Dynamic Parameters are getting ignored when using the @ syntax to pass in parameters

[ThomasDekeyser]

Using JCommander 1.72 No issues when passing dynamic parameters directly in the cmdline. But moving these into a separate file using the @syntax will make JCommander ignoring these params.

I think the issue is related to following codelines.

JCommander, L422
private String[] expandArgs(String[] originalArgv) {
    List<String> vResult1 = Lists.newArrayList();

    //
    // Expand @
    //
    for (String arg : originalArgv) {

        if (arg.startsWith("@") && options.expandAtSign) {
            String fileName = arg.substring(1);
            vResult1.addAll(readFile(fileName));
        } else {
            List<String> expanded = expandDynamicArg(arg);
            vResult1.addAll(expanded);
        }
    }

[cbeust]

Can you provide a failing example?

[ThomasDekeyser]

After isolating the code i was better able to discover the problem. When using the default separator (a space), then the external parameter file using the @-syntax must contain new-lines

-t
whatever
-P
param1=value1
-P
param2=value2

When using a non-default separator, example colon : , then the external parameters file can look like

-t:whatever
-P:param1=value1
-P:param2=value2

but also working is

-t
whatever
-P
param1=value1
-P
param2=value2

I was a bit confused by this behavior that i considered this as an issue. Up to you if you agree with this. At least, not an issue for me any more.

Test Java class used.

package com.tde;

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

import java.util.HashMap;
import java.util.Map;

public final class Main {

    public static void main(String... args) {
        Main main = new Main();
        main.process(args);
    }

    void process(String... args) {
        final InputParameters parameters = new InputParameters();
        final JCommander commander = new JCommander(parameters);
        commander.setAcceptUnknownOptions(true);
        try {
            commander.parse(args);
            logInputParameters(parameters);
        } catch (final ParameterException e) {
            System.err.println("Parameter parsing exception");
            System.err.println(e.getLocalizedMessage());
            final StringBuilder out = new StringBuilder();
            commander.usage(out);
            System.err.println(out.toString());
            throw e;
        }

    }

    private void logInputParameters(InputParameters parameters) {
        System.out.println("param t : "+parameters.getMyParam());
        for (Map.Entry<String, String> entry : parameters.getDynamicParameters().entrySet()) {
            System.out.println("param p:  "+entry.getKey() + "->"+entry.getValue());
        }
    }


    //@Parameters(separators = ":")
    class InputParameters {

        @Parameter(names = {"-t"}, description = "Another parameter", required = true)
        private String myParam;

        @DynamicParameter(names = "-P", description = "Dynamic parameters examples")
        private Map<String, String> dynamicParameters = new HashMap<>();

        public String getMyParam() {
            return myParam;
        }

        public Map<String, String> getDynamicParameters() {
            return dynamicParameters;
        }
    }
}

[ThomasDekeyser]

Hi Cedric,

Example added. Not sure however if you consider this an issue or not.

Regards, thomas

On Thu, Sep 21, 2017 at 6:04 PM, Cedric Beust [email protected] wrote:

Can you provide a failing example?

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/cbeust/jcommander/issues/401#issuecomment-331203675, or mute the thread https://github.com/notifications/unsubscribe-auth/AKbKYFDQyWfhniq0zqKpTtNkm36BCAzuks5skokogaJpZM4PfeNh .