1. public class InstanceCounter {
    2.    private static int numInstances = 0;
    3.    protected static int getCount() {
    4.       return numInstances;
    5.    }
    7.    private static void addInstance() {
    8.       numInstances++;
    9.    }
    11.    InstanceCounter() {
    12.       InstanceCounter.addInstance();
    13.    }
    15.    public static void main(String[] arguments) {
    16.       System.out.println("Starting with " +
    17.       InstanceCounter.getCount() + " instances");
    18.       for (int i = 0; i < 500; ++i){
    19.          new InstanceCounter();
    20.           }
    21.       System.out.println("Created " +
    22.       InstanceCounter.getCount() + " instances");
    23.    }
    24. }

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