Android推送通知

Question

I'm develop java rest api service and i need to make push notifications to android devices. I'm not really sure how to do it properly, my code is

public class FcmNotif {

    public final static String AUTH_KEY_FCM = "My key";
    public final static String API_URL_FCM = "https://fcm.googleapis.com/fcm/send";

// userDeviceIdKey is the device id you will query from your database
    public void pushFCMNotification(String userDeviceIdKey, String title, String message) throws Exception {

        String authKey = AUTH_KEY_FCM;   // You FCM AUTH key
        String FMCurl = API_URL_FCM;

        URL url = new URL(FMCurl);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();

        conn.setUseCaches(false);
        conn.setDoInput(true);
        conn.setDoOutput(true);

        conn.setRequestMethod("POST");
        conn.setRequestProperty("Authorization", "key=" + authKey);
        conn.setRequestProperty("Content-Type", "application/json");

        JsonObject json = new JsonObject();
        json.addProperty("to", userDeviceIdKey.trim());
        JsonObject info = new JsonObject();
        info.addProperty("title", title); // Notification title
        info.addProperty("body", message); // Notification body
        info.addProperty("image", "https://lh6.googleusercontent.com/-sYITU_cFMVg/AAAAAAAAAAI/AAAAAAAAABM/JmQNdKRPSBg/photo.jpg");
        info.addProperty("type", "message");
        json.add("data", info);
        System.out.println(json.toString());

        OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
        wr.write(json.toString());
        wr.flush();
        conn.getInputStream();
       // System.out.println(url.getH);
    }

    public static void main(String[] args) throws Exception {
        FcmNotif fcmN=new FcmNotif();
        fcmN.pushFCMNotification("user id ", "myFirstMessage", "hello");
        System.out.println("Done");
    }
}

AUTH_KEY_FCM i get from https://developers.google.com/mobile/add "Server API Key" and userDeviceIdKey its id that i get from running this code in android studio

String android_id = Settings.Secure.getString(getApplicationContext().getContentResolver(),
                Settings.Secure.ANDROID_ID);

Maybe i don't understand smth clearly, whan am i doing wrong? Response error

java.io.IOException: Server returned HTTP response code: 401 for URL: https://fcm.googleapis.com/fcm/send
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1840)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1441)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:254)
    at com.gmoika.FcmNotif.makeRequest(FcmNotif.java:88)
    at com.gmoika.FcmNotif.main(FcmNotif.java:111)

Answer 1

You can use Pushraven to send push notifications to android devices via fcm.

https://github.com/Raudius/Pushraven

Add the jar and do :

Pushraven.setKey(my_key);

Notification raven = new Notification();
raven.title("MyTitle")
  .text("Hello World!")
  .color("#ff0000")
  .to(client_key);

Pushraven.push(raven);

raven.clear();

For more detail documentation and jar file go to the link provided. The jar implements everything that needs to be done to send fcm push notifications.

Answer 2

Currently, you're only supposed to generate a valid Server Key by creating a Firebase Project, from there, go to Project Settings > Cloud Messaging tab. New Server API keys generated through the Google Dev Console is expected to not work for GCM/FCM, if it does, the behavior is not guaranteed -- you may receive a 401 error.

The value for userDeviceIdKey is supposed to be generated on the client side (usually) by calling getToken() . See Registration Token .