/**
?*?This?class?is?used?only?as?a?“null“?argument?for?Javadoc?when?comparing
?*?two?API?files.?Javadoc?has?to?have?a?package?.java?or?.class?file?as?an
?*?argument?even?though?JDiff?doesn‘t?use?it.
?*/
public?class?Null?{
????public?Null（）?{
????}
}