test/java/io/Serializable/clearHandleTable/ClearHandleTable.java

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  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /* @test
  25  * @bug 4332184
  26  * @summary Ensure that ObjectOutputStream properly releases strong references
  27  *          to written objects when reset() is called.
  28  */
  29 
  30 import java.io.*;
  31 import java.lang.ref.WeakReference;
  32 import java.util.ArrayList;


  33 
  34 public class ClearHandleTable {


  35     public static void main(String[] args) throws Exception {
  36         final int nreps = 100;
  37         ObjectOutputStream oout =
  38             new ObjectOutputStream(new ByteArrayOutputStream());
  39         WeakReference[] refs = new WeakReference[nreps];
  40 
  41         for (int i = 0; i < nreps; i++) {
  42             String str = new String("blargh");
  43             oout.writeObject(str);
  44             refs[i] = new WeakReference(str);
  45         }
  46 
  47         oout.reset();
  48         exhaustMemory();
  49 
  50         for (int i = 0; i < nreps; i++) {
  51             if (refs[i].get() != null) {
  52                 throw new Error("failed to garbage collect object " + i);







  53             }
  54         }






  55     }
  56 
  57     static void exhaustMemory() {
  58         ArrayList blob = new ArrayList();
  59         try {
  60             for (;;) {
  61                 blob.add(new int[0xFFFF]);
  62             }
  63         } catch (OutOfMemoryError e) {
  64         }
  65     }
  66 }


  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /* @test
  25  * @bug 4332184
  26  * @summary Ensure that ObjectOutputStream properly releases strong references
  27  *          to written objects when reset() is called.
  28  */
  29 
  30 import java.io.*;
  31 import java.lang.ref.WeakReference;
  32 import java.util.ArrayList;
  33 import java.util.Iterator;
  34 import java.util.List;
  35 
  36 public class ClearHandleTable {
  37     private static final int TIMES = 1000;
  38 
  39     public static void main(String[] args) throws Exception {
  40         final int nreps = 100;
  41         ObjectOutputStream oout =
  42             new ObjectOutputStream(new ByteArrayOutputStream());
  43         List<WeakReference<?>> refs = new ArrayList<>(nreps);
  44 
  45         for (int i = 0; i < nreps; i++) {
  46             String str = new String("blargh");
  47             oout.writeObject(str);
  48             refs.add(new WeakReference<Object>(str));
  49         }
  50 
  51         oout.reset();

  52 
  53         int count = 0;
  54         for (int i=0; i<TIMES; i++) {
  55             // relying on, possibly multiple, System.gc calls to clear weak references
  56             System.gc();
  57 
  58             Iterator<WeakReference<?>> itr = refs.iterator();
  59             while(itr.hasNext()) {
  60                 WeakReference<?> ref = itr.next();
  61                 if (ref.get() == null) {
  62                     itr.remove();
  63                 }
  64             }
  65             if (refs.isEmpty())
  66                 break;
  67             Thread.sleep(20);
  68             count++;
  69             if (count % 10 == 0)
  70                 System.out.println("Looping " + count + " times");
  71         }
  72 
  73         if (!refs.isEmpty()) {
  74             throw new Error("failed to garbage collect object");





  75         }
  76     }
  77 }