Use Apple Push Notification Service through Java

Question

Am trying to implement a Java program which sends an Apple Push Notification to an iPhone client app... Found the following library: Java APNs

Provider code:

Created the following code (from Javapns) to use in my app:

try {
    PayLoad payLoad = new PayLoad();

    payLoad.addAlert("My alert message");
    payLoad.addBadge(45);
    payLoad.addSound("default");

    PushNotificationManager pushManager = PushNotificationManager.getInstance();
    pushManager.addDevice("iPhone", "f4201f5d8278fe39545349d0868a24a3b60ed732");
    log.warn("Initializing connectiong with APNS...");

    // Connect to APNs
    pushManager.initializeConnection(HOST, PORT, 
                                 "/etc/Certificates.p12", "password", 
    SSLConnectionHelper.KEYSTORE_TYPE_PKCS12);

    Device client = pushManager.getDevice("Lambo");

    // Send Push
    log.warn("Sending push notification...");
    PushNotificationManager.getInstance().sendNotification(client, payLoad);
 }
 catch (Exception e) {
    throw new ApnsPushNotificationException("Unable to send push " + e);
 }

When I run this app (as you can see through the Log4j statements) there's no exceptions which occur:

  WARN  [MyCode] Initializing connectiong with APNS...
  WARN  [MyCode] Sending push notification...

But my client app doesn't receive any notifications!

IDPP Registration Process:

Also, did the following on the iPhone Developer Program Portal (IDPP):

• Created the APNS based SSL Certificate and Keys

• Created and installed the provisioning profile

• Installed the SSL Certificate and Key on the server.

Have read over the Apple Push Notification Service Guide several times and noticed a few things:

(1) On page 15, it states that the device token is not the same as the device UDID (which I am currently incorrectly passing in as the second parameter inside the PushNotificationManager.addDevice() method (see above)).

On page 17, it states:

"APNs generates a device token using information contained in the unique device certificate. The device token contains an identifier of the device. It then encrypts the device token with a token key and returns it to the device. The device returns the device token to the requesting application as an NSData object. The application then must deliver the device token to its provider in either binary or hexidecimal format."

iPhone OS Client Implementation

(2) After reading pages 33 - 34, I discovered that I didn't include the Objective-C code to have the app register with APNs.

Am not an Objective-C developer, so is this where I can recover the device code or do I have to get it from the certificate?

Where do I obtain the device token (sorry, someone else wrote the Objective-C client app and I am a Java Developer)?

Question(s):

(1) With the exception of not knowing where to get the device token and the mobile client code registration, is there anything else that I have not looked over or missed?

(2) Am I using the Javapns library the right way?

Thank you for taking the time to read this...

Answer 1

Just a little tip, in order to convert your received token into a format suitable for registration with javapns, this code will do the trick:

- (NSString *)convertTokenToDeviceID:(NSData *)token {
NSMutableString *deviceID = [NSMutableString string];

// iterate through the bytes and convert to hex
unsigned char *ptr = (unsigned char *)[token bytes];

for (NSInteger i=0; i < 32; ++i) {
    [deviceID appendString:[NSString stringWithFormat:@"%02x", ptr[i]]];
}

return deviceID;

}

Answer 2

As a shameful self-advertising, I encourage to use java-apns library. Your code will look like:

ApnsService service =
     APNS.newService()
     .withCert("/etc/Certificates.p12", "password")
     .withSandboxDestination() // or .withProductionDestination()
     .build();

String payload =
    APNS.newPayload()
    .alertBody("My alert message")
    .badge(45)
    .sound("default")
    .build();

String deviceToken = "f4201f5d8278fe39545349d0868a24a3b60ed732";

log.warn("Sending push notification...");
service.push(deviceToken, payload);

Answer 3

1. Your Java code looks solid! However, don't forget to close the connection, through PushNotificationManager.closeConnection(). It's important to cleanup after yourself.

   As a side comment, I notice that you are adding the device 'iPhone' but querying for 'Lambo' afterwards. This is an indication of a bug.

2. The device token shown in the code is incorrect. Device tokens, currently, as 32-bit long value, which gets hexed into 64 characters. I assume that the server is failing silently when pushing the notification to invalid token!

3. The only way to get the device token is from the app itself. As provided by the Push Notification guide suggests, the iPhone app needs to register for notification upon launch. In the application:didRegisterForRemoteNotificationsWithDeviceToken:, the iPhone needs to send the device token to your java provider server. (For debugging purposes, you can just NSLog the device token and use it; it never changes across runs).

   I would recommend that you create a server in your java provider server to receive device tokens. Set up a ServerSocket to receive connections from the iPhone and their device token (and any additional info you need) and insert the tokens in the database.

Answer 4

I tried this and I keep getting hanged when sending the notification, and nothing gets sent.

The issue stems from the following function:

         public void sendNotification(Device device, PayLoad payload) 

It seems that the bufferedreader has NULL

           BufferedReader in = 
           new BufferedReader(new InputStreamReader(this.socket.getInputStream() ) );

So when this portion of the code gets hit it just hangs there in endless loop

  logger.debug( "In: [" + in.readLine() + "]" );

This output is [null]

So then right after then the loops get executed:

      while ( ! this.socket.isInputShutdown() ) {
          while( in.ready() ) {
              logger.debug("ready now");
              logger.debug(in.readLine());
              System.out.println( this.socket.getInputStream().read() );
          }
      }

The code enters the first while loop and waits for the BufferedReader in to be ready and just keeps waiting..... ad that is your hanging

Answer 5

JavaPNS was recently updated to 2.0, and fixed ALL reported issues up to the release date. It does fix the issue you are describing, and using the library is MUCH simpler than it ever was (you can push a notification with a single line of code now).

Answer 6

You seem to be missing the token

pushManager.addDevice("iPhone", "f4201f5d8278fe39545349d0868a24a3b60ed732");

Takes id and token check:

https://github.com/o-sam-o/javapns/blob/master/src/javapns/notification/PushNotificationManager.java#L501

The only way to get a token is from the iphone app. A valid token looks something like this: 1d2d6f34 c5028bca c50df5f9 1992c912 ce7deae8 3bbe7da5 447f6a68 cfecdc0e