JarCastingargs4j-helpers
Simple helper for command-line parsing using args4j.
Args4j is a fantastic parsing library, but there's typically a lot of boilerplate for dealing with printing usage and dealing with parse errors.
This library encapsulates typical option parsing error handling:
- If help (provided via
OptionWithHelpbase trait bound to--helpand-h) is requested, print usage information to stderr, exit with code0. - If a required option is missing (
required=true), print usage information to stderr, exit with code1(unless help was requested).
Usage
Define your options class normally, extending OptionsWithHelp
class MyOptions extends OptionsWithHelp {
@Option(name="--blah", aliases=Array("-b"), usage="some val", metaVar="BLAH")
var blah: Int = 0
}
retrieving/parsing becomes a single line
import OptionHelper.optionsOrExit
def main(args: Array[String]) {
val options = optionsOrExit(args, new MyOptions)
println(s"blah is ${options.blah}")
}