener.java
new file mode 100644
index 000000000..42bd52d9a
--- /dev/null
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/comm/ParticipantUpdateListener.java
@@ -0,0 +1,41 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.clamp.controlloop.participant.intermediary.comm;
+
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantUpdate;
+import org.onap.policy.clamp.controlloop.participant.intermediary.handler.ParticipantHandler;
+import org.springframework.stereotype.Component;
+
+/**
+ * Listener for Participant Update messages sent by runtime.
+ */
+@Component
+public class ParticipantUpdateListener extends ParticipantListener<ParticipantUpdate> {
+
+    /**
+     * Constructs the object.
+     *
+     * @param participantHandler the handler for managing the state of the participant
+     */
+    public ParticipantUpdateListener(final ParticipantHandler participantHandler) {
+        super(ParticipantUpdate.class, participantHandler, participantHandler::handleParticipantUpdate);
+    }
+}
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/config/BeanFactory.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/config/BeanFactory.java
index dc7d87eec..e363504a5 100644
--- a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/config/BeanFactory.java
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/config/BeanFactory.java
@@ -21,7 +21,7 @@
 package org.onap.policy.clamp.controlloop.participant.intermediary.config;
 
 import java.util.List;
-import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantStatusPublisher;
+import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantMessagePublisher;
 import org.onap.policy.clamp.controlloop.participant.intermediary.parameters.ParticipantParameters;
 import org.onap.policy.common.endpoints.event.comm.TopicEndpointManager;
 import org.onap.policy.common.endpoints.event.comm.TopicSink;
@@ -36,16 +36,16 @@ public class BeanFactory {
     private static final String[] MSG_TYPE_NAMES = {"messageType"};
 
     /**
-     * create ParticipantStatusPublisher.
+     * create ParticipantMessagePublisher.
      *
      * @param parameters the ParticipantParameters
-     * @return ParticipantStatusPublisher
+     * @return ParticipantMessagePublisher
      */
     @Bean
-    public ParticipantStatusPublisher publisher(final ParticipantParameters parameters) {
+    public ParticipantMessagePublisher publisher(final ParticipantParameters parameters) {
         List<TopicSink> topicSinks = TopicEndpointManager.getManager()
                 .addTopicSinks(parameters.getIntermediaryParameters().getClampControlLoopTopics().getTopicSinks());
-        return new ParticipantStatusPublisher(topicSinks);
+        return new ParticipantMessagePublisher(topicSinks);
     }
 
     @Bean
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/IntermediaryActivator.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/IntermediaryActivator.java
index 2d789d40d..0aa536746 100644
--- a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/IntermediaryActivator.java
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/IntermediaryActivator.java
@@ -24,10 +24,14 @@ import java.io.Closeable;
 import java.io.IOException;
 import java.util.List;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantMessageType;
+import org.onap.policy.clamp.controlloop.participant.intermediary.api.ParticipantIntermediaryApi;
 import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ControlLoopStateChangeListener;
 import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ControlLoopUpdateListener;
+import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantDeregisterAckListener;
 import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantHealthCheckListener;
+import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantRegisterAckListener;
 import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantStateChangeListener;
+import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantUpdateListener;
 import org.onap.policy.clamp.controlloop.participant.intermediary.parameters.ParticipantParameters;
 import org.onap.policy.common.endpoints.event.comm.TopicEndpointManager;
 import org.onap.policy.common.endpoints.event.comm.TopicSource;
@@ -50,14 +54,18 @@ public class IntermediaryActivator extends ServiceManagerContainer implements Cl
     // Topics from which the participant receives and to which the participant sends messages
     private List<TopicSource> topicSources;
 
+    ParticipantIntermediaryApi participantIntermediaryApi;
+
     /**
      * Instantiate the activator for participant.
      *
      * @param applicationContext ApplicationContext
      * @param parameters the ParticipantParameters
      */
-    public IntermediaryActivator(final ApplicationContext applicationContext, final ParticipantParameters parameters) {
+    public IntermediaryActivator(final ApplicationContext applicationContext, final ParticipantParameters parameters,
+            ParticipantIntermediaryApi participantIntermediaryApi) {
         this.applicationContext = applicationContext;
+        this.participantIntermediaryApi = participantIntermediaryApi;
 
         topicSources = TopicEndpointManager.getManager()
                 .addTopicSources(parameters.getIntermediaryParameters().getClampControlLoopTopics().getTopicSources());
@@ -81,6 +89,7 @@ public class IntermediaryActivator extends ServiceManagerContainer implements Cl
     public void handleContextRefreshEvent(ContextRefreshedEvent ctxRefreshedEvent) {
         if (!isAlive()) {
             start();
+            sendParticipantRegister();
         }
     }
 
@@ -92,10 +101,19 @@ public class IntermediaryActivator extends ServiceManagerContainer implements Cl
     @EventListener
     public void handleContextClosedEvent(ContextClosedEvent ctxClosedEvent) {
         if (isAlive()) {
+            sendParticipantDeregister();
             stop();
         }
     }
 
+    private void sendParticipantRegister() {
+        participantIntermediaryApi.sendParticipantRegister();
+    }
+
+    private void sendParticipantDeregister() {
+        participantIntermediaryApi.sendParticipantDeregister();
+    }
+
     /**
      * Registers the dispatcher with the topic source(s).
      */
@@ -114,6 +132,15 @@ public class IntermediaryActivator extends ServiceManagerContainer implements Cl
         msgDispatcher.register(ParticipantMessageType.PARTICIPANT_CONTROL_LOOP_UPDATE.name(),
                 applicationContext.getBean(ControlLoopUpdateListener.class));
 
+        msgDispatcher.register(ParticipantMessageType.PARTICIPANT_REGISTER_ACK.name(),
+                applicationContext.getBean(ParticipantRegisterAckListener.class));
+
+        msgDispatcher.register(ParticipantMessageType.PARTICIPANT_DEREGISTER_ACK.name(),
+                applicationContext.getBean(ParticipantDeregisterAckListener.class));
+
+        msgDispatcher.register(ParticipantMessageType.PARTICIPANT_UPDATE.name(),
+                applicationContext.getBean(ParticipantUpdateListener.class));
+
         for (final TopicSource source : topicSources) {
             source.register(msgDispatcher);
         }
diff --git a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/ParticipantHandler.java b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/ParticipantHandler.java
index 1c54658fa..a8913c1f0 100644
--- a/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/ParticipantHandler.java
+++ b/participant/participant-intermediary/src/main/java/org/onap/policy/clamp/controlloop/participant/intermediary/handler/ParticipantHandler.java
@@ -21,22 +21,32 @@
 package org.onap.policy.clamp.controlloop.participant.intermediary.handler;
 
 import java.io.Closeable;
+import java.util.LinkedHashMap;
+import java.util.Map;
 import java.util.Objects;
+import java.util.UUID;
 import lombok.Getter;
 import lombok.Setter;
+import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ControlLoopElementDefinition;
 import org.onap.policy.clamp.controlloop.models.controlloop.concepts.Participant;
 import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ParticipantHealthStatus;
 import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ParticipantState;
 import org.onap.policy.clamp.controlloop.models.controlloop.concepts.ParticipantStatistics;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantControlLoopStateChange;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantControlLoopUpdate;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantDeregister;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantDeregisterAck;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantHealthCheck;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantMessage;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantRegister;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantRegisterAck;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantResponseDetails;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantResponseStatus;
 import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantStateChange;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantUpdate;
+import org.onap.policy.clamp.controlloop.models.messages.dmaap.participant.ParticipantUpdateAck;
 import org.onap.policy.clamp.controlloop.participant.intermediary.comm.MessageSender;
-import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantStatusPublisher;
+import org.onap.policy.clamp.controlloop.participant.intermediary.comm.ParticipantMessagePublisher;
 import org.onap.policy.clamp.controlloop.participant.intermediary.parameters.ParticipantParameters;
 import org.onap.policy.models.tosca.authorative.concepts.ToscaConceptIdentifier;
 import org.slf4j.Logger;
@@ -63,13 +73,15 @@ public class ParticipantHandler implements Closeable {
     @Setter
     private ParticipantHealthStatus healthStatus = ParticipantHealthStatus.UNKNOWN;
 
+    private final Map<UUID, ControlLoopElementDefinition> clElementDefsOnThisParticipant = new LinkedHashMap<>();
+
     /**
      * Constructor, set the participant ID and sender.
      *
      * @param parameters the parameters of the participant
      * @param publisher the publisher for sending responses to messages
      */
-    public ParticipantHandler(ParticipantParameters parameters, ParticipantStatusPublisher publisher) {
+    public ParticipantHandler(ParticipantParameters parameters, ParticipantMessagePublisher publisher) {
         this.participantType = parameters.getIntermediaryParameters().getParticipantType();
         this.participantId = parameters.getIntermediaryParameters().getParticipantId();
         this.sender =
@@ -249,20 +261,87 @@ public class ParticipantHandler implements Closeable {
     /**
      * Check if a participant message applies to this participant handler.
      *
-     * @param partipantMsg the message to check
+     * @param participantMsg the message to check
      * @return true if it applies, false otherwise
      */
-    public boolean canHandle(ParticipantMessage partipantMsg) {
-        return partipantMsg.appliesTo(participantType, participantId);
+    public boolean appliesTo(ParticipantMessage participantMsg) {
+        return participantMsg.appliesTo(participantType, participantId);
     }
 
     /**
-     * Check if a participant message applies to this participant handler.
+     * Method to send ParticipantRegister message to controlloop runtime.
+     */
+    public void sendParticipantRegister() {
+        var participantRegister = new ParticipantRegister();
+        participantRegister.setParticipantId(participantId);
+        participantRegister.setParticipantType(participantType);
+
+        sender.sendParticipantRegister(participantRegister);
+    }
+
+    /**
+     * Handle a participantRegister Ack message.
      *
-     * @param partipantMsg the message to check
-     * @return true if it applies, false otherwise
+     * @param participantRegisterAckMsg the participantRegisterAck message
+     */
+    public void handleParticipantRegisterAck(ParticipantRegisterAck participantRegisterAckMsg) {
+        LOGGER.debug("ParticipantRegisterAck message received as responseTo {}",
+            participantRegisterAckMsg.getResponseTo());
+    }
+
+    /**
+     * Method to send ParticipantDeregister message to controlloop runtime.
+     */
+    public void sendParticipantDeregister() {
+        var participantDeregister = new ParticipantDeregister();
+        participantDeregister.setParticipantId(participantId);
+        participantDeregister.setParticipantType(participantType);
+
+        sender.sendParticipantDeregister(participantDeregister);
+    }
+
+    /**
+     * Handle a participantDeregister Ack message.
+     *
+     * @param participantDeregisterAckMsg the participantDeregisterAck message
      */
-    public boolean appliesTo(ParticipantMessage partipantMsg) {
-        return partipantMsg.appliesTo(participantType, participantId);
+    public void handleParticipantDeregisterAck(ParticipantDeregisterAck participantDeregisterAckMsg) {
+        LOGGER.debug("ParticipantDeregisterAck message received as responseTo {}",
+            participantDeregisterAckMsg.getResponseTo());
+    }
+
+    /**
+     * Handle a ParticipantUpdate message.
+     *
+     * @param participantUpdateMsg the ParticipantUpdate message
+     */
+    public void handleParticipantUpdate(ParticipantUpdate participantUpdateMsg) {
+        LOGGER.debug("ParticipantUpdate message received for participantId {}",
+            participantUpdateMsg.getParticipantId());
+
+        if (!participantUpdateMsg.appliesTo(participantType, participantId)) {
+            return;
+        }
+
+        Map<UUID, ControlLoopElementDefinition> clDefinitionMap =
+                participantUpdateMsg.getParticipantDefinitionUpdateMap().get(participantUpdateMsg.getParticipantId());
+
+        for (ControlLoopElementDefinition element : clDefinitionMap.values()) {
+            clElementDefsOnThisParticipant.put(element.getId(), element);
+        }
+
+        sendParticipantUpdateAck(participantUpdateMsg.getMessageId());
+    }
+
+    /**
+     * Method to send ParticipantUpdateAck message to controlloop runtime.
+     */
+    public void sendParticipantUpdateAck(UUID messageId) {
+        var participantUpdateAck = new ParticipantUpdateAck();
+        participantUpdateAck.setResponseTo(messageId);
+        participantUpdateAck.setMessage("Participant Update Ack message");
+        participantUpdateAck.setResult(true);
+
+        sender.sendParticipantUpdateAck(participantUpdateAck);
     }
 }