java.lang.ClassNotFoundException: while accessing files from another package

I am compiling jitsi to add some changes to the project. I've implemented a few changes and the project is working fine till now. I have come to a point where I need files from this package to this one. I am trying to access VideoConfigurationPanel.java to ConfigurationFrame.java.

It imports everything successfully and doesn't show any error but while compiling and running the application, it throws the following error:

[java] Hotplug cache populated with: '\\?\intelaudio#func_01&ven_10ec&dev_0236&subsys_102808c9&rev_1000#4&1c3d4150&0&0001#{6994ad04-93ef-11d0-a3cc-00a0c9223196}\rtstereomixwave'
[java] Hotplug cache populated with: '\\?\intelaudio#func_01&ven_10ec&dev_0236&subsys_102808c9&rev_1000#4&1c3d4150&0&0001#{6994ad04-93ef-11d0-a3cc-00a0c9223196}\rtmicinsstwave'
[java] Hotplug cache populated with: '\\?\intelaudio#func_01&ven_10ec&dev_0236&subsys_102808c9&rev_1000#4&1c3d4150&0&0001#{6994ad04-93ef-11d0-a3cc-00a0c9223196}\rearlineoutwavesst'
[java] before paHostApiInitializers[0].
[java] after paHostApiInitializers[0].
[java] 2020-07-12 16:00:15.450 SEVERE: [46] util.UtilActivator.uncaughtException().122 An uncaught exception occurred in thread=Thread[AWT-EventQueue-0,6,main] and message was: net/java/sip/communicator/impl/neomedia/VideoConfigurationPanel
[java] java.lang.NoClassDefFoundError: net/java/sip/communicator/impl/neomedia/VideoConfigurationPanel
[java]     at net.java.sip.communicator.impl.gui.newui.GUITest.<init>(GUITest.java:972)
[java]     at net.java.sip.communicator.impl.gui.UIServiceImpl.loadApplicationGui(UIServiceImpl.java:165)
[java]     at net.java.sip.communicator.impl.gui.GuiActivator$1.run(GuiActivator.java:186)
[java] ERROR: Bundle net.java.sip.communicator.plugin.msofficecomm [49] Error starting reference:file:sc-bundles/plugin-msofficecomm.jar (org.osgi.framework.BundleException: Activator start error in bundle net.java.sip.communicator.plugin.msofficecomm [49].)
[java]     at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
[java]     at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
[java]     at java.awt.EventQueue.access$500(EventQueue.java:97)
[java]     at java.awt.EventQueue$3.run(EventQueue.java:709)
[java]     at java.awt.EventQueue$3.run(EventQueue.java:703)
[java]     at java.security.AccessController.doPrivileged(Native Method)
[java]     at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
[java]     at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
[java]     at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
[java]     at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
[java]     at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
[java]     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
[java]     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
[java]     at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
[java] Caused by: java.lang.ClassNotFoundException: net.java.sip.communicator.impl.neomedia.VideoConfigurationPanel not found by net.java.sip.communicator.swingui [1]
[java]     at org.apache.felix.framework.BundleWiringImpl.findClassOrResourceByDelegation(BundleWiringImpl.java:1639)
[java]     at org.apache.felix.framework.BundleWiringImpl.access$200(BundleWiringImpl.java:80)
[java]     at org.apache.felix.framework.BundleWiringImpl$BundleClassLoader.loadClass(BundleWiringImpl.java:2053)
[java]     at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
[java]     ... 17 more
[java] 2020-07-12 16:00:15.481 SEVERE: [20] plugin.msofficecomm.Messenger.<clinit>().176 Couldn't load jmsofficecomm. If you are debugging, make sure that HKLM\SOFTWARE[\Wow6432Node]\Microsoft\Office\Outlook\Call Integration\IMApplication is set to javaw.exe; unsupported JNI version 0xFFFFFFFF required by C:\Users\Jamshaid\Downloads\jitsi-5602\lib\native\windows-64\jmsofficecomm.dll
[java] java.lang.ExceptionInInitializerError
[java]     at net.java.sip.communicator.plugin.msofficecomm.MsOfficeCommActivator.start(MsOfficeCommActivator.java:72)
[java]     at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:697)
[java]     at org.apache.felix.framework.Felix.activateBundle(Felix.java:2240)
[java]     at org.apache.felix.framework.Felix.startBundle(Felix.java:2146)
[java]     at org.apache.felix.framework.Felix.setActiveStartLevel(Felix.java:1373)
[java]     at org.apache.felix.framework.FrameworkStartLevelImpl.run(FrameworkStartLevelImpl.java:308)
[java]     at java.lang.Thread.run(Thread.java:748)
[java] Caused by: java.lang.RuntimeException: java.lang.UnsatisfiedLinkError: unsupported JNI version 0xFFFFFFFF required by C:\Users\Jamshaid\Downloads\jitsi-5602\lib\native\windows-64\jmsofficecomm.dll
[java]     at net.java.sip.communicator.plugin.msofficecomm.Messenger.<clinit>(Messenger.java:180)
[java]     ... 7 more
[java] Caused by: java.lang.UnsatisfiedLinkError: unsupported JNI version 0xFFFFFFFF required by C:\Users\Jamshaid\Downloads\jitsi-5602\lib\native\windows-64\jmsofficecomm.dll
[java]     at java.lang.ClassLoader$NativeLibrary.load(Native Method)
[java]     at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1934)
[java]     at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1850)
[java]     at java.lang.Runtime.loadLibrary0(Runtime.java:870)
[java]     at java.lang.System.loadLibrary(System.java:1122)
[java]     at net.java.sip.communicator.plugin.msofficecomm.Messenger.<clinit>(Messenger.java:172)
[java]     ...

It works fine when I don't import the said file from one package to the other one. The project runs successfully but when I import the VideoConfigurationPanel to ConfigurationFrame, it throws the ClassNotFoundException. I am unable to get the cause behind it. I am running the project using cmd with ant rebuild run. Any help would be really appreciated. Thanks

Do you see this line?

Caused by: java.lang.UnsatisfiedLinkError: unsupported JNI version 0xFFFFFFFF required by C:\Users\Jamshaid\Downloads\jitsi-5602\lib\native\windows-64\jmsofficecomm.dll [java] at java.lang.ClassLoader$NativeLibrary.load(Native Method)

This means, like said in this post (unsupported JNI version 0xFFFFFFFF), that the initialization of jmsofficecomm.dll failed. Somewhere in this function (https://github.com/jitsi/jitsi/blob/848ef195b2481c67d4766c6efebb9132570acb07/src/native/windows/msofficecomm/OutOfProcessServer.cxx#L222) , isMicrosoftOfficeOutlookCallIntegrationIMApplication() is failing. I can't make much sense from this code, but I would recommend looking into the registry at: SOFTWARE\Microsoft\Office\Outlook\Call Integration .(https://github.com/jitsi/jitsi/blob/848ef195b2481c67d4766c6efebb9132570acb07/src/native/windows/msofficecomm/OutOfProcessServer.cxx#L117)