Welcome to Java News and Code, where I tell you about interesting goings-on in the world of IT in general, and Java in particular.
And there’s always code.
On This Episode:
- Java Still on top in the Tiobe Index (but falling)
- Android O Final Preview
- Code Talkthrough: Android and the Cloud
Java Still on Top (but Falling)
According to the Tiobe index for August 2017, Java is at #1 and still has a commanding lead over all other languages. But its percentage score has fallen to about 13%, down from just over 19% a year ago.
And Java is not alone: the top 5 are all in decline from a year ago, with C at 6 1/2%, C++ at 5.6%, C# at 4.2%, and Python at 3.7%.
Scroll down on the page to see just how far ahead of the pack Java is:
From the graph you can see Java had a similar drop back in 2004 from which it rebounded strongly, so maybe this is a temporary trend. Who can say?
If you want to see how the index is put together, you can visit this page.
The Tiobe index is put together during the first week of each month.
So be sure to check that out.
Android O Final Preview is Out
On July 24th, Android O Developer Preview 4 was made available.
Preview 3 contained some very nice features like simplified settings, battery life optimizations, and per app notifications.
Preview 4 is the final preview before the official O release later this summer:
Preview 4 is a Release Candidate build of the Android O platform, and while it doesn’t have any new features, it contains the final system behaviors, bug fixes, and the final API (level 26).
Coming soon is also a new release of the Android Testing Support Library. The blog post says to stay tuned for more details coming soon.
And if you want to use Developer Preview 4, it’s recommended that you download Android Studio 3 Canary 1 as well, available in the Canary channel.
The show notes page has links to the blog post, download page, and lots more.
So be sure to check that out.
Code Talkthrough: Android and the Cloud
Finally, in today’s code talk through, I’d like to show you a recipe for building a RESTful web service application, deploying it to the Bluemix cloud as a Cloud Foundry application, and building an Android app to communicate with it.
To follow along with the video, you will need a Bluemix account, JDK 8, Eclipse, WebSphere Liberty, and Android studio installed on your computer.
You will need three projects from GitHub also:
- oDoTCore – the “guts” of the web services application
- OdotWrapper – the RESTful web services wrapper around oDoTCore
- AndroidCloudRecipe – the Android application code
In today’s show, I’m just going to show you the high level steps. The recipe walks you through it step-by-step if you’re interested in reproducing this yourself, which I hope you are.
Let’s get started.
First, clone the code from GitHub for the two web services projects.
git clone https://github.com/makotogo/oDoTCore
git clone https://github.com/makotogo/OdotWrapper
Now import the code into Eclipse.
With the code in Eclipse, build the oDoTCore JAR file using Maven, specifying the install goal so the JAR file gets installed to your local Maven repository.
Next, build the OdotWrapper WAR file using Maven, specifying the package goal.
Locate the WAR file in the target directory, and copy it to the WebSphere Liberty droppins directory.
Start WebSphere Liberty in Eclipse.
To verify the WebService is working, go to a browser and access this URL
When you see the JSON message, you know you have everything built and packaged correctly.
Now I’ll bundle the WebSphere Liberty server, including the WAR file, and deploy it to Bluemix.
For this part I need my Bluemix credentials, and the route I want to deploy it to.
I’m going over this fast, I know, but this is just an overview. The recipe has all the details.
Once I’ve deployed the application to Bluemix, I can test it and make sure it’s running. Open a browser, and hit this URL:
Again, when I see the JSON message “Hello from the server side!” I know it’s up and running.
Now to build the code for the Android app, run the app in the Android Emulator, and access the Web Service running in Bluemix.
Don’t worry, we’re almost there!
First, pull the code from GitHub:
Now import the code into Android Studio, and run the code in the Android Emulator. Choose the virtual device you setup when you installed and smoke tested Android Studio. It takes a minute or two for the device to start.
When the device starts, it will load the application. If you don’t see the application, click the Run button again in Android Studio.
Verify that the URL is correct (if not, change the code and run it again), and click the Info floating action button to invoke the Ping method. If you get back a Toast message that looks like this, then you’re good to go:
Under the hood, the Android app receives the JSON message we saw earlier in the browser, and is rendering it as a Toast message.
Now click on the Refresh From Server button, and the list should fill with data:
And that’s how you connect an Android app to an application running in the Cloud!
The developerWorks recipe has the steps broken down in much more detail, so be sure to check that out.
That’s all for this episode of Java News and Code.
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