java.util.ConcurrentModificationException

Classic Servoy
1

got a few of those today;

anyone know what causes this?

2

i know what causes those and those are bugs. They shouldn’t happen
Please send over the stacktraces you see when it happens.

3

We are experiencing it too but it is intermittent.

2011-10-31 17:08:44,323 ERROR [AWT-EventQueue-0] com.servoy.j2db.util.Debug - Throwable
org.mozilla.javascript.WrappedException: Wrapped java.util.ConcurrentModificationException (C:\Development\team servers\Servoy_6_Rogel\workspace-blockuser\commons\forms\base_transaction.js#237)
	at org.mozilla.javascript.Context.throwAsScriptRuntimeEx(Context.java:1828)
	at org.mozilla.javascript.MemberBox.invoke(MemberBox.java:199)
	at org.mozilla.javascript.NativeJavaMethod.call(NativeJavaMethod.java:367)
	at org.mozilla.javascript.Interpreter.interpretLoop(Interpreter.java:3666)
	at script.saveEditedRecordsInWindow(C:\Development\team servers\Servoy_6_Rogel\workspace-blockuser\commons\forms\base_transaction.js:237)
	at script.saveEdits(C:\Development\team servers\Servoy_6_Rogel\workspace-blockuser\commons\forms\base_transaction.js:206)
	at org.mozilla.javascript.Interpreter.interpret(Interpreter.java:2680)
	at org.mozilla.javascript.InterpretedFunction.call(InterpretedFunction.java:166)
	at org.mozilla.javascript.ContextFactory.doTopCall(ContextFactory.java:387)
	at org.mozilla.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3134)
	at org.mozilla.javascript.InterpretedFunction.call(InterpretedFunction.java:165)
	at com.servoy.j2db.scripting.ScriptEngine.executeFunction(ScriptEngine.java:523)
	at com.servoy.j2db.debug.RemoteDebugScriptEngine.executeFunction(RemoteDebugScriptEngine.java:379)
	at com.servoy.j2db.FormController.executeFunction(FormController.java:4057)
	at com.servoy.j2db.FormController.executeFunction(FormController.java:3936)
	at com.servoy.j2db.FormController.executeFunction(FormController.java:3858)
	at com.servoy.j2db.FormController$ScriptExecuter.executeFunction(FormController.java:3713)
	at com.servoy.j2db.ui.BaseEventExecutor.fireEventCommand(BaseEventExecutor.java:271)
	at com.servoy.j2db.ui.BaseEventExecutor.fireActionCommand(BaseEventExecutor.java:217)
	at com.servoy.j2db.ui.BaseEventExecutor.fireActionCommand(BaseEventExecutor.java:212)
	at com.servoy.j2db.smart.dataui.AbstractScriptButton$2.actionPerformed(AbstractScriptButton.java:660)
	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
	at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
	at java.awt.Component.processMouseEvent(Unknown Source)
	at javax.swing.JComponent.processMouseEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$000(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextEntry(Unknown Source)
	at java.util.HashMap$KeyIterator.next(Unknown Source)
	at sun.reflect.GeneratedMethodAccessor951.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.mozilla.javascript.MemberBox.invoke(MemberBox.java:179)
	... 54 more
4

that one i can’t explain
That one is inside java itself, inside code that is even generated by java.
so this looks like a java bug to me, i guess this is not reproducible at all?

5

jcompagner:
that one i can’t explain
That one is inside java itself, inside code that is even generated by java.
so this looks like a java bug to me, i guess this is not reproducible at all?

Yup. Has something to do with HashMaps. Thanks Johan! The exception is intermittent.