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13  * accompanied this code).
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23 
24 /*
25  * @test
26  * @summary Verifies the behaviour of Unsafe.allocateInstance
27  * @library /test/lib
28  * @modules java.base/jdk.internal.misc
29  *          java.management
30  * @run main AllocateInstance
31  */
32 
33 import jdk.internal.misc.Unsafe;
34 import static jdk.test.lib.Asserts.*;
35 
36 public class AllocateInstance {
37     static final Unsafe UNSAFE = Unsafe.getUnsafe();
38 
39     class TestClass {
40         public boolean calledConstructor = false;
41 
TestClass()42         public TestClass() {
43             calledConstructor = true;
44         }
45     }
46 
testConstructorCall()47     static void testConstructorCall() throws InstantiationException {
48         // allocateInstance() should not result in a call to the constructor
49         TestClass tc = (TestClass)UNSAFE.allocateInstance(TestClass.class);
50         assertFalse(tc.calledConstructor);
51     }
52 
53     abstract class AbstractClass {
AbstractClass()54         public AbstractClass() {}
55     }
56 
testAbstractClass()57     static void testAbstractClass() {
58         try {
59             AbstractClass ac = (AbstractClass) UNSAFE.allocateInstance(AbstractClass.class);
60             throw new AssertionError("Should throw InstantiationException for an abstract class");
61         } catch (InstantiationException e) {
62             // Expected
63         }
64     }
65 
66     interface AnInterface {}
67 
testInterface()68     static void testInterface() {
69         try {
70             AnInterface ai = (AnInterface) UNSAFE.allocateInstance(AnInterface.class);
71             throw new AssertionError("Should throw InstantiationException for an interface");
72         } catch (InstantiationException e) {
73             // Expected
74         }
75     }
76 
main(String args[])77     public static void main(String args[]) throws Exception {
78         for (int i = 0; i < 20_000; i++) {
79             testConstructorCall();
80             testAbstractClass();
81             testInterface();
82         }
83     }
84 }
85