[SOLVED] Commons CLI empty Options in CommandLine

Commons CLI empty Options in CommandLine

I don't understand how to apply Options to DefaultParser in Commons CLI.

When CommandLine object is created, assigned Options is always empty.

Bellow block of code is how i interpreted Commons CLI docs:

public static void main(String[] args)  {

    Options options = new Options();

    options.addOption("c", false, "why are you hidding from me");

    CommandLineParser parser = new  DefaultParser();

    System.out.println(args[0]); // this prints -c

    try {

        CommandLine line = parser.parse(options, args);

        System.out.println(line.getArgs()[0]); // prints -c

        Option[] o = line.getOptions(); // this is empty for some reason

        System.out.println(o.length); // prints 0

        if (line.hasOption("c")) { // false

            System.out.println(" flag c found");
        }
    }

    catch(ParseException e ) {
        e.printStackTrace();
    }

How come that line.getOptions() is empty, and how to apply the options properly ?

Solution

I just tried to reproduce your issue but everything was OK for me. I created a simple maven project with only the commons-cli:commons-cli:1.3.1 dependency and a Test main class with the exact same method you provided in your question.

When I compile and run the main method from the Windows command line, e.g. with:

java -cp .;[path_to_commons_cli_jar]/commons-cli-1.3.1.jar Test -c

then it gave me the expected output:

args is made of the single "-c" value;
line.getArgs() returns an empty array;
line.getOptions() returns an single entry array consisting of the expected Option object.

Maybe there are some remaining spaces that aren't stripped in the command line you use when you launch your program within eclipse? Otherwise, your code should work fine...