how to define a constructor code example

Example: type of constructor in java

There are three types of constructors: 
Default, No-arg constructor and Parameterized.
  
If you do not implement any constructor in your class,
Java compiler inserts a default constructor into your code on your behalf.
This constructor is known as default constructor.
  
Constructor with no arguments is known as no-arg constructor

Constructor with arguments(or you can say parameters) is known as 
Parameterized constructor.