InsertReview.java

/**
     * Insert data review to collection of product
     * @param review
     */
    private void insertDataReview(ReviewModel review) {
        ReviewModel reviewModel = new ReviewModel(review.getName(), review.getReview(), review.getTimeStamp(), review.getTotalStarGiven());
        CollectionReference collectionReference = firebaseFirestore.collection("product");
        DocumentReference documentReference = collectionReference.document(productModelGlobal.getIdProduct());
        documentReference.collection("review")
                .add(reviewModel)
                .addOnSuccessListener(documentReference1 -> {
                    progressDialog.dismiss();
                    //after success, then update the rating in product
                    updateRating(review, productModelGlobal);
                })
                .addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        progressDialog.dismiss();
                        Toast.makeText(ReviewActivity.this, "Failed : " + e.getMessage(), Toast.LENGTH_SHORT).show();
                    }
                });
    }