Java already supports this dynamic instantiation of classes using Class.newInstance(). However, this only works if the class has an appropriate constructor. There are many times when a class cannot be instantiated this way, such as when the class contains:

* Constructors that require arguments.
* Constructors that have side effects.
* Constructors that throw exceptions.

As a result, it is common to see restrictions in libraries stating that classes must require a default constructor. Objenesis aims to overcomes these restrictions by bypassing the constructor on object instantiation.