diff --git a/packages/amplify-appsync-simulator/src/velocity/value-mapper/map.ts b/packages/amplify-appsync-simulator/src/velocity/value-mapper/map.ts
index 2362e72d8ad..cd7ebe778b7 100644
--- a/packages/amplify-appsync-simulator/src/velocity/value-mapper/map.ts
+++ b/packages/amplify-appsync-simulator/src/velocity/value-mapper/map.ts
@@ -3,67 +3,67 @@ import { JavaInteger } from './integer';
 import { toJSON } from './to-json';
 
 export class JavaMap {
-  private map: Map<string, any>;
+  private __map: Map<string, any>;
   // eslint-disable-next-line @typescript-eslint/ban-types
-  private mapper: Function;
+  private __mapper: Function;
   constructor(obj, mapper) {
-    this.mapper = mapper;
-    this.map = new Map();
+    this.__mapper = mapper;
+    this.__map = new Map();
     Object.entries(obj).forEach(([key, value]) => {
-      this.map.set(key, value);
+      this.__map.set(key, value);
     });
   }
 
   clear() {
-    this.map.clear();
+    this.__map.clear();
   }
 
   containsKey(key) {
-    return this.map.has(key);
+    return this.__map.has(key);
   }
 
   containsValue(value) {
-    return Array.from(this.map.values()).indexOf(value) !== -1;
+    return Array.from(this.__map.values()).indexOf(value) !== -1;
   }
 
   entrySet() {
-    const entries = Array.from(this.map.entries()).map(([key, value]) =>
+    const entries = Array.from(this.__map.entries()).map(([key, value]) =>
       createMapProxy(
         new JavaMap(
           {
             key,
             value,
           },
-          this.mapper,
+          this.__mapper,
         ),
       ),
     );
 
-    return new JavaArray(entries, this.mapper);
+    return new JavaArray(entries, this.__mapper);
   }
 
   equals(value) {
-    return Array.from(this.map.entries()).every(([key, v]) => value.get(key) === v);
+    return Array.from(this.__map.entries()).every(([key, v]) => value.get(key) === v);
   }
 
   get(key) {
-    if (this.map.has(key.toString())) {
-      return this.map.get(key.toString());
+    if (this.__map.has(key.toString())) {
+      return this.__map.get(key.toString());
     }
     return null;
   }
 
   isEmpty() {
-    return this.map.size === 0;
+    return this.__map.size === 0;
   }
 
   keySet() {
-    return new JavaArray(Array.from(this.map.keys()).map(this.mapper as any), this.mapper);
+    return new JavaArray(Array.from(this.__map.keys()).map(this.__mapper as any), this.__mapper);
   }
 
   put(key, value) {
-    const saveValue = this.mapper(value);
-    this.map.set(key, saveValue);
+    const saveValue = this.__mapper(value);
+    this.__map.set(key, saveValue);
     return saveValue;
   }
 
@@ -75,24 +75,24 @@ export class JavaMap {
   }
 
   remove(key) {
-    if (!this.map.has(key)) {
+    if (!this.__map.has(key)) {
       return null;
     }
-    const value = this.map.get(key);
-    this.map.delete(key);
+    const value = this.__map.get(key);
+    this.__map.delete(key);
     return value;
   }
 
   size() {
-    return new JavaInteger(this.map.size);
+    return new JavaInteger(this.__map.size);
   }
 
   values() {
-    return new JavaArray(Array.from(this.map.values()), this.mapper);
+    return new JavaArray(Array.from(this.__map.values()), this.__mapper);
   }
 
   toJSON() {
-    return Array.from(this.map.entries()).reduce(
+    return Array.from(this.__map.entries()).reduce(
       (sum, [key, value]) => ({
         ...sum,
         [key]: toJSON(value),
@@ -105,14 +105,14 @@ export class JavaMap {
 export function createMapProxy(map) {
   return new Proxy(map, {
     get(obj, prop) {
-      if (map.map.has(prop)) {
+      if (map.__map.has(prop)) {
         return map.get(prop);
       }
       return map[prop];
     },
     set(obj, prop, val) {
       if (typeof val !== 'function') {
-        map.map.set(prop, val);
+        map.__map.set(prop, val);
       }
       return true;
     },