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diff --git a/catalog-dao/src/main/java/org/openecomp/sdc/be/dao/utils/CollectionUtils.java b/catalog-dao/src/main/java/org/openecomp/sdc/be/dao/utils/CollectionUtils.java
new file mode 100644
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+++ b/catalog-dao/src/main/java/org/openecomp/sdc/be/dao/utils/CollectionUtils.java
@@ -0,0 +1,125 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * 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.openecomp.sdc.be.dao.utils;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
+public final class CollectionUtils {
+	private CollectionUtils() {
+	}
+
+	/**
+	 * Add the content of the 'source' Set to the 'target' set and return the
+	 * union set.
+	 *
+	 * If 'source' is null then a new set is created and returned. If 'target'
+	 * is null then no content is added to the 'source' Set or newly created
+	 * set.
+	 *
+	 * @param source
+	 *            The Set to merge in the target Set.
+	 * @param target
+	 *            The Set in which the source set will be merged (through
+	 *            addAll).
+	 * @return The target Set with addition of source Set elements, or a new Set
+	 *         (including content of source set) if target was null.
+	 */
+	public static <T> Set<T> merge(Set<T> source, Set<T> target) {
+		Set<T> merged = new HashSet<T>();
+		if (target != null) {
+			merged.addAll(target);
+		}
+		if (source != null) {
+			merged.addAll(source);
+		}
+		return merged.isEmpty() ? null : merged;
+	}
+
+	/**
+	 * <p>
+	 * Add the content of the 'source' Map to the 'target' set and return the
+	 * union Map.
+	 * </p>
+	 * <p>
+	 * If 'source' is null then a new Map is created and returned. If 'target'
+	 * is null then no content is added to the 'source' Map or newly created
+	 * Map.
+	 * </p>
+	 *
+	 * @param source
+	 *            The Map to merge in the target Map.
+	 * @param target
+	 *            The Map in which the source Map will be merged (through
+	 *            addAll).
+	 * @param override
+	 *            If an key from the source map already exists in the target
+	 *            map, should it override (true) or not (false) the value.
+	 * @return The target Map with addition of source Map elements, or a new Map
+	 *         (including content of source set) if target was null.
+	 */
+	public static <T, V> Map<T, V> merge(Map<T, ? extends V> source, Map<T, V> target, boolean override) {
+		if (target == null) {
+			target = new HashMap();
+		}
+
+		if (source != null) {
+			for (Entry<T, ? extends V> entry : source.entrySet()) {
+				if (override || !target.containsKey(entry.getKey())) {
+					target.put(entry.getKey(), entry.getValue());
+				}
+			}
+		}
+		return target.isEmpty() ? null : target;
+	}
+
+	/**
+	 * Merge two lists, the merge is performed based on the contains method so
+	 * elements presents both in source and target are not added twice to the
+	 * list.
+	 *
+	 * @param source
+	 *            The source list.
+	 * @param target
+	 *            The target list.
+	 * @return A list that represents the merged collections.
+	 */
+	public static <T> List<T> merge(List<T> source, List<T> target) {
+		List<T> merged = target == null ? new ArrayList<T>() : target;
+
+		if (source == null) {
+			return merged;
+		}
+
+		for (T t : source) {
+			if (!merged.contains(t)) {
+				merged.add(t);
+			}
+		}
+
+		return merged;
+	}
+}