How To Compare My Contact With The Contacts Uploaded In Firebase Database

Firstly I would like to show you my Firebase database tree -Users | ----959670000 | | | ------name | + ----750890000 +------859200000 I had a root n

Solution 1:

public boolean getAllUserList(final ArrayList<ContactPojo> contactList){//all contact list as an argument
        databaseReference();
        for (int i = 0; i < contactList.size(); i++) {
            checkingMatchedData(contactList.get(i).getPhone(),contactList.get(i));
        }
        return false;
    }

public void checkingMatchedData(String phone, final ContactPojo contPojo){
    Query query=reference.orderByChild("phone").equalTo(Long.parseLong(phone));
    ValueEventListener listener=new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
            if (dataSnapshot.getValue()!=null) {
                for (DataSnapshot snapshot : dataSnapshot.getChildren()) {
                    UserPojo pojo = snapshot.getValue(UserPojo.class);
                    ContactPojo contactPojo = new ContactPojo();
                    contactPojo.setName(pojo.getName());
                    contactPojo.setPhone(String.valueOf(pojo.getPhone()));
                    contactPojo.setPhoto_uri(pojo.getImageUrl());
                    contactPojo.setUserId(pojo.getUserId());
                    contactPojo.setTypeOfData(101);//this is used to define type of user i.e 101 for registered user or 100 for unregistered
                    finalUserList.add(contactPojo);
                }
            }else {
                contPojo.setTypeOfData(100);
                finalUserList.add(contPojo);
            }
        }

        @Override
        public void onCancelled(@NonNull DatabaseError databaseError) {

        }
    };
    query.addListenerForSingleValueEvent(listener);
}
public void databaseReference(){
    reference= FirebaseDatabase.getInstance().getReference().child("Users");
}