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diff --git a/src/main/java/org/onap/pnfsimulator/template/search/JsonUtils.java b/src/main/java/org/onap/pnfsimulator/template/search/JsonUtils.java
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+/*-
+ * ============LICENSE_START=======================================================
+ * Simulator
+ * ================================================================================
+ * Copyright (C) 2019 Nokia. 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.pnfsimulator.template.search;
+
+import com.google.common.base.Strings;
+import com.google.gson.Gson;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonPrimitive;
+import org.bson.Document;
+
+/**
+ * This util flattens nested json and produces json with keys transformed to form of json path
+ * where default separator between parent object key and object key is ':'
+ * For easing searching of boolean values, they are converted to its string representation
+ */
+public class JsonUtils {
+
+    private static final String DEFAULT_PARENT_KEY_TO_OBJECT_KEY_SEPARATOR = ":";
+    private static final String SEED_PREFIX = "";
+    private static final Gson GSON = new Gson();
+
+    public JsonObject flatten(JsonObject original) {
+        return flattenWithPrefixedKeys(DEFAULT_PARENT_KEY_TO_OBJECT_KEY_SEPARATOR, original.deepCopy(), SEED_PREFIX, new JsonObject());
+    }
+
+    public JsonObject flatten(String parentKeyToKeySeparator, JsonObject original) {
+        return flattenWithPrefixedKeys(parentKeyToKeySeparator, original.deepCopy(), SEED_PREFIX, new JsonObject());
+    }
+
+    public Document flatten(Document original) {
+        return flatten(DEFAULT_PARENT_KEY_TO_OBJECT_KEY_SEPARATOR, original);
+    }
+
+    public Document flatten(String parentKeyToKeySeparator, Document original) {
+        JsonObject originalJsonObject = GSON.fromJson(original.toJson(), JsonObject.class);
+        JsonObject flattenedJson = flatten(parentKeyToKeySeparator, originalJsonObject);
+        return Document.parse(flattenedJson.toString());
+    }
+
+    private JsonObject flattenWithPrefixedKeys(String parentKeyToKeySeparator, JsonElement topLevelElem, String prefix, JsonObject acc) {
+        if (topLevelElem.isJsonPrimitive()) {
+            handleJsonPrimitive(topLevelElem, prefix, acc);
+        } else if (topLevelElem.isJsonArray()) {
+            handleJsonArray(parentKeyToKeySeparator, topLevelElem, prefix, acc);
+        } else if (topLevelElem.isJsonObject()) {
+            handleJsonObject(parentKeyToKeySeparator, topLevelElem, prefix, acc);
+        } else {
+            acc.add(prefix, topLevelElem.getAsJsonNull());
+        }
+        return acc.deepCopy();
+    }
+
+    private void handleJsonObject(String parentKeyToKeySeparator, JsonElement topLevelElem, String prefix, JsonObject acc) {
+        boolean isEmpty = true;
+        JsonObject thisToplevelObj = topLevelElem.getAsJsonObject();
+        for (String key : thisToplevelObj.keySet()) {
+            isEmpty = false;
+            String keyPrefix = String.format("%s%s%s", prefix, parentKeyToKeySeparator, key);
+            flattenWithPrefixedKeys(parentKeyToKeySeparator, thisToplevelObj.get(key), keyPrefix, acc);
+        }
+        if (isEmpty && !Strings.isNullOrEmpty(prefix)) {
+            acc.add(prefix, new JsonObject());
+        }
+    }
+
+    private void handleJsonArray(String parentKeyToKeySeparator, JsonElement topLevelElem, String prefix, JsonObject acc) {
+        JsonArray asJsonArray = topLevelElem.getAsJsonArray();
+        if (asJsonArray.size() == 0) {
+            acc.add(prefix, new JsonArray());
+        }
+        for (int i = 0; i < asJsonArray.size(); i++) {
+            flattenWithPrefixedKeys(parentKeyToKeySeparator, asJsonArray.get(i), String.format("%s[%s]", prefix, i), acc);
+        }
+    }
+
+    private void handleJsonPrimitive(JsonElement topLevelElem, String prefix, JsonObject acc) {
+        JsonPrimitive jsonPrimitive = topLevelElem.getAsJsonPrimitive();
+        if (jsonPrimitive.isBoolean()) {
+            acc.add(prefix, new JsonPrimitive(jsonPrimitive.getAsString()));
+        } else {
+            acc.add(prefix, topLevelElem.getAsJsonPrimitive());
+        }
+    }
+}