Java对象自我拯救过程 

 1 public class GCtest {
 2 /**
 3  *
 4  * 任何对象的finalize方法只会被系统自动调用一次
 5  * 
 6  * */
 7     
 8     public static GCtest gctest = null;
 9     
10     public void isAlive(){
11         System.out.println("yes ! i am still alive :) ");
12     }
13     
14     @Override
15     protected void finalize() throws Throwable {
16         // TODO Auto-generated method stub
17         super.finalize();
18         System.out.println("finalize mehtod executed");
19         GCtest.gctest = this;
20     }
21     
22     public static void main(String[] args) throws Exception {
23         // TODO Auto-generated method stub
24         gctest = new GCtest();
25         //第一次自救
26         gctest = null;
27         System.gc();
28         //finalize 优先等级比较低
29         Thread.sleep(500);
30         if(gctest != null){
31             gctest.isAlive();
32         }else{
33             System.out.println("yes ! i am dead :(");
34         }
35         
36         //第二次自救 代码一样 但失败了
37         gctest = null;
38         System.gc();
39         //finalize 优先等级比较低
40         Thread.sleep(500);
41         if(gctest != null){
42             gctest.isAlive();
43         }else{
44             System.out.println("yes ! i am dead :(");
45         }
46         
47         
48     }
49 
50 }

 

posted @ 2015-07-06 16:57  韩不懂  阅读(238)  评论(0)    收藏  举报