thank you for the reply and time you spend. your guest domain should not be running and then run my program without any change.you will see an exception where you dont expect it to occur. libvirt : 0.6.3 and libvirt-java: 0.4.2 i am using. Please let me know if i miss to provide you any other details. <div class="gmail_quote">On Fri, Sep 3, 2010 at 3:29 AM, Matthias Bolte <<a href="mailto:matthias.bolte@googlemail.com">matthias.bolte@googlemail.com</a>> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> 2010/9/2 Ravi Pawar <<a href="mailto:ravifc@gmail.com">ravifc@gmail.com</a>>: <div class="im">> please check the java file attached they throws the exception in case of > passing. > please let me know if i am missing something. > </div>Can you explain in more detail what one should do to reproduce the problem you seem to see with the attached code? Also you didn't mention which versions of libvirt and libvirt-java you're using. When I run you example code (with a guest name that exists in my setup and libvirt and libvirt-java form current git head) I don't see any exceptions. Even when I add e.printStackTrace() to the catch block of TestMultiThreadingLibvirtWithError I don't see exceptions. $ java -classpath ./target/libvirt-0.4.6.jar:./ravi:/usr/share/java/jna.jar Test start class 0 start class 1 start class 2 start class 3 start class 4 start class 5 start class 6 start class 7 start class 8 start class 9 So this works for me. Matthias </blockquote></div> -- Thanks & Regards Ravi Pawar