53         HashMap<String, Long> numInstancesOfClass = new HashMap<String, Long>();
54         HashMap<String, Long> sizeOfInstances = new HashMap<String, Long>();
55 
56         for (RecordedEvent event : objectCountEvents) {
57             String className = Events.assertField(event, "objectClass.name").notEmpty().getValue();
58             long count = Events.assertField(event, "count").atLeast(0L).getValue();
59             long totalSize = Events.assertField(event, "totalSize").atLeast(1L).getValue();
60             System.out.println(className);
61             numInstancesOfClass.put(className, count);
62             sizeOfInstances.put(className, totalSize);
63         }
64         System.out.println(numInstancesOfClass);
65         final String fooArrayName = "[Ljdk/jfr/event/gc/objectcount/Foo;";
66         Asserts.assertTrue(numInstancesOfClass.containsKey(fooArrayName), "Expected an event for the Foo array");
67         Asserts.assertEquals(sizeOfInstances.get(fooArrayName), expectedFooArraySize(Constants.oneMB), "Wrong size of the Foo array");
68     }
69 
70     private static long expectedFooArraySize(long count) {
71         boolean runsOn32Bit = System.getProperty("sun.arch.data.model").equals("32");
72         int bytesPerWord = runsOn32Bit ? 4 : 8;
73         int objectHeaderSize = bytesPerWord * 3; // length will be aligned on 64 bits

74         int alignmentInOopArray = runsOn32Bit ? 4 : 0;
75         int ptrSize = bytesPerWord;
76         return objectHeaderSize + alignmentInOopArray + count * ptrSize;
77     }
78 }

53         HashMap<String, Long> numInstancesOfClass = new HashMap<String, Long>();
54         HashMap<String, Long> sizeOfInstances = new HashMap<String, Long>();
55 
56         for (RecordedEvent event : objectCountEvents) {
57             String className = Events.assertField(event, "objectClass.name").notEmpty().getValue();
58             long count = Events.assertField(event, "count").atLeast(0L).getValue();
59             long totalSize = Events.assertField(event, "totalSize").atLeast(1L).getValue();
60             System.out.println(className);
61             numInstancesOfClass.put(className, count);
62             sizeOfInstances.put(className, totalSize);
63         }
64         System.out.println(numInstancesOfClass);
65         final String fooArrayName = "[Ljdk/jfr/event/gc/objectcount/Foo;";
66         Asserts.assertTrue(numInstancesOfClass.containsKey(fooArrayName), "Expected an event for the Foo array");
67         Asserts.assertEquals(sizeOfInstances.get(fooArrayName), expectedFooArraySize(Constants.oneMB), "Wrong size of the Foo array");
68     }
69 
70     private static long expectedFooArraySize(long count) {
71         boolean runsOn32Bit = System.getProperty("sun.arch.data.model").equals("32");
72         int bytesPerWord = runsOn32Bit ? 4 : 8;
73         // length will be in klass-gap on 64 bits, extra field on 32 bits.
74         int objectHeaderSize = bytesPerWord * (runsOn32Bit ? 3 : 2);
75         int alignmentInOopArray = runsOn32Bit ? 4 : 0;
76         int ptrSize = bytesPerWord;
77         return objectHeaderSize + alignmentInOopArray + count * ptrSize;
78     }
79 }