Using optional options

There might be cases when you have to use certain options only under specific conditions as for example you would like to enable debugging only when you set a system property. In order to fulfill such an requirement you can use optional composite option as in the following example:

@Configuration
public static Option[] configure()
{
    return options(
        when( Boolean.getBoolean( "isDebugEnabled" ) ).useOptions(
            vmOption( "-Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005" ),
            timeout( 0 )
        )
    );
}

In the above example the vmOption and timeout options will be included only when there is a system property named 'isDebugEnabled' with a value of 'true'.

If you are using Maven you can then use the following to switch the debug options on:

mvn install -DisDebugEnabled=true

The condition is not limited to just system properties. You can use any expression that evaluates to a boolean or define your own condition.