how to send push notification to the android device using GCM by java server?

Question

i am trying to send push notification to android device through java server. but when i deploy my server side code then i am getting following error. java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component.

package com.avilyne.gcm;

import java.io.IOException;

import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.google.android.gcm.server.Message;
import com.google.android.gcm.server.MulticastResult;
import com.google.android.gcm.server.Sender;

/**
 * Servlet implementation class GCMBroadcast
 */
@WebServlet("/GCMBroadcast")
public class GCMBroadcast extends HttpServlet {
    private static final long serialVersionUID = 1L;

    // The SENDER_ID here is the "Browser Key" that was generated when I
    // created the API keys for my Google APIs project.
    private static final String SENDER_ID = "AIzaSyD9GblH8c9qCBqDhLPKMca3dH8JsY4cgjg";

    // This is a *cheat*  It is a hard-coded registration ID from an Android device
    // that registered itself with GCM using the same project id shown above.
    private static final String ANDROID_DEVICE = "APA91bEtN2c3FYSFPpW-KuNtkWT6B9NJUviKN0L0DCjviJ2BtMyhZLqsFSFKfsySI1s88I0u68xETjvpqhvepffRSgwoTmpRXAv0Fbr0gH8CLhHO5CJC-M8";

    // This array will hold all the registration ids used to broadcast a message.
    // for this demo, it will only have the ANDROID_DEVICE id that was captured 
    // when we ran the Android client app through Eclipse.
    private List<String> androidTargets = new ArrayList<String>();

    /**
     * @see HttpServlet#HttpServlet()
     */
    public GCMBroadcast() {

        super();

        // we'll only add the hard-coded *cheat* target device registration id 
        // for this demo.
        androidTargets.add(ANDROID_DEVICE);

    }

    // This doPost() method is called from the form in our index.jsp file.
    // It will broadcast the passed "Message" value.
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        // We'll collect the "CollapseKey" and "Message" values from our JSP page
        String collapseKey = "";
        String userMessage = "";

        try {
            userMessage = request.getParameter("Message");
            collapseKey = request.getParameter("CollapseKey");
        } catch (Exception e) {
            e.printStackTrace();
            return;
        }

        // Instance of com.android.gcm.server.Sender, that does the
        // transmission of a Message to the Google Cloud Messaging service.
        Sender sender = new Sender(SENDER_ID);

        // This Message object will hold the data that is being transmitted
        // to the Android client devices.  For this demo, it is a simple text
        // string, but could certainly be a JSON object.
        Message message = new Message.Builder()

        // If multiple messages are sent using the same .collapseKey()
        // the android target device, if it was offline during earlier message
        // transmissions, will only receive the latest message for that key when
        // it goes back on-line.
        .collapseKey(collapseKey)
        .timeToLive(30)
        .delayWhileIdle(true)
        .addData("message", userMessage)
        .build();

        try {
            // use this for multicast messages.  The second parameter
            // of sender.send() will need to be an array of register ids.
            MulticastResult result = sender.send(message, androidTargets, 1);

            if (result.getResults() != null) {
                int canonicalRegId = result.getCanonicalIds();
                if (canonicalRegId != 0) {

                }
            } else {
                int error = result.getFailure();
                System.out.println("Broadcast failure: " + error);
            }

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

        // We'll pass the CollapseKey and Message values back to index.jsp, only so
        // we can display it in our form again.
        request.setAttribute("CollapseKey", collapseKey);
        request.setAttribute("Message", userMessage);

        request.getRequestDispatcher("index.jsp").forward(request, response);

    }

}

Could you give some more information on the error and where exactly the GCM Server is causing the exception? — Arthur Thompson
– Arthur Thompson, Commented Dec 16, 2015 at 16:22

Gaurav · Accepted Answer · 2015-12-16 13:52:13Z

try this code sample from google

send(String to,String msg){
try {
            // Prepare JSON containing the GCM message content. What to send and where to send.
            JSONObject jGcmData = new JSONObject();
            JSONObject jData = new JSONObject();
            jData.put("message", msg);

             jGcmData.put("to", to);

            // What to send in GCM message.
            jGcmData.put("data", jData);

            // Create connection to send GCM Message request.
            URL url = new URL("https://android.googleapis.com/gcm/send");
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestProperty("Authorization", "key=" + API_KEY);
            conn.setRequestProperty("Content-Type", "application/json");
            conn.setRequestMethod("POST");
            conn.setDoOutput(true);

            // Send GCM message content.
            OutputStream outputStream = conn.getOutputStream();
            outputStream.write(jGcmData.toString().getBytes());

            // Read GCM response.
            InputStream inputStream = conn.getInputStream();
            String resp = IOUtils.toString(inputStream);
            System.out.println(resp);
            System.out.println("Check your device/emulator for notification or logcat for " +
                    "confirmation of the receipt of the GCM message.");
        } catch (IOException e) {
            System.out.println("Unable to send GCM message.");
            System.out.println("Please ensure that API_KEY has been replaced by the server " +
                    "API key, and that the device's registration token is correct (if specified).");
            e.printStackTrace();
        }
}

Zp1k_e · Accepted Answer · 2016-05-19 16:44:45Z

1

i recommend use the google library: com.google.android.gcm.server you could have this:

Message message = new Message.Builder()
        .addData("title", "TITLE")
        .addData("message", "PUSH MESSAGE")
        .addData("action", "PUSH ACTION")
        .addData("content-available", "1")
        .build();

Sender sender = new Sender("PushApiKey");
MulticastResult result = sender.sendNoRetry(message, Arrays.asList("DEVICE-1", "DEVICE-n"));

On result you will have a response structure.

answered May 19, 2016 at 16:44

Zp1k_e

1382 silver badges9 bronze badges

2 Comments

paul Over a year ago

Where is this API documented?

paul Over a year ago

Thanks, but it appears that Google doesn't want us to use this. Their sample code for the project doesn't use it and I'm not able to access the notification part of Message even though its public in the code.

Collectives™ on Stack Overflow

how to send push notification to the android device using GCM by java server?

2 Answers 2

Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related