1 | /* |
2 | * $Id: AssertNoReference.java,v 1.1.1.5 2004/05/25 20:23:30 hastings Exp $ |
3 | * |
4 | * (c) Copyright, Moebius Solutions, Inc., 2004 |
5 | * |
6 | * All Rights Reserved |
7 | * |
8 | * This material may be reproduced by or for the U. S. Government |
9 | * pursuant to the copyright license under the clause at |
10 | * DFARS 252.227-7014 (OCT 2001). |
11 | */ |
12 | |
13 | package com.moesol.ref; |
14 | |
15 | import java.lang.ref.WeakReference; |
16 | |
17 | /** |
18 | * Allow assertions to be made about strong object references. |
19 | * <pre> |
20 | * Object test_object = new Object(); |
21 | * AssertNoReference ref_check = new AssertNoReference(test_object); |
22 | * // use test_object |
23 | * test_object = null; |
24 | * assert(!ref_check.isReferenced()); |
25 | * </pre> |
26 | */ |
27 | public class AssertNoReference extends WeakReference { |
28 | public AssertNoReference(Object referent) { |
29 | super(referent); |
30 | } |
31 | /** |
32 | * @return true if there are strong references to |
33 | * <code>referent</code>. |
34 | */ |
35 | public boolean isReferenced() { |
36 | // Without this yield the gc would fail to mark some |
37 | // references as finalizable. |
38 | Thread.yield(); |
39 | // Force a garbage collection cycle to be sure that newly |
40 | // finalizable references are found. |
41 | System.gc(); |
42 | return null != get(); |
43 | } |
44 | } |