JCommander select only one parameter of a set

Question

I was trying to obtain the following command line configuration:

myprogram.jar --op1 --other parameters  OK  
myprogram.jar --other parameters --op2  OK  
myprogram.jar --op1 --op2 should launch ParameterException

I don't want to set --operation=[1|2] cause they are very different type of operations
Is there a way to obtain this with JCommander?

score 2 · Accepted Answer · answered Jan 07 '22 at 08:54

I think what you're looking is to validate the parameters globally.

Unfortunately JCommander does not support it, with simple annotations. As found in its documentation: http://jcommander.org/#_global_parameter_validation

For this you need to write your own validator after parsing parameters, such as below example:

import com.beust.jcommander.JCommander;
import com.beust.jcommander.Parameter;
import com.beust.jcommander.ParameterException;

class Main {
    @Parameter(names = "-op1")
    private final boolean op1 = false;

    @Parameter(names = "-op2")
    private final boolean op2 = false;

    public static void main(String[] args) {
        Main main = new Main();
        JCommander.newBuilder()
                .addObject(main)
                .build()
                .parse(args);
        main.run();
    }

    public void run() {
        if (op1 && op2) {
            throw new ParameterException("Choose only either op1 or op2, but not both");
        }
    }
}

JCommander select only one parameter of a set

1 Answers1