Software problems - 'locking assertion failure'

Hi,
I've been trying to install the reprap host software on ubuntu.
I have just finished the third try, with no success.

When I try to run the software, I get a screen dump (see below), including 'locking assertion failure'. a window appears telling me my serial cable is not connected. when i click ok it goes back to a command prompt. I'm wondering if i have conflicting versions of java, here is the contents of my jvm folder:


root@ralph-laptop:/usr/lib/jvm# ls
java-1.5.0-sun java-1.5.0-sun-1.5.0.15 java-6-sun-1.6.0.06


Before the third install attempt I went into the package manager and removed anything with sun-java in the name, so i would expect to see only one in there.

Anyone got any bright ideas? I'm at a loss.

Thanks

Ralph


Heres the screen dump:


root@ralph-laptop:/home/ralph/reprap-host-20080523# ./reprap-host.sh
Locking assertion failure. Backtrace:
#0 /usr/lib/libxcb-xlib.so.0 [0xb7f1a767]
#1 /usr/lib/libxcb-xlib.so.0(xcb_xlib_unlock+0x31) [0xb7f1a8b1]
#2 /usr/lib/libX11.so.6(_XReply+0xfd) [0xb16921bd]
#3 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so [0xb1782dce]
#4 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so [0xb176cd77]
#5 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so [0xb176cef3]
#6 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so(Java_sun_awt_X11GraphicsEnvironment_initDisplay+0x26) [0xb176d136]
#7 [0xb25c9bfa]
#8 [0xb25c3b3b]
#9 [0xb25c3b3b]
#10 [0xb25c1219]
#11 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so [0xb77812bc]
#12 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so [0xb7895ed8]
#13 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so [0xb77810ef]
#14 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so(JVM_DoPrivileged+0x32d) [0xb77deb9d]
#15 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/libjava.so(Java_java_security_AccessController_doPrivileged__Ljava_security_PrivilegedAction_2+0x3d) [0xb757530d]
#16 [0xb25c94ab]
#17 [0xb25c3a64]
#18 [0xb25c1219]
#19 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so [0xb77812bc]
Locking assertion failure. Backtrace:
#0 /usr/lib/libxcb-xlib.so.0 [0xb7f1a767]
#1 /usr/lib/libxcb-xlib.so.0(xcb_xlib_lock+0x2e) [0xb7f1a81e]
#2 /usr/lib/libX11.so.6 [0xb1691518]
#3 /usr/lib/libX11.so.6(XGetVisualInfo+0x26) [0xb16880a6]
#4 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so [0xb176c0b9]
#5 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so [0xb176c303]
#6 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so [0xb176cfa1]
#7 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/xawt/libmawt.so(Java_sun_awt_X11GraphicsEnvironment_initDisplay+0x26) [0xb176d136]
#8 [0xb25c9bfa]
#9 [0xb25c3b3b]
#10 [0xb25c3b3b]
#11 [0xb25c1219]
#12 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so [0xb77812bc]
#13 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so [0xb7895ed8]
#14 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so [0xb77810ef]
#15 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/client/libjvm.so(JVM_DoPrivileged+0x32d) [0xb77deb9d]
#16 /usr/lib/jvm/java-1.5.0-sun-1.5.0.15/jre/lib/i386/libjava.so(Java_java_security_AccessController_doPrivileged__Ljava_security_PrivilegedAction_2+0x3d) [0xb757530d]
#17 [0xb25c94ab]
#18 [0xb25c3a64]
#19 [0xb25c1219]
Experimental: JNI_OnLoad called.
Stable Library
=========================================
Native lib Version = RXTX-2.1-7
Java lib Version = RXTX-2.1-7
java.lang.Exception:
Could not connect at /dev/ttyS0.

Check to make sure that is the right path.
Check that you have your serial connector plugged in.The program will continue but your geometry preference has been set to 'nullcartesian' for this session.
at org.reprap.Main.initComms(Unknown Source)
at org.reprap.Main.access$2200(Unknown Source)
at org.reprap.Main$22.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: javax/swing/GroupLayout$Group
at org.reprap.Main$22.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
root@ralph-laptop:/home/ralph/reprap-host-20080523#


From another thread with the same errors:

"1. From [bugs.launchpad.net] this is a bug in the Ubuntu hardy distro's packaged xorg/libsdl which can be fixed in this case by doing the following:
sudo sed -i 's/XINERAMA/FAKEEXTN/g' /usr/lib/jvm/java-1.5.0-sun/jre/lib/i386/xawt/libmawt.so

2. The exception in swing is because its Java 1.6 specific."

So try the first fix and see if most of the errors go away. Then you're just left with the problem that you don't seem to be using the Java 1.6 JRE that you obviously have. Have a look at [reprap.org] for commands to list and change which JRE you're using.

Alternatively, according to a blog entry by Adrian [blog.reprap.org] it will also work under 1.5 if you have the swing-layout-1.0.3.jar in your classpath which you can download from [mirrors.ibiblio.org]. I haven't tried this and you will probably need to get the host software from the svn tree rather than the prepackaged zip file on sourceforge (see [reprap.org])

Hope all that helps.

success! thanks a lot.
i tried that first fix, it removed some of the errors (the locking assertion bit) but it still wouldnt run.
i downloaded and reinstalled the sun-java-6 jdk and did
$ update-java-alternatives --set java-6-sun
and went through the procedure from the installation instructions again, and now it seems happy.
thank you!
ralph