What is your preferred scripting language in java world (scripting language on JVM) and way?

Question

What is your preferred scripting language in java world (scripting language on JVM) and way? When do you prefer your scripting language over java (in what situations for example for prototyping)? Do you use it for large projects or for personal projects only?

Answer 1

For me, Clojure wins hands down. Being a Lisp, it's concise and dynamically typed, it has enormous expressive power so I can write a lot of functionality in a few lines. And its integration with Java is unsurpassed – I'm only partly joking when I say Clojure is more compatible to Java than Java itself. As a result, the entire breadth of Java libraries, both from the JDK and 3rd party, is fully useable.

Finally, with a little care Clojure code can be as fast as Java code, so I'm not even losing performance.

Answer 2

My favorite is Jython, and I use it by embedding a Jython interpreter in my Java application. It is being used in commercial projects, and it allows to easily customize the application according to the customers' needs without having to compile anything. Just send them the script, and that's it. Some customers might even customize their application themselves.

Answer 3

I've successfully used Groovy in a commercial project. I prefer scripting languages because of duck typing and closures:

def results = []
def min = 5
db.select(sql) { row ->
    if (row.value > min)
        results << row;
}

Translation: Run a SQL query against the database and add all rows where the column "value" is larger than "min" to "result". Note how easily you can pass data to the inner "loop" or get results out of it. And yes, I'm aware that I could achieve the same with SQL:

def results = []
def min = 5
db.select(sql, min) { row ->
    results << row;
}

(just imagine that the String in "sql" has a "?" at the right place).

IMHO, using a DB with a language which doesn't offer rich list operations (sort, filter, transform) and closures just serves as an example how you should not do it.

I'd love to use Jython more but the work on Jython 2.5 has started only recently and Python 2.2 is just too old for my purposes.

Answer 4

I might prefer Scala, but I can't say, still learning. At the moment using Groovy to write small utility programs. Haven't tried even Groovy on Grails. Heard lots of good about Lift Framework for Scala as well.

Answer 5

JavaScript Rhino has a compelling advantage -- it is included with the JDK. That being said, later versions of Rhino than the one with Java 6 have nice features like generators, array comprehensions, and destructuring assignment.

I favor using it whenever the ceremony of handling Java exceptions clutters up the code for no real benefit. I also use it when I want to write a simple command-line script that takes advantage of Java libraries.

Answer 6

Java. Seriously. It's a powerful, easy-to-use (if a tad verbose) language that everybody knows. The integration with Java is great.

Answer 7

How about SISC (Second Intepreter of Scheme Code)?

REF: http://sisc-scheme.org/

Answer 8

The company I work for embeds Groovy into a Java/Spring website, which is deployed on a number of sites. The scripts are stored externally of the compiled WAR file, and allow us to manipulate some of the site logic without having to roll out new WAR's to each site. So far, this approach has worked very elegantly for us.

A particularly nice feature of Groovy is that it can closely resemble Java code, which makes it very easy to port existing Java classes to it.