What is the usage method of static class in Java?

In Java, a static class refers to an inner class that is declared as static. Here is how it is used specifically:

1. Declare a static class: Within the outer class, use the static keyword to declare it using the syntax: static class ClassName.
2. Creating an instance of a static class: Because a static class is separate from the outer class, you can directly create an instance by using the class name without needing to create an instance of the outer class. The syntax is: OuterClass.StaticClass staticObj = new OuterClass.StaticClass().
3. Accessing members of a static class: Access the member variables and methods of a static class through an instance of the static class.

It is important to note that a static class can only access static members of the outer class, not non-static members. Additionally, a static class cannot access instance variables or methods of the outer class, and cannot use the “this” keyword to reference instances of the outer class.

Static classes are primarily used to organize and manage code, grouping related functionalities together to enhance the code’s readability and maintainability.