Android : Delete A Folder at FirebaseStorage

Hello: i would like how to remove or delete a folder with it's content in FirebaseStorage?

i do have an admin app for admin to edit and delete items, i can delete items from FirebaseDatabase but can't delete FirebaseStorage.

Code to remove FirebaseRealTime:

productRef.addListenerForSingleValueEvent(new ValueEventListener() {
    @Override
    public void onDataChange(@NonNull DataSnapshot snapshot) {
        //If UID Existed Then would start Deleting
        if (snapshot.child(et_UID.getText().toString()).exists()) {
            DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    switch (which){
                        case DialogInterface.BUTTON_POSITIVE:
                            //Remove Image Folder / Product
                            productRef.child(et_UID.getText().toString()).removeValue();
                            productImagesRef.child(et_UID.getText().toString()).delete();
                            break;

                        case DialogInterface.BUTTON_NEGATIVE:
                            //No button clicked
                            break;
                    }
                }
            };
            AlertDialog.Builder builder = new AlertDialog.Builder(UpdateActivity.this);
            builder.setMessage("Are you sure?").setPositiveButton("Yes", dialogClickListener)
                    .setNegativeButton("No", dialogClickListener).show();
        } else {
            Toast.makeText(UpdateActivity.this, "UID Doesn't Exist.", Toast.LENGTH_SHORT).show();
        }
    }