Difference between static and non static methods in java
A static method belongs to the class and a non-static method belongs to an object of a class. Static methods are useful if you have only one instance where you're going to use the method, and you don't need multiple copies (objects). Non-static methods are used if you're going to use your method to create multiple copies.
A static method can however be called both on the class as well as an object of the class. A static method can access only static members. A non-static method can access both static and non-static members because at the time when the static method is called, the class might not be instantiated.