JVM FinalizeEscapeGC

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
public class FinalizeEscapeGC {
    public static FinalizeEscapeGC SAVE_HOOK = null;

    public void isAlive() {
        System.out.println("Yes, i am still alive :)");
    }

    @Override
    protected void finalize() throws Throwable {
        super.finalize();
        System.out.println("finalize method executed!");
        FinalizeEscapeGC.SAVE_HOOK = this;
    }

    public static void main(String[] args) throws Throwable{
        SAVE_HOOK = new FinalizeEscapeGC();

        SAVE_HOOK = null;
        System.gc();
        Thread.sleep(500);
        if (SAVE_HOOK != null) {
            SAVE_HOOK.isAlive();
        }else {
            System.out.println("no, i am dead :(");
        }

        SAVE_HOOK = null;
        System.gc();
        Thread.sleep(500);
        if (SAVE_HOOK != null) {
            SAVE_HOOK.isAlive();
        }else {
            System.out.println("no, i am dead :(");
        }
    }
}

1
2
3
finalize method executed!
Yes, i am still alive :)
no, i am dead :(