android - Order by date in negative timestamp is not working in Firebase

Question

Query used:

q = FirebaseDatabase.getInstance().getReference().child("products").orderByChild("timestamp");
q.addValueEventListener(new ValueEventListener() {
    @Override
    public void onCancelled(DatabaseError databaseError) {
    }

    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {
        Log.d("datasnapshot", dataSnapshot.toString());

This value is in my Firebase database in same order.

Note: I am using negative value approach { -1 * new Date().getTime();} to store timestamp.

This value is in my Firebase database in same order:

Ke7K4vXyEt4gKnjf68H
timestamp: -1488345920790
Ke7KB2F1UKh8LoWcCY3
timestamp: -1488345945825
KeHlQIBnOE3diP8Wksh
timestamp: -1488521122407
KeI9nJtt4eg5Vd0rcAv
timestamp: -1488527774123
KeWwWW_ezG-cjmF8TNO
timestamp: -1488775680799
KeX7G0WOVidrMBbuGiT
timestamp: -1488778758960
Keg3mtNpyKStpVMMvRm
timestamp: -1488945623757
Keg4fN3rAN7uy5weFJz
timestamp: -1488945855094

Below order is what I get when I print the datasnapshot:

KeX7G0WOVidrMBbuGiT
timestamp: -1488778758960
Keg3mtNpyKStpVMMvRm
timestamp: -1488945623757
Keg4fN3rAN7uy5weFJz
timestamp: -1488945855094
Ke7K4vXyEt4gKnjf68H
timestamp: -1488345920790
KeWwWW_ezG-cjmF8TNO
timestamp: -1488775680799
KeHlQIBnOE3diP8Wksh
timestamp: -1488521122407
Ke7KB2F1UKh8LoWcCY3
timestamp: -1488345945825
KeI9nJtt4eg5Vd0rcAv
timestamp: -1488527774123

Answer 1

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