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diff --git a/utils/src/main/java/org/onap/policy/common/utils/services/OrderedServiceImpl.java b/utils/src/main/java/org/onap/policy/common/utils/services/OrderedServiceImpl.java
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+++ b/utils/src/main/java/org/onap/policy/common/utils/services/OrderedServiceImpl.java
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+/*
+ * ============LICENSE_START=======================================================
+ * utils
+ * ================================================================================
+ * Copyright (C) 2019 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.common.utils.services;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.ServiceLoader;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This class is a template for building a sorted list of service instances,
+ * which are discovered and created using 'ServiceLoader'. 
+ */
+public class OrderedServiceImpl<T extends OrderedService> {
+    // logger
+    private static Logger  logger = LoggerFactory.getLogger(OrderedServiceImpl.class); 
+
+    // sorted list of instances implementing the service
+    private List<T> implementers = null;
+
+    // 'ServiceLoader' that is used to discover and create the services
+    private ServiceLoader<T> serviceLoader = null;
+
+    // use this to ensure that we only use one unique instance of each class
+    @SuppressWarnings("rawtypes")
+    private static HashMap<Class,OrderedService> classToSingleton = new HashMap<>();
+
+    /**
+     * Constructor - create the 'ServiceLoader' instance.
+     *
+     * @param clazz the class object associated with 'T' (I supposed it could
+     *     be a subclass, but I'm not sure this is useful)
+     */
+    public OrderedServiceImpl(Class<T> clazz) {
+        // This constructor wouldn't be needed if 'T.class' was legal
+        serviceLoader = ServiceLoader.load(clazz);
+    }
+
+    /**
+     * Get List of implementers.
+     * 
+     * @return the sorted list of services implementing interface 'T' discovered
+     *     by 'ServiceLoader'.
+     */
+    public synchronized List<T> getList() {
+        if (implementers == null) {
+            rebuildList();
+        }
+        return implementers;
+    }
+
+    /**
+     * This method is called by 'getList', but could also be called directly if
+     * we were running with a 'ClassLoader' that supported the dynamic addition
+     * of JAR files. In this case, it could be invoked in order to discover any
+     * new services implementing interface 'T'. This is probably a relatively
+     * expensive operation in terms of CPU and elapsed time, so it is best if it
+     * isn't invoked too frequently.
+     *
+     * @return the sorted list of services implementing interface 'T' discovered
+     *      by 'ServiceLoader'.
+     */
+    @SuppressWarnings("unchecked")
+    public synchronized List<T> rebuildList() {
+        // build a list of all of the current implementors
+        List<T> tmp = new LinkedList<>();
+        for (T service : serviceLoader) {
+            tmp.add((T)getSingleton(service));
+        }
+
+        // Sort the list according to sequence number, and then alphabetically
+        // according to full class name.
+        Collections.sort(tmp, (o1, o2) -> {
+            int s1 = o1.getSequenceNumber();
+            int s2 = o2.getSequenceNumber();
+            if (s1 < s2) {
+                return -1;
+            } else if (s1 > s2) {
+                return 1;
+            } else {
+                return o1.getClass().getName().compareTo(o2.getClass().getName());
+            }
+        });
+
+        // create an unmodifiable version of this list
+        implementers = Collections.unmodifiableList(tmp);
+        logger.info("***** OrderedServiceImpl implementers:\n {}", implementers);
+        return implementers;
+    }
+
+    /**
+     * If a service implements multiple APIs managed by 'ServiceLoader', a
+     * separate instance is created for each API. This method ensures that
+     * the first instance is used in all of the lists.
+     *
+     * @param service this is the object created by ServiceLoader
+     * @return the object to use in place of 'service'. If 'service' is the first
+     *     object of this class created by ServiceLoader, it is returned. If not,
+     *     the object of this class that was initially created is returned
+     *     instead.
+     */
+    private static synchronized OrderedService getSingleton(OrderedService service) {
+        // see if we already have an instance of this class
+        OrderedService rval = classToSingleton.get(service.getClass());
+        if (rval == null) {
+            // No previous instance of this class exists -- use the supplied
+            // instance, and place it in the table.
+            rval = service;
+            classToSingleton.put(service.getClass(), service);
+        }
+        return rval;
+    }
+}