RFR: 8259008: ArithmeticException was thrown at "Monitor Cache Dump" on HSDB [v6]

[David Holmes]

On Wed, 27 Jan 2021 00:59:59 GMT, Yasumasa Suenaga <ysuenaga at openjdk.org> wrote:

>> I saw the exception as following when I chose "Monitor Cache Dump" menu on HSDB:
>> 
>> Exception in thread "AWT-EventQueue-0" java.lang.ExceptionInInitializerError
>>         at jdk.hotspot.agent/sun.jvm.hotspot.ui.MonitorCacheDumpPanel.dumpOn(MonitorCacheDumpPanel.java:92)
>>         at jdk.hotspot.agent/sun.jvm.hotspot.ui.MonitorCacheDumpPanel.<init>(MonitorCacheDumpPanel.java:59)
>>         at jdk.hotspot.agent/sun.jvm.hotspot.HSDB.showMonitorCacheDumpPanel(HSDB.java:1556)
>>         at jdk.hotspot.agent/sun.jvm.hotspot.HSDB$16.actionPerformed(HSDB.java:338)
>>         at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972)
>>         at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2313)
>>         at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405)
>>         at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
>>         at java.desktop/javax.swing.AbstractButton.doClick(AbstractButton.java:374)
>>         at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1022)
>>         at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1066)
>>         at java.desktop/java.awt.Component.processMouseEvent(Component.java:6617)
>>         at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3342)
>>         at java.desktop/java.awt.Component.processEvent(Component.java:6382)
>>         at java.desktop/java.awt.Container.processEvent(Container.java:2264)
>>         at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4993)
>>         at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2322)
>>         at java.desktop/java.awt.Component.dispatchEvent(Component.java:4825)
>>         at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4934)
>>         at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4563)
>>         at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4504)
>>         at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2308)
>>         at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2773)
>>         at java.desktop/java.awt.Component.dispatchEvent(Component.java:4825)
>>         at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:772)
>>         at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
>>         at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
>>         at java.base/java.security.AccessController.doPrivileged(AccessController.java:391)
>>         at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
>>         at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:95)
>>         at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
>>         at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:743)
>>         at java.base/java.security.AccessController.doPrivileged(AccessController.java:391)
>>         at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
>>         at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742)
>>         at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
>>         at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
>>         at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
>>         at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
>>         at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
>>         at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
>> Caused by: java.lang.ArithmeticException: / by zero
>>         at jdk.hotspot.agent/sun.jvm.hotspot.runtime.ObjectSynchronizer.initialize(ObjectSynchronizer.java:55)
>>         at jdk.hotspot.agent/sun.jvm.hotspot.runtime.ObjectSynchronizer$1.update(ObjectSynchronizer.java:40)
>>         at jdk.hotspot.agent/sun.jvm.hotspot.runtime.VM.registerVMInitializedObserver(VM.java:578)
>>         at jdk.hotspot.agent/sun.jvm.hotspot.runtime.ObjectSynchronizer.<clinit>(ObjectSynchronizer.java:38)
>>         ... 41 more
>> 
>> This exception seems to be caused by [JDK-8253064](https://bugs.openjdk.java.net/browse/JDK-8253064). It has changed `ObjectSynchronizer`, but it has not changed SA code.
>
> Yasumasa Suenaga has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update testcase

Hi Yasumasa,

I thought the comments regarding the test were to use an if statement to check iter.hasNext() and return after seeing one Monitor, rather than keeping the while-loop and reporting every single Monitor found. The latter seems a waste of timer as we don't know how many Monitors to expect, so it adds no value to report them all.

Cheers,
David

-------------

PR: https://git.openjdk.java.net/jdk/pull/1910