Wrapping Up
We have reached the end of our tour of programming. While this book has covered a good number of different topics, this is only a basic introduction to programming, which is but a stepping-stone into the field of Computer Science. The goal of this book was to lay a foundation that you can build on going forward. Now it is your job to continue the construction process.
36.1 What You Have Learned
The early parts of this book focused primarily on basic constructs used to tell a computer how to do things. You learned the use of conditional logic and looping constructs that could be put around simple sequential commands to express actions that you wanted to have the machine carry out. You learned how to break problems into pieces. At first the approach was to build separate functions that handled one part of the problem at a time, and ways of grouping data that made sense. Later on you saw that problems can be decomposed into objects that combine data with functionality. This learning to break problems apart should have had an impact on how you looked at many things through your life and in your studies outside of Computer Science.
A further step in how you approached problems came in the form of thinking about abstractions. It was possible to write a solution to one problem, but so much more could be gained if you tune that solution so that parts of it can be made to work in many different problems. The desire to abstract code appeared in many different contexts through the book with abstractions that varied over types, functionality, or both.
The modern world is teaming with data. Data is produced by all types of devices during all types of activities. You have learned how to give instructions to a computer to make it process data for you. There are limits on how much you can do by hand, but a computer can read and process millions or even billions of values quickly. You now know how to pull this data from files or over networks. You can deal with data in flat text, XML, or binary. You can use higher-order constructs to do the processing and apply multithreading to speed it up.
The also have the ability to write programs that display Graphical User Interfaces (GUIs) and draw custom graphics. You can write programs that talk to one another over networked sockets. When it really comes down to it, you have learned the basic tools to make a computer do pretty much anything. You have the foundation to create any application you can dream up.
36.2 The Possibilities/A Pet Project
So where should you go from here? Remember that programming is an art. You gain skill primarily by applying that art. If you do not apply it, you will lose your skill. As such, you need to exercise this art. There are many ways you can do this. The most important thing for you to do though is to pick a project. It does not have to be a really big project. If it is small, when you complete it you will simply pick another one. However, having a project outside of your normal course work gives you a great way to further develop your skills. It also allows you to build a portfolio of your work.
When you pick a project, you will need to look into what it takes to do it. Not all projects will favor you working in Scala. That is not a problem. Learning another language is a great exercise. It is always easier to learn the second than it was to learn the first and having knowledge of multiple languages often helps you to see problems from different perspectives. There are many types of projects that you can do in Scala though. Consider these possibilities.
36.2.1 General 2-D Application
What you know how to do best at this point is write applications. If you can think of something that interests you that works as an application, run with it. Whether it is something useful or just something for fun, there are vast possibilities in what you can get a computer to do. Take advantage of your ability to do graphics and GUIs. Make something networked or push the parallelism to fully utilize newer hardware.
36.2.2 3-D Application
If you are playing with graphics, you might want to do something in 3-D. You can render things in 3-D with ray tracing or other techniques that work in 2-D. However, if you are willing to do a bit of extra reading, which you should be, you can use Scala to write full 3-D applications through some different Java libraries.
The most standard 3-D graphics library is OpenGL®. There are several Java-based wrappers for OpenGL. The most established of these is called JOGL, the Java bindings for OpenGL. OpenGL takes advantage of 3-D hardware to make 3-D rendering fast.
The primary downfall of OpenGL is that it is a low-level API. That means you are setting up geometry and giving instructions to render it in a way that is close to what the machine wants. There are also higher level libraries like Java3D®. These use scene graph representations and can often be easier to use when you want to get things up and running.
New libraries are being written all the time. As of this writing, there are at least two different 3-D graphics libraries being developed specifically for Scala, including Sgine. More options will inevitably become available over time.
36.2.3 Mobile
Not all applications have to run on desktop machines the way we have been working either. Mobile has become a huge market and you can do mobile development in Scala as well. The Android® platform from Google® uses Java for development by default, but it can work just as well with compiled Scala code as well. There is a project called "Scala for Android" that is being developed to help make it easier to put Scala programs on Android phones. This opens up phone and tablet options. The openness of the Android environment means that you can easily develop something to share with others.
36.2.4 Web
Even on the desktop, many people do not use standard applications most of the time. Many of the things that you do on a computer have moved into the web browser. Rich web applications provide a very desktop-like feel with responsive user interactions, but they actually occur in the browser with information being stored out on the web.
You can use Scala for web development as well. Most of the large, well-known companies that use Scala at the time of this writing are in the web application field. The Lift® framework was the first web framework written specifically for Scala. By the time this book is published, version 2.0 of the Play! framework should also be available and should be part of the Typesafe stack. Version 2.0 of Play! has been written from the ground up for Scala and to take advantage of how Scala works. Typesafe support means that you can expect it to integrate nicely with other major pieces of the Scala tool set.
36.2.5 GPGPU
In chapter 21 we looked at how you can use Scala to take advantage of multicore processors. New computers have more than just multicore processors though, they also have programmable graphics cards or processing units built into their CPUs that include graphics card style circuitry. In fact, a high-end gaming machine generally have more brute force computing power on the graphics card than in the normal processor. It is possible to write programs that take advantage of this processing power and do number crunching on graphics cards.
One standard for doing this type of work is OpenCL®. It is a library/language from the same group that created OpenGL. Just as JOGL is a Java binding for OpengGL, there is a Java binding for OpenCL called JavaCL that you can use to do low-level coding for Graphics Processing Units (GPUs) in Java and, therefore, in Scala as well. In addition, there is also a Scala addition currently under development called ScalaCL. Using ScalaCL, you can make collections that are similar to the parallel collections, but instead of using multiple threads on multicore machines, they take advantage of GPUs.
36.2.6 AI, NLP, and Machine Learning
There are also libraries available that can get you up and running quickly on Artificial Intelligence (AI), Natural Language Processing (NLP), and machine learning. Remember that any library written for Java can be called easily in Scala as well. With just a little searching you can find libraries that parse English and help you derive meaning from plain written text or that can be trained to identify patterns in images.
36.2.7 Open-Source and More
If you are not certain about a program you can always look to see what other people are doing. Consider joining an open-source project. Contributions to open-source not only help out lots of people, they look great on resumes. There are open-source projects working on almost anything you can imagine and likely many things you have not imagined. You just have to go looking for them.
The bottom line is that the computer is a remarkably powerful machine and you have just taken your first steps into a world where you can control these machines to do what you want. Embrace this capability and take some time to make something wonderful.
36.3 End of Chapter Material
36.3.1 Exercises
- Back in project 2 (p.14) you were asked to compare programming to three other activities based on an extremely limited introduction. Now that you have significantly more experience, revisit that same question.
- Look up one of the technologies mentioned in this chapter and install whatever additional files/projects you need to use it.
- Try writing a small example program for the technology you selected for the last exercise.
36.3.2 Projects
At this point you should have built at least one project which includes a significant amount of code and functionality. Now is the time to finish it off. Add any features that you had been putting off earlier and polish it up so that it has the desired functionality.