ref.updateChildren（）中的FirebaseException：路径X是更新中X / Y的祖先

Question

When trying to perform a multi-path write using path like " users/user " and " users/user/name " in the same ref.updatChildren() operation, app crashes with the following exception:

com.firebase.client.FirebaseException: Path X is an ancestor of X/Y in an update.

What is the best way to perform this kind of multi-path writes in Firebase? Thanks!

EDIT : In this particular case I wanted to achieve something like:

HashMap<String, Object> userUpdate = new HashMap<String, Object>();
HashMap<String, String> user = new HashMap<String, String>();
user.put("firstName", "Ivan");
user.put("initialOfLastName", "V");

userUpdate.put("/user", user);
userUpdate.put("/user/gender", "male")

ref.updateChildren(userUpdate);

Answer 1

Like the error states, you can't specify an update for /user and then specify a different update for /user/gender . Moving the gender update to the user map should work.

user.put("firstName", "Ivan");
user.put("initialOfLastName", "V");
user.put("gender", "male")

userUpdate.put("/user", user);

ref.updateChildren(userUpdate);

Answer 2

For cases like that, you'll have to use a nested HashMap at the top-level of the location you're updating.

HashMap<String,String> userUpdate = new HashMap<String,String>();
userUpdate.put("firstName", "Ivan");
userUpdate.put("initialOfLastName", "V");
ref.child(uid).updateChildren(userUpdate);