When Nucleus creates a component from a properties file, Nucleus calls the component’s constructor, which takes no arguments. This means that the component must be declared as a public
class, and the component must have a public
constructor that takes no arguments. The Person
class, for example, defines such a constructor:
public Person () {}
Even if a component does nothing, this constructor must be defined in order for Nucleus to be able to create the component from a properties file.