question: public static void appendProperty ( String propertyName , String value ) { String oldValue = props . getProperty ( propertyName ) ; if ( oldValue != null && ! oldValue . equals ( "none" ) ) { oldValue += "," + value ; } else { oldValue = value ; } props . setProperty ( propertyName , oldValue ) ; }
target:  Appends a property via a comma separated list <p> If the property does not exist, it adds it.