But if you specify a parametrized constructor like Demo(int a) ,and want to use the default constructor Demo(), it is mandatory for you to specify it. In other words, in case your Constructor is ...

10 types of Java constructors. There is a variety of different types of constructors in Java, and each constructor type has its own special use case and is subject to its own specific set of rules.

In this example, the prepareByteArray method processes the Certificate object before passing it to the SuperClass constructor. With JEP 447, this process becomes more streamlined and intuitive.

The next class, Employee, is a contrived example of a class in which the extensible class’s constructor calls an overridable method (setSalaryRange()). Employee.java ...