What is a constructor with no argument?

Java doesn’t require a constructor when we create a class. However, it’s important to know what happens under the hood when no constructors are explicitly defined. The compiler automatically provides a public no-argument constructor for any class without constructors . This is called the default constructor.

The arguments of a constructor can only be found by type, not by name, so there is no way for the framework to reliably match properties to constructor args . Therefore, they require a no-arg constructor to create the object, then can use the setter methods to initialise the data.

A constructor that takes no parameters is called a parameterless constructor . Parameterless constructors are invoked whenever an object is instantiated by using the new operator and no arguments are provided to new .

A Constructor with arguments(or you can say parameters) is known as Parameterized constructor . As we discussed in the Java Constructor tutorial that a constructor is a special type of method that initializes the newly created object.