Copy values from a Child to another Child - Firebase Android Studio

 

private void confirmOrder() {

    FirebaseDatabase.getInstance().getReference().child("Hospital").child("Users").child(uid).child("Cart")
            .addListenerForSingleValueEvent(new ValueEventListener() {
                @Override
                public void onDataChange(@NonNull DataSnapshot snapshot) {

                    FirebaseDatabase.getInstance().getReference().child("Hospital").child("Users").child(uid).child("Order")
                            .setValue(snapshot.getValue()).addOnCompleteListener(new OnCompleteListener<Void>() {
                                @Override
                                public void onComplete(@NonNull Task<Void> task) {
                                    if(task.isSuccessful()){
                                        Toast.makeText(ProfileActivity.this, "Order Confirmed", Toast.LENGTH_SHORT).show();
                                    }else {
                                        Toast.makeText(ProfileActivity.this, "Failed!", Toast.LENGTH_SHORT).show();
                                    }
                                }
                            });
                }

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

                }
            });

}