User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0
Hi,
maybe you can do it with the "presentValue"
/**
* The default value of the parameter if its name is present on the
* command line. If this value is specified, then the command parsing
* will not expect a value on the command line for this parameter.
* If this value is UNSPECIFIED, then an argument must be specified on the
* command line for the parameter.
* @return default value of the parameter if its name is present on the
* command line.
**/
String presentValue() default UNSPECIFIED;
For arguments that are truly required you can see the use
of the REQ constant to show that.
I can understand your approach if maybe dealing with a
single argument, but here we cleary need the ability to
specify absentValue=null or equivalent for some of the
parameters, which is where we're struggling to match the
specification.