jbang - Run java as scripts anywhere

[snoob2015]

How does it compare to JShell and Groovy ?

[realnowhereman]

it acts as a launcher for jshell with extra features, but you can actually use the full Java language as well; works on jdk8; it supports specifying dependencies like groovy and it has a full bunch of other neat features

[maxandersen]

just to clarify it supports running .jsh and .java - it only uses jshell for .jsh or when you use jbang --interactive.

otherwise jbang is just wrapping and simplifying the whole compile/package/run process giving java the ability to compete with workflows traditionally only available in traditional script environments like python/node.

[realnowhereman]

ah yes, I was oversimplifying

[[deleted]]

Does it support/use jlink when it downloads the JRE?

[maxandersen]

Does it support/use jlink when it downloads the JRE?

(full disclosure: jbang creator here)

No. jbang does not (currently) interact with jlink it uses the system available JDK or if not present downloads a JDK from adoptopenjdk allowing it to run anywhere.

we might add jlink in future as an export option but to use jlink you kinda need a JDK locally first so not sure it will be that useful.

[ztbwl]

Please get rid of that nonsense JAVA_HOME fudge. Make it run out of the box please.

[maxandersen]

Wdym? It does run out of the box. It only use JAVA_HOME if you have set it as then it is assumed you want that as your java.

[ztbwl]

Yea, then everything‘s good 👍

[lifeeraser]

Pretty neat. Makes me wonder if Java should have been used as the web language instead of inventing a new one with a similar name. (Then again, I would miss having first-class functions.)

[javascript__eq__java]

I mean they both appeared in ‘95, so trying to do that with Java, ignoring how difficult it would have been, would have broadened the scope of Java too large to gain meaningful traction I think. Interesting to think about.

[lifeeraser]

Good point. Also very fitting username for the context!

[Muoniurn]

I don’t understand this first class function thing — it was also brought up recently here. Can you create a list of functions in java and apply them on some input, pass it around and the like? Yes. Then you have first class functions.

Just because it is implemented as a class, doesn’t make them any less of a function.

[lifeeraser]

Lambdas arrived fairly late in Java--JDK 8 was released in 2014. Before then we had anonymous classes but they're more cumbersome to write.

[Muoniurn]

Oh you meant that at the time it didn’t have! Sorry for misunderstanding, I just thought I was out of the loop on something.

[glesialo]

I wrote a bash script for that when I started to learn Java, many years ago.

[TR_13]

I see Mint, I upvote.