如何在Android/java中推送firestore Map类型数组中的新元素？

FirebaseFirestore db = FirebaseFirestore.getInstance();
DocumentReference docRef = db.collection("collectionName").document("documentId");

docRef.get().addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
    @Override
    public void onSuccess(DocumentSnapshot documentSnapshot) {
        if (documentSnapshot.exists()) {
            Map<String, Object> map = documentSnapshot.getData();
            // 处理当前的Map类型数组
        }
    }
});

map.put("newKey", "newValue");

docRef.set(map).addOnSuccessListener(new OnSuccessListener<Void>() {
    @Override
    public void onSuccess(Void aVoid) {
        // 更新成功
    }
}).addOnFailureListener(new OnFailureListener() {
    @Override
    public void onFailure(@NonNull Exception e) {
        // 更新失败
    }
});