How to store data in realtime database properly under user authenticated key?

Question

I have stored some data in realtime database under autenticated key using shared preferences. I used SharedPreferences because I used multiple pages for getting

Answer 1

Moved the answer to this post because second one was closed as a duplicate -

In order to get what you're looking for you'll need to iterate on the list of details you have and set one at a time as a value under your user's UID OR just create an object with all of the params you need and send the object.

Example with HashMap to iterate :

HashMap hashMap = new HashMap();

SharedPreferences sp = getSharedPreferences("Mypref", 0);
hashMap.put("first_name", sp.getString("first_name", null))
hashMap.put("last_name", sp.getString("last_name",null))
hashMap.put("fathers_name", sp.getString("fathers_name", null))
hashMap.put("date", sp.getString("date", null))
hashMap.put("income", sp.getString("income", null))
(.......)

Iterator iterator = hashMap.entrySet().iterator() 
if (hashMap.hasNext()) {
    iterator.next() 
    reference.child("User").child(Objects.requireNonNull(mAuth.getUid())).child(iterator.getKey).setValue(iterator.getValue);
}