Scala from the world Java
Posted January 21, 2013on:
Scala is a statically typed and multi-paradigm programming language that runs on Java virtual machine and provides Java like syntax with a few improvements.
Being a multi-paradigm programming language, Scala allows for mixing multiple programming styles such as object oriented, imperative and functional programming. Whether it’s good or not, it is not a question that could be answered with a yes or no. Supporters would say that programmers can choose from a variety of styles and stick to the best depending on their needs. The others would argue that putting together some features found in many other programming languages can’t work well, mostly by increasing complexity and making a programming language obscure.
Scala code compiles to a byte code and runs on Java virtual machine, thus it is compatible with other Java applications. If most of your code and libraries are from Java world, this can be nothing but a good thing. At the same time some additional complexity in Scala is dictated by assuring compatibility with Java.
For some developers the Scala code is obscure, for others could be a nice and neat form of solving some specific problems.
One more positive aspect of Scala is its conciseness. We all know how Java verbose is and how many boiler code developers write everyday including constructors, getters, variable initialisation (type and generics), semicolons and many others.
Now let’s see some other aspects of working with Scala:
At first sight the performance in Scala is very good, comparable to Java. Scala code compiles to the same byte code as Java does and runs on the same Java virtual machine. Still how fast Scala code is may vary from case to case and usually it’s up to the way how the code is written. The awareness of how to write a high performance Scala code is especially important for Java developers who are not very experienced in both Scala and functional programming.
There are not too many development tools created specifically to serve Scala, but fortunately, thanks to compatibility with Java it doesn’t look so bad. One family of tools hardly usable in Scala are those, which do some sort of code analysis, for instance code coverage and static code analysis. Static code analysis tools are even less usable.
The two worth to mention native Scala extensions are Lift web framework and Akka actors platform.
The majority of libraries and frameworks from a Java world, should be possible to use quite smoothly, which among other things, is thanks to implicit conversions in Scala.
Interoperability between Scala and other programming languages, including Java/C/C++, is very good, mostly because of running on Java virtual machine. What Java may talk to, Scala can do as well. Taking into account support for implicit conversions described above, I would state that Scala is one of the leaders of interoperability among all programming languages.
Developers are provided with all they need to test Scala applications efficiently. To follow a Test Driven Development methodology, they can use popular in Java world Junit tool. If someone is more keen on Behaviour Driven Development then ScalaTest is a way to go.
Monitoring and maintenance
One of the main monitoring tools to analyze production Scala applications is JMX (Java Management Extensions). This tool does its job well when we want to analyse some predefined statistics, but sometimes we need to investigate some aspects of a production application while it’s running and JMX can’t provide all required data. To deal with such scenarios, Java provides Java Virtual Machine Tool Interface (JVM TI) that allows for inspecting running Java applications but it can be used for Scala too.
Scala community, including forum, mailing list and blogs, is not the biggest in the world, but it’s very energetic. Most people who are part of a Scala community are very passionate developers, which are always happy to help others to solve their problems. Books are also great: Programming in Scala book by Marting Oderski, Lex Spoon and Bill Venners.
No one will argue that it is far behind other programming languages such as Java or C/C++. Still while looking for Scala developers we could search for Java developers with Scala interests as well. The learning curve is not massive as Scala follows Java syntax. In such case, at least on experienced Scala developer would help the team adopting new programming language.
Have you moved from Java to Scala? How do you find this language?
Thanks for sharing your opinion!