如何在android的Cloud Firestore中为JSON打补丁？

FirebaseFirestore db = FirebaseFirestore.getInstance();

DocumentReference docRef = db.collection("users").document("user1");

db.runTransaction(new Transaction.Function<Void>() {
    @Nullable
    @Override
    public Void apply(@NonNull Transaction transaction) throws FirebaseFirestoreException {
        DocumentSnapshot snapshot = transaction.get(docRef);
        if (snapshot.exists()) {
            // 获取当前文档的JSON数据
            Map<String, Object> data = snapshot.getData();

            // 对JSON数据进行修改
            data.put("key", "value");

            // 更新文档
            transaction.update(docRef, data);
        }
        return null;
    }
}).addOnSuccessListener(new OnSuccessListener<Void>() {
    @Override
    public void onSuccess(Void aVoid) {
        // 补丁应用成功
    }
}).addOnFailureListener(new OnFailureListener() {
    @Override
    public void onFailure(@NonNull Exception e) {
        // 补丁应用失败
    }
});