constructor can have any access specifiers.. as the person abv me said.. and comming to private u need a public static method for that class so that u can get into that class and then call the constructor. this is wat private deals with..
and i have not come accross any spl use of declaring any constructor as protected.. if it is a normal method which is protected then it is ok... i am not sure of protected constructor...
Protected members--methods, variables, constructors, and inner classes--are available to all classes in the same package as the declaring class (whether subclass or not) and to all subclasses of the declaring class (whether same package or not).