Develop Reference

Sending APNS notifications with Java

I am currently developing Java web services that run on WebLogic on a server. There is a requirement that I need to send push notifications to mobile devices running on iOS. I do know what is required for developing GCM/FCM for sending notifications to Andriod devices. For iOS, I know there is APNS, but what Java library can I use to send the notifications?
Also, what are the required things (registration ID, etc) needed in order to send via APNS?
Any example codes?
I have googled and found out about java-apns and javapns, but I am not even sure if they are obsolete already.
Thanks in advance.

I can help you with what all are the things which are must to implement APNS. Please note that with the introduction of new HTTP/2.0 APNS API, a lot of things have changed which used to be before. (Good news is : Things have really become easy & simple now)
Would advise you to go through the below link:
https://developer.apple.com/library/ios/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/Chapters/Introduction.html
APNS Prerequisites:
1) APNS SSL Certificate, Key (Same for sandbox & production now, previously used to be different for production/development/voip etc. This is the most important step, as most of the issues related to APNS are due to the wrong certificate generation)
2) device token (specific to per iOS app running on an iOS device, your iOS client app needs to register with APNS to get this device token. Also device token is normally different for development & production environments. So please make sure your using the right token)
Once you have above mentioned certificate,key & device token for your iOS App, you can send APNS notifications from your application provider using APNS interface.
Please note that, device token can change anytime (normally during iOS software upgrade), so its always advisable to obtain fresh device token every time your app is launched.
On your query related to java library for apns, please note new APNS interface has a dependency on HTTP/2.0 . Both open source as well as enterprise versions (like AWS, Urban airship etc) are available which you can select based on your needs. Not sure if AWS supports new HTTP/2.0 interface. However its always advisable to use the latest APNS interface as per Apple guidelines.
Optionally, you can also use GCM as well to implement APNS.
https://developers.google.com/cloud-messaging/ios/start
However, your iOS app may need to register to GCM as well for the same. Basically the iOS device token will be mapped to GCM device token. However, you would still need to generate certificate,key as well as device token as I have mentioned.
I hope it answers your query.
_Ayush

Prevent phishing Android apps communicating with server

I have created and published on Google Play an Android app that communicates with my server. I want to check that my server (Java Servlet) only accepts requests from this Android app, so that if someone clones my code and creates a new app, when it tries to communicate with the server, the requests are rejected.
Is there a way to do that? Perhaps with domain names, or signed apps,...? This is to prevent phishing attacks.

You can get your app's signing key and check it on your server, but someone can get this information. If you use https for your connection, and use proguard, I think it's disincentive enough.

My app can't connect to another app service if service was installed after client app

my app connects to another app service and transfer some data. i configure permissions in manifest file and everything works fine. but i i have a big problem. my app works and connect properly to that service if only installed after that service! if i first install my app and then install that service, i doesn't work and i get this error:
Not allowed to bind to service Intent
even i restart my phone it doesn't effect! what is the problem here?

This is a known (by design/won't fix) issue with custom permissions - you cannot use a custom permission if it is not known to the system at the time when your app is installed.
Since the custom permission is defined in the manifest of the service apk which hasn't yet been installed, the system doesn't know about it when setting up the actual permissions of your client app, so it is effectively filtered out.
You will need to either get your users to install the service apk before the client, or else use some other scheme than a custom permission. For example, you might be able to do something by allowing any app to talk to you, but only responding to those with a key of some sort (though keys can be extracted by reverse engineering...)

Create a basic network app

I have a little question about an android app with a function "remote" use via internet.
So I have these ideas:
Create a webservice using php on the server, and refresh the client app all x time like 4-5 sec
Or make a java server (so I don't know how I can do that)
I just want make a remote connected via user/password to the server and the other app connect to the server and refresh his status.
Do you know the best way for do that?
Thanks

The question is not very precise, but as far as I understand it, both your ideas implement the 'pull' concept, that is the client app checking the status of the server every now and then.
If you want the app to be instantly notified of the server status change, I would suggest push notifications with GCM (Google Clound Messaging). You can find some basic descriptions and examples at: http://developer.android.com/google/gcm/index.html
Sending a server-to-client notification is simple regardless of the platform you use server side. E.g. for PHP integration with GCM, check out this thread: GCM with PHP (Google Cloud Messaging)

Android Bluetooth - Can't connect out

I am developing an application which uses Bluetooth to connect to a device and send/receive data. I am doing all of my testing with a Nexus One phone.
I have never been able to establish a SPP (serial port) connection from my phone to any device. However, I have been able to connect from a device (my laptop) to my phone using a Mac equivalent of PuTTY (The only exception to this is the "Bluetooth File Transfer" app from the Marketplace seems to work, but I don't think that uses RFCOM/SPP...).
I keep seeing this message in my LogCat logs:
ERROR/BluetoothService.cpp(78): stopDiscoveryNative: D-Bus error in StopDiscovery: org.bluez.Error.Failed (Invalid discovery session)
as well as these:
java.io.IOException: Operation Canceled
java.io.IOException: Software caused connection abort
I have tried using the UUID of "00001101-0000-1000-8000-00805F9B34FB" and I have also tried using the:
Method m = device.getClass().getMethod("createRfcommSocket", new Class[] { int.class });
sock = (BluetoothSocket) m.invoke(device, Integer.valueOf(1));
method instead of device.createRfcommSocketToServiceRecord(UUID); as well--with no luck.
I am using the BluetoothChat example and variations of that code to do all of my testing...
Solutions or suggestions would be great...or even a better/less complex example of some testing code I can run on the phone, or a python script or something I can run on my computer to help debug?
Thanks! I hope this isn't a bug with the Android OS, but if it is I hope to find a workaround.
EDIT: I should also note that most devices show up as "paired, but not connected" in the Bluetooth settings.
EDIT 2: The solution seems to be simply disabling any Bluetooth listening. See my answer post for more information.

The solution, as it turns out, was to disable the server functionality of the Bluetooth service. By only using createRfcommSocketToServiceRecord and never calling listenUsingRfcommWithServiceRecord (in the BluetoothChat example this means never starting the "AcceptThread") the problem was fixed.
Even though these two calls are supposed to be totally separated and have no affect on each other (according to the Android docs), simply commenting out listenUsingRfcommWithServiceRecord fixed my supposedly unrelated issue.
I can take the Bluetooth Chat program unedited and it will not be able to establish an outgoing connection to ANY bluetooth device I have tested (laptops, desktops, headsets, etc.), but if I remove that one thing it works flawlessly as a client.
Anyway, I hope this will help someone else if they come across the same issue. This must be a bug with the Android OS, or possibly the firmware on the Nexus One.

I would ignore the stopDiscovery error - its good that you're cancelling discovery before making your connection. Per the SDK docs:
Because discovery is a heavyweight
precedure for the Bluetooth adapter,
this method should always be called
before attempting to connect to a
remote device with connect().
Discovery is not managed by the
Activity, but is run as a system
service, so an application should
always call cancel discovery even if
it did not directly request a
discovery, just to be sure.
So with that said, were you able to get the Bluetooth Chat example to work before you made any modifications to the code?
The UUID you want for SPP/RFCOMM is:
static UUID UUID_RFCOMM_GENERIC = new UUID(0x0000110100001000L,0x800000805F9B34FBL);
or defined another way (both accomplish the same thing).
static final UUID UUID_RFCOMM_GENERIC = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");