volleyを使って検索機能を実装したい

public class MainActivity extends AppCompatActivity {

    private RequestQueue queue;

    String word;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final EditText editText = (EditText)findViewById(R.id.edit);
        editText.setOnKeyListener(new OnKeyListener() {
            @Override
            public boolean onKey(View view, int i, KeyEvent keyEvent) {
                if (editText == null){
                    //文字入力の催促

                }else if (keyEvent.getAction() == KeyEvent.ACTION_DOWN
                        && i == KeyEvent.KEYCODE_ENTER) {
                    queue = Volley.newRequestQueue(getApplicationContext());
                    requestVolley();
                    return true;
                }
                return false;
            }
        });

    }

    private void requestVolley() {

        try {
            JSONObject jsonObject = new JSONObject();
            jsonObject.put("",word); //nullのまま

            String url = "http://api.androidhive.info/volley/person_object.json";
            queue.add(new JsonObjectRequest(Request.Method.GET, url, jsonObject,
                    new Response.Listener<JSONObject>() {
                        @Override
                        public void onResponse(JSONObject response) {
                            try {
                                String name = (response.getString("name"));
                                String email = (response.getString("email"));

                                Intent intent = new Intent(MainActivity.this, ResultActivity.class);
                                intent.putExtra("name", name);
                                intent.putExtra("email", email);
                                startActivity(intent);

                            }catch (JSONException e) {
                                e.printStackTrace();
                            }
                        }
                    }, null));
            queue.start();

        }catch (JSONException e){
            e.printStackTrace();
        }
    }
}