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23 
24 /* @test
25  * @bug 4076283
26  * @summary java.lang.ref.SoftReference should reliably prevent
27  *          OutOfMemoryErrors
28  * @author Peter Jones
29  * @author Mark Reinhold
30  */
31 
32 /* If this test fails, an OutOfMemoryError will be thrown */
33 
34 import java.lang.ref.SoftReference;
35 
36 
37 public class Bash {
38 
39     static class TestReference extends SoftReference {
40 
41         public static TestReference head;
42         public TestReference next;
43 
TestReference(Object referent)44         public TestReference(Object referent) {
45             super(referent);
46             next = head;
47             head = this;
48         }
49     }
50 
51 
52     static final int NUM_BLOCKS = 2048;
53     static final int BLOCK_SIZE = 32768;
54 
55 
main(String[] args)56     public static void main(String[] args) throws Exception {
57 
58         for (int i = 0; i < NUM_BLOCKS; ++ i) {
59             TestReference ref = new TestReference(new byte[BLOCK_SIZE]);
60         }
61 
62         int emptyCount = 0;
63         int fullCount = 0;
64         for (TestReference r = TestReference.head; r != null; r = r.next) {
65             if (r.get() == null) emptyCount++;
66             else fullCount++;
67         }
68 
69         System.err.println(fullCount + " full, " + emptyCount + " empty ");
70 
71     }
72 
73 }
74