package ch02.item07;
import java.util.Map;
import java.util.WeakHashMap;
public class WeakHashMapTest {
public static void main(String[] args) {
Map<Integer, Stack> weakMap = new WeakHashMap<>();
Stack s1 = new Stack();
Stack s2 = new Stack();
weakMap.put(20, s1);
weakMap.put(450, s2);
for (Map.Entry<Integer, Stack> elem : weakMap.entrySet()) {
System.out.printf("%d: %s\n", elem.getKey(), elem.getValue());
}
s2 = null;
System.gc();
for (Map.Entry<Integer, Stack> elem : weakMap.entrySet()) {
System.out.printf("%d: %s\n", elem.getKey(), elem.getValue());
}
}
}