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diff --git a/feature-pooling-messages/src/main/java/org/onap/policy/drools/pooling/state/State.java b/feature-pooling-messages/src/main/java/org/onap/policy/drools/pooling/state/State.java
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+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2018, 2020-2021 AT&T Intellectual Property. All rights reserved.
+ * Modifications Copyright (C) 2024 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.drools.pooling.state;
+
+import java.util.LinkedList;
+import java.util.List;
+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;
+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;
+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.
+ */
+public abstract class State {
+
+    private static final Logger logger = LoggerFactory.getLogger(State.class);
+
+    /**
+     * Host pool manager.
+     */
+    private final PoolingManager mgr;
+
+    /**
+     * Timers added by this state.
+     */
+    private final List<CancellableScheduledTask> timers = new LinkedList<>();
+
+    /**
+     * Constructor.
+     *
+     * @param mgr pooling manager
+     */
+    protected State(PoolingManager mgr) {
+        this.mgr = mgr;
+    }
+
+    /**
+     * Cancels the timers added by this state.
+     */
+    public final void cancelTimers() {
+        timers.forEach(CancellableScheduledTask::cancel);
+    }
+
+    /**
+     * Starts the state. The default method simply logs a message and returns.
+     */
+    public void start() {
+        logger.info("entered {} for topic {}", getClass().getSimpleName(), getTopic());
+    }
+
+    /**
+     * Transitions to the "start" state.
+     *
+     * @return the new state
+     */
+    public final State goStart() {
+        return mgr.goStart();
+    }
+
+    /**
+     * Transitions to the "query" state.
+     *
+     * @return the new state
+     */
+    public State goQuery() {
+        return mgr.goQuery();
+    }
+
+    /**
+     * 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
+     */
+    protected State goActive(BucketAssignments asgn) {
+        startDistributing(asgn);
+
+        if (asgn != null && asgn.hasAssignment(getHost())) {
+            return mgr.goActive();
+
+        } else {
+            return goInactive();
+        }
+    }
+
+    /**
+     * Transitions to the "inactive" state.
+     *
+     * @return the new state
+     */
+    protected State goInactive() {
+        return mgr.goInactive();
+    }
+
+    /**
+     * Processes a message. The default method just returns {@code null}.
+     *
+     * @param msg message to be processed
+     * @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;
+    }
+
+    /**
+     * Processes a message. The default method just returns {@code null}.
+     *
+     * @param msg message to be processed
+     * @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. 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;
+    }
+
+    /**
+     * Processes a message. The default method just returns {@code null}.
+     *
+     * @param msg message to be processed
+     * @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;
+    }
+
+    /**
+     * Processes a message. The default method just returns {@code null}.
+     *
+     * @param msg message to be processed
+     * @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;
+    }
+
+    /**
+     * 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) {
+            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 || source.equals(getHost())) {
+            logger.debug("ignore Leader message from {} for topic {}", msg.getSource(), getTopic());
+            return false;
+        }
+
+        // the new leader must equal the source
+        boolean result = source.equals(asgn.getLeader());
+
+        if (!result) {
+            logger.warn("Leader message from {} has an invalid assignment for topic {}", msg.getSource(), getTopic());
+        }
+
+        return result;
+    }
+
+    /**
+     * Publishes a message.
+     *
+     * @param msg message to be published
+     */
+    protected final void publish(Identification msg) {
+        mgr.publishAdmin(msg);
+    }
+
+    /**
+     * Publishes a message.
+     *
+     * @param msg message to be published
+     */
+    protected final void publish(Leader msg) {
+        mgr.publishAdmin(msg);
+    }
+
+    /**
+     * Publishes a message.
+     *
+     * @param msg message to be published
+     */
+    protected final void publish(Offline msg) {
+        mgr.publishAdmin(msg);
+    }
+
+    /**
+     * Publishes a message.
+     *
+     * @param msg message to be published
+     */
+    protected final void publish(Query msg) {
+        mgr.publishAdmin(msg);
+    }
+
+    /**
+     * Publishes a message on the specified channel.
+     *
+     * @param channel channel
+     * @param msg message to be published
+     */
+    protected final void publish(String channel, Heartbeat msg) {
+        mgr.publish(channel, msg);
+    }
+
+    /**
+     * Starts distributing messages using the specified bucket assignments.
+     *
+     * @param assignments assignments
+     */
+    protected final void startDistributing(BucketAssignments assignments) {
+        if (assignments != null) {
+            mgr.startDistributing(assignments);
+        }
+    }
+
+    /**
+     * Schedules a timer to fire after a delay.
+     *
+     * @param delayMs delay in ms
+     * @param task task
+     */
+    protected final void schedule(long delayMs, StateTimerTask task) {
+        timers.add(mgr.schedule(delayMs, task));
+    }
+
+    /**
+     * Schedules a timer to fire repeatedly.
+     *
+     * @param initialDelayMs initial delay ms
+     * @param delayMs delay ms
+     * @param task task
+     */
+    protected final void scheduleWithFixedDelay(long initialDelayMs, long delayMs, StateTimerTask task) {
+        timers.add(mgr.scheduleWithFixedDelay(initialDelayMs, delayMs, task));
+    }
+
+    /**
+     * Indicates that we failed to see our own heartbeat; must be a problem with the
+     * internal topic. Assumes the problem is temporary and continues to use the current
+     * bucket assignments.
+     *
+     * @return a new {@link StartState}
+     */
+    protected final State missedHeartbeat() {
+        publish(makeOffline());
+
+        return mgr.goStart();
+    }
+
+    /**
+     * Indicates that the internal topic failed; this should only be invoked from the
+     * StartState. Discards bucket assignments and begins processing everything locally.
+     *
+     * @return a new {@link InactiveState}
+     */
+    protected final State internalTopicFailed() {
+        publish(makeOffline());
+        mgr.startDistributing(null);
+
+        return mgr.goInactive();
+    }
+
+    /**
+     * Makes a heart beat message.
+     *
+     * @param timestampMs time, in milliseconds, associated with the message
+     *
+     * @return a new message
+     */
+    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 final Offline makeOffline() {
+        return new Offline(getHost());
+    }
+
+    /**
+     * Makes a query message.
+     *
+     * @return a new message
+     */
+    protected final Query makeQuery() {
+        return new Query(getHost());
+    }
+
+    public final BucketAssignments getAssignments() {
+        return mgr.getAssignments();
+    }
+
+    public final String getHost() {
+        return mgr.getHost();
+    }
+
+    public final String getTopic() {
+        return mgr.getTopic();
+    }
+
+    public final PoolingProperties getProperties() {
+        return mgr.getProperties();
+    }
+}