Fix the null pointer for operation json list.

modules/charon-core/src/main/java/org/wso2/charon3/core/encoder/JSONDecoder.java

@@ -746,13 +746,26 @@ private ComplexAttribute buildComplexValue(AttributeSchema attributeSchema,
  */
  public ArrayList<PatchOperation> decodeRequest(String scimResourceString) throws BadRequestException {
 
-
  ArrayList<PatchOperation> operationList = new ArrayList<PatchOperation>();
  try {
  //decode the string into json representation
  JSONObject decodedJsonObj = new JSONObject(new JSONTokener(scimResourceString));
  //obtain the Operations values
  JSONArray operationJsonList = (JSONArray) decodedJsonObj.opt(SCIMConstants.OperationalConstants.OPERATIONS);
+
+ //check if operationJsonList is null
+ if (operationJsonList == null) {
+
+ //throw appropriate exception based on the key check
+ if (decodedJsonObj.has(StringUtils.lowerCase(SCIMConstants.OperationalConstants.OPERATIONS))) {
+ throw new BadRequestException("Invalid JSON schema.", ResponseCodeConstants.INVALID_SYNTAX);
+ }
+
+ //if the key with lowercase name does not exist, throw this exception
+ throw new BadRequestException(ResponseCodeConstants.INVALID_SYNTAX);
+ }
+
+
  //for each operation, create a PatchOperation object and add the relevant values to it
  for (int count = 0; count < operationJsonList.length(); count++) {
  JSONObject operation = (JSONObject) operationJsonList.get(count);