difference between class and interface in java
A class can be instantiated by creating its objects. An interface is
never instantiated as the methods declared inside an interface are abstract
and does not perform any action, so there is no use of instantiating any
interface.
A class is declared using a keyword class. In the same way,
an interface is created using a keyword interface.
The members of a class can have access modifier like public, private, protected.
But the members of an interface are always public as they have to be accessed
by the classes implementing them.
The methods inside a class are defined to perform an action on the fields
declared in the class. The methods inside an interface are purely abstract.
A class can implement any number of interfaces but can extend only one
super class.
An interface can extend any number of interfaces but cannot implement any
interface.
A class has constructors defined inside it to get the variable initialized.
But, an interface does not have any constructors as there are no fields
to be initialized. The fields of an interface are initialized
at the time of their declaration only.
