Invalid memory access of location 0x20 eip=0x

[steve labarbera]

I have an issue on a mac where the application crashes with the error "Invalid
memory access of location 0x20 eip=0x95b3ced."

I ran a search and found a few bugs in SWT a while back that caused this but
appear to be fixed now. It said to fix by calling -XstartOnFirstThread

I added the following to my command-line startup: -d32 -XstartOnFirstThread

You think it might be due to me creating a thread in between those mandatory
method calls?

public static void main(String args)
{
UIUtils.setPreferredLookAndFeel();
NativeInterface.open();
Thread t = new Thread(){
public void run()
{
StartBurp.main(new String{""});
}
};
t.start();
//44StartBurp.main(new String{""});

NativeInterface.runEventPump();

}

This crashes pretty much every time I load JWebBrowser.

I do get this error when I first click on the JWebBrowser tab:

java.lang.NullPointerException
at org.eclipse.swt.widgets.Shell.setEnabled(Unknown Source)
at chrriis.dj.nativeswing.swtimpl.core.SWTNativeComponent$CMN_setShellEnabled.
run(SWTNativeComponent.java:1144)
at chrriis.dj.nativeswing.swtimpl.CommandMessage.runCommand(CommandMessage.jav
a:61)
at chrriis.dj.nativeswing.swtimpl.core.ControlCommandMessage.runCommand(Contro
lCommandMessage.java:166)
at chrriis.dj.nativeswing.swtimpl.NativeInterface.runMessageCommand(NativeInte
rface.java:168)
at chrriis.dj.nativeswing.swtimpl.core.SWTNativeInterface.runMessageCommand(SW
TNativeInterface.java:1315)
at chrriis.dj.nativeswing.swtimpl.core.MessagingInterface.runMessage(Messaging
Interface.java:121)
at chrriis.dj.nativeswing.swtimpl.core.MessagingInterface.processReceivedMessa
ges(MessagingInterface.java:106)
at chrriis.dj.nativeswing.swtimpl.core.MessagingInterface.access$2(MessagingIn
terface.java:94)
at chrriis.dj.nativeswing.swtimpl.core.MessagingInterface$2$2.run(MessagingInt
erface.java:438)
at org.eclipse.swt.widgets.RunnableLock.run(Unknown Source)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Unknown Source)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at chrriis.dj.nativeswing.swtimpl.core.SWTNativeInterface$InProcess.runSWTEven
tPump(SWTNativeInterface.java:667)
at chrriis.dj.nativeswing.swtimpl.core.SWTNativeInterface$InProcess.runEventPu
mp(SWTNativeInterface.java:659)
at chrriis.dj.nativeswing.swtimpl.core.SWTNativeInterface.runEventPump_(SWTNat
iveInterface.java:475)
at chrriis.dj.nativeswing.swtimpl.NativeInterface.runEventPump(NativeInterface
.java:124)
at penatrator.unittests.SiteMapsTester.main(SiteMapsTester.java:33)

[Christopher Deckers]

Hi,

Are you manipulating certain components outside the UI thread?

Cheers,
-Christopher

[steve labarbera]

honestly not sure. Everything is being done within classes inside that one
thread in main does everything need to be done inside a SwingWorker thread? Im
going into work tomorrow i'll play around with it a bit. But yeah it was
crashing a bunch. In windows using same code its running like a charm. just
was not sure if i was doing something incorrectly. Can i assume since in
windows it runs fine its not the manipulation of components outside the UI
thread.

What be easiest way to see if its the issue you think may be causing the
issue?

[Christopher Deckers]

Can i assume since in windows it runs fine its not the manipulation of
components outside the UI thread.

I would assume so, but there is no 100% guarantee: native components can
behave differently on different platforms because of their native nature.

What be easiest way to see if its the issue you think may be causing the
issue?

I am not sure, but if you happen to have a simple standalone test case, please
e-mail it to me ( chrriis (at) nextencia (dot net ) so that I have a look and
fix bugs if I find any.

-Christopher

[adrayb]

Hello TyWeed420,

Did you ever get this issue resolved ? I am seeing the same problem.

[Christopher Deckers]

java.lang.NullPointerException
at org.eclipse.swt.widgets.Shell.setEnabled(Unknown Source)

This error is caused by this SWT bug:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=344401

I strongly suggest anyone affected by this bug to vote on it. Also indicate
that the fact you are using a library that is hitting this bug is a
showstopper for you (no possibility to change the library code, etc.)

Hope this helps,
-Christopher