Send PUSH Notification to Android Client from java class on app-Engine - java

I have the requirement to send a PUSH notification to an android client from my java class. The class has been written using the guidelines provided at the url : http://www.vogella.de/articles/AndroidCloudToDeviceMessaging/article.html (Section 2.4 - Send Messages) This works fine on the standard application servers like JBOSS and Weblogic.
But the application needs to be moved to google app-engine but the class throws a compilation error saying : 'The class javax.net.ssl.HostnameVerifier is not supported by GAE's Java runtime environment'. Similar error is thrown for 'SSLSession' class too.
Is there a way this can be overcome ? Or is there is any other way to send PUSH notifications from Java classes running on the app-engine ?
Thanks,
Vinay

It can't be overcome directly, meaning you can't make those classes run on GAE. As for a solution, I'm not sure why you would want to use a custom HostnameVerifier, so just try without it: use HttpURLConnection instead of HttpsURLConnection and remove all the "hostnameVerifier" parts.
Edit: you can also use App Engine's fetch API, that is supported for sure.

Regarding your question Is there is any other way to send PUSH notifications from Java classes running on the app-engine?, the answer is yes, third party services such as Beaconpush or Spire.io could be integrated well with app engine, and in some cases could be much cheaper in terms of cost compared to using the App Engine Channel API.

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I am not sure if it’s possible or not a but I am trying to find out the way but not able to succeed as of now.
I found that we can parse AndroidManifest.xml of application to get the meta-data tag defining google play services lib but how to know about particular Service Api usage in that application.
I can think of about getting details in log cat of the application if play service produce the specific usage logs . But the problem is that that logs would be generated only at particular instance in the application and we may not aware of that instance.
Another approach I can think about if somehow we can parse network data using some android API or third-party API.
If you decompile source code and code is minified (secured), I think the only way is to try to "sniff" http traffic in/out from Android phone with for example Wireshark software

Embedded Web Service on Android device

I would like to program a WebService embedded on my android device (not the client part).
I've been evaluating Restlet Framework (Restlet) but i don't know if I go on the right way.
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Thank you so much!
Regards.
You should check whether Restlet is compliant with android,
not just from server side code, but also from client side code (respectively).
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An alternative approach would be to run a simple HTTP server on your device, for example the following nano http server I read about.
Another interesting project you should check is jetty for android which will hopefully give you support for servlet API as well.
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For example, look here
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How Connect to Remote MySQL server through Android App via JDBC

I first successfully connected via JDBC to a remote MySQL server with a Java program. That I understand how to do. My goal is do the same thing with an Android application and display data from a remote MySQL server.
Question 1 Can someone explain the process outline to do this via Android ? (I am new to Android and am a little stronger with Java, could use a little guidance).
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Not asking for it to be done for me. I just want someone to outline the main steps in order to make it happen. Just the process that needs to occur is all I am asking.
Question #1:
I stumbled upon this link some time ago:
http://docs.oracle.com/cd/E17076_02/html/installation/build_android_jdbc.html
(Disclaimer: I haven't read the whole tutorial myself)
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Your Question #2:
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You can use the same methods in Android you used in Java (Android is written in Java, after all, and you are able to use the majority of its libraries in android). However, be careful with doing so.
It would probably be better from a security standpoint to set up a web service to communicate with the database, rather than you allowing your android app to communicate directly with it, which would actually require you to embed your mysql username and password in the app code. A SOAP or RESTful web service could enable your server to communicate with the DB and then serve the data from it to your app.
It's done the same as in Java (Android apps are build in Java unless you're using the NDK).
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See this question.

Building java server which share interfaces wtih Android client

2 month ago i started to develop an android application which needs to call remote methods and receive complex objects (custom objects with custom feilds in it) from a server.
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We tried to use java RMI, but we faild because android doesn't support java RMI,
then we tried to use JAX-WS (with tomcat 7) and we also faild because JAXB can't handle intefaces. (-you can see more details here about jaxb issue-)
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Is it possible what we're trying to do? if not,
what other options avaible for us to call remote methods and receive complex objects from the server?
Thanks!
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Or you can write a kind of servlet programming to get the json request from the client, process it and send the json respoonse back to the client. If the application is data intensive, the JSON helps you a lot
Not sure if this is too late now (after 2 months of development), but there are frameworks that should make RPC easier for you (take care of linking both ends). Two I know of are Apache Thrift (definitely usable with Android - there are apps that use it) or Apache Etch (possibly).
Apache Thrift:
http://thrift.apache.org/
Apache Etch:
http://incubator.apache.org/etch/
Blog about Evernote choice of Thrift:
http://blog.evernote.com/tech/2011/05/26/evernote-and-thrift/
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Android Application communicating with GWT Application

I am developing a mobile application for Android. The application will act as a front-end for another GWT-application I have running on appspot.com. To communicate between the two, I need to send data from the client (Android Applcation) to the server (GWT-application), which must then be processed and data sent back to the client. What would be the best way to accomplish this? By "best" I mean simple enough for me to understand and implement, but also in line with good practice.
Any advice is greatly appreciated, as I am very new to GWT and can not find a lot of support on the internet.
Thanks!
I don't have much experience with Android application development but I guess with "sending data to the GWT application" you mean sending data to your App Engine backend/server.
In the end GWT is just compiled to plain Javascript and runs in the browser. So I don't see how you want to communicate with the GWT part of your app.
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Use RequestFactory (internally uses JSON) in your Android app (There is a special Requestfactory_client.jar package for that. See here for more details).

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