Instance versus static methods
Each
Java method is either an instance method or a static method. Any method not marked with the static keyword is an instance method. Lastly, all Java methods must be defined within a class. In order to call an instance method, you must first have an instance of the class within which the method you want to call is defined. Suppose we want to call an instance method named "method1" defined in class "ClassA". We could do the following:
ClassA x = new ClassA();
x.method1();
If method1 were instead static, then we would call the method by referring directly to the class itself:
ClassA.method1();
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