import java.util.*;
import java.text.*;
class User{
public static User user = null;
@Override
protected void finalize() throws Throwable {
System.out.println("User-->finalize()");
user = this;
}
}
class FinalizerTest {
public static void main(String[] args) throws InterruptedException {
User user = new User();
user = null;
System.gc();
Thread.sleep(1000);
user = User.user;
System.out.println(user != null);//true
user = null;
System.gc();
Thread.sleep(1000);
System.out.println(user != null);//false
}
}