why cannot use "this" in the main method?

java

Solution

`this` refers to the current object. However, the `main` method is static, which means that it is attached to the class, not to an object instance, hence there is no current object inside `main()`.

In order to use `this`, you need to create an instance of your class (actually, in this example, you do not use `this` since you have a separate object reference. But you could use `this` inside your `m()` method, for example, because `m()` is an instance method which lives in the context of an object):

public static void main(String[] args){
    example e = new example();
    int c=e.a;
}

By the way: You should get familiar with the Java naming conventions - Class names usually start with a capital letter.

Problem

Original source