Solved: java.lang.NoClassDefFoundError: Could not initialize class

jvw1954's picture

I have problems with contacting the GPS with BT747 2.1.3 on my Eee PC with Debian 7 and Open-JDK-7.

/opt/BT747_2.1.3/opt/BT747_2.1.3/run_j2se.sh164751 - Classgps.connection.GPSRxTxPort
Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: Could not initialize class
at gps.connection.GPSRxTxPort.openPort(Unknown Source)
at gps.connection.GPSrxtx.myOpenPort(Unknown Source)
at gps.connection.GPSrxtx.setFreeTextPortAndOpen(Unknown Source)
at bt747.model.Controller.openFreeTextPort(Unknown Source)
at bt747.j2se_view.BT747Main.access$300$6e36da35(Unknown Source)
at bt747.j2se_view.BT747Main$7.actionPerformed(Unknown Source)

At home on my desktop PC with Debian8 everything runs fine.

How could I solve this?

jvw1954's picture

With OpenJDK 6 I have the

With OpenJDK 6 I have the same problems.

jvw1954's picture

After purging ' librxtx-java'

After purging ' librxtx-java' ' bt747' works fine!

mdeweerd's picture

Hi Thanks for keeping us


Thanks for keeping us updated - I did not see the message before.

Did you have to remove the librtx-java from the system or from bt747?

As far as I remember the script configures for the system's rxtx in priority and it's a bit strange that the system's version would be incorrect.


uname -aLinux xubuntu

uname -a
Linux xubuntu 4.8.0-22-generic #24-Ubuntu SMP Sat Oct 8 09:15:00 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Holux m241

1205 - BT747 2.X.2013 Build:BT747_mdeweerd.2013.20150903012403962
1206 - Initial: 1180x575  Screen: 1920x1080 Final: 1180x575
1206 - Linux
1206 - amd64
1206 - 4.8.0-22-generic
1206 - 1.8.0_112
1206 - 64

6097 - Classgps.connection.GPSRxTxPort
WARNING:  RXTX Version mismatch
        Jar version = RXTX-2.2pre1
        native lib Version = RXTX-2.2pre2
6134 - Port opened
6135 - Attempting saving settings to /home/xubuntu/BT747SettingsJ2SE.pdb
6136 - Writing settings success for /home/xubuntu/BT747SettingsJ2SE.pdb
23067 - >PMTK604 true
23098 - >PMTK182,2,9,9F true
Opened file /home/xubuntu/gpsRawDebug.txt in mode 4 rw
Opened file /home/xubuntu/gpsRawDebug.txt in mode 3 rw
Timeout: 27108-23098>4000
27108 - No ack:PMTK182,2,12
27108 - No ack:PMTK605
27108 - No ack:PMTK604
27108 - No ack:PMTK182,2,9,9F
27108 - >PMTK430 true
27140 - >HOLUX241,5 true
27172 - >PMTK490 true
27204 - >PMTK414 true
Timeout: 31211-27204>4000
31211 - No ack:PMTK430
31211 - No ack:HOLUX241,5
31211 - No ack:PMTK490
31212 - No ack:PMTK414
31212 - >PMTK182,2,6 true
31243 - >PMTK182,2,3 true
31275 - >PMTK182,2,5 true

And Still NOT working at all. Nothing. Holux does even freeze.

gpsbabel can read the log just fine. but can not set extended Tracking like VDOP, NSAT

What am I missing after 8 hours trying to find ANY usefull hints.... ??? (Obviously nothing helped yet) :-((((((((

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