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[CC150v4] 14.1 Java Private Constructor


In terms of inheritance, what is the effect of keeping a constructor private?


If the programmer does not provide a constructor for a class, the system will always provide a default, public no-argument constructor.

To disable this default constructor, simply add a private no-argument constructor to the class.

Two categories of usage:

  1. Object construction is entirely forbidden
    1. class offers only static members (sometimes called utility class)
  2. Object construction is private only
    1. a class needs to prevent the caller from creating objects, like Singleton