How to use Java's default constructor. Although the default constructor in Java is convenient and easy to use, developers must understand some important rules about its existence and implementation.

The drawback to Java's default constructor is that its initializations are fairly meaningless: Reference types are initialized to null. Primitive number types are initialized to 0. Primitive boolean ...

Classes, fields, methods, constructors, and objects are the building blocks of object-based Java applications. This Java tutorial teaches you how to declare classes, describe attributes via fields ...

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 ...