How to ensure finalize() is always called (Thinking in Java exercise)

Question

I\'m slowly working through Bruce Eckel\'s Thinking in Java 4th edition, and the following problem has me stumped:

Create a class with a fina

Answer 1

run new constructor() and System.gc() more than twice.

public class Horse {
    boolean inStable;
    Horse(boolean in){
        inStable = in;
    }   
    public void finalize(){
        if (!inStable) System.out.print("Error: A horse is out of its stable!");
    }
}
public class MainWindow {
    public static void main(String[] args) {
        for (int i=0;i<100;i++){
            Horse h = new Horse(false);
            h = new Horse(true);
            System.gc();
        }
    }
}