@Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.act_groups);
        get_groups();
    }


void get_groups() {


    final String url =  "http://192.168.215.2:8000/get_user2";

    final StringRequest stringRequest = new StringRequest(Request.Method.POST, url,
            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {

                    Log.i("resp", response);

                }
            },

            new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {

                    Log.i("err", error.getMessage());

                }
            }
    ) {

        @Override
        protected Map<String, String> getParams() throws AuthFailureError {
            Map<String, String> map = new Hashtable<String, String>();
            map.put("name", Base64.encodeToString("".getBytes(), Base64.DEFAULT));
            return map;
        }
    };

    RequestQueue requestQueue = Volley.newRequestQueue(ActGroups.this);
    requestQueue.add(stringRequest);
}