RefReceiver.java

public class RefReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        String encodedInstallReferrer = intent.getStringExtra("referrer");

        String installReferrer = "";

        if (encodedInstallReferrer != null) {
            try {
                installReferrer = URLDecoder.decode(encodedInstallReferrer, "utf-8");
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
        }

        Log.d("GrowthLink", installReferrer);
        String clickId = null;
        for (String param : installReferrer.split("&")) {
            String pair[] = param.split("=");
            String key = pair[0];
            String value = "";
            if (pair.length > 1) {
                value = pair[1];
            }
            if (key.equals("growthlink.clickId")) {
                clickId = value;
            }
            //androidReferrerパラメータを取得できます(key,value)
        }
        //オープン数,インストール数の反映をしたい場合
        if (clickId != null) {
            final String linkClickId = clickId;
            new AsyncTask<Void, Void, String>() {
                @Override
                protected String doInBackground(Void... params) {
                    String result = null;
                    RequestBody requestBody = new FormEncodingBuilder()
                            .add("applicationId", "{Application ID}")
                            .add("clickId", linkClickId)
                            .add("install", "true")
                            .add("credentialId", "{Credentia Key}")
                            .build();
                    Request request = new Request.Builder()
                            .url("https://api.link.growthbeat.com/1/click/consume")
                            .post(requestBody)
                            .build();
                    OkHttpClient client = new OkHttpClient();
                    try {
                        Response response = client.newCall(request).execute();
                        result = response.body().string();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                    return result;
                }

                @Override
                protected void onPostExecute(String result) {
                    Log.d("GrowthLink", result);
                }
            }.execute();
        }
    }

}