Question

How to use static member variable to count object instances in Java

Answer 1

class Counter {
  
    static int counter = 0;
 
    public Counter() {
        counter++;
    }
 
    public int ShowObjectNumber() {
        return counter;
    }
}

  
public class MyClass {
 
    public static void main(String[] args) {
  
        Counter o1 = new Counter();
        System.out.println(o1.ShowObjectNumber());
 
        Counter o2 = new Counter();
        System.out.println(o2.ShowObjectNumber());
        
        Counter o3 = new Counter();
        System.out.println(o2.ShowObjectNumber());
    }
}





  
/*
 
run:
 
1
2
3

*/

 
}
 
/*

run:

1
2

*/

 

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