exception thrown when try to run explorer again?

hello , when i try to launch explorer.jar i got this error:

/Users/apple/Downloads/objectdb-2.4.2_02/bin
KadirBASOL:bin apple$ java -jar explorer.jar
Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: javax/jdo/JDODataStoreException
at com.objectdb.Explorer$1.run(Explorer.java:56)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:701)
at java.awt.EventQueue.access$000(EventQueue.java:102)
at java.awt.EventQueue$3.run(EventQueue.java:662)
at java.awt.EventQueue$3.run(EventQueue.java:660)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:671)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:244)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:147)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:139)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:97)
Caused by: java.lang.ClassNotFoundException: javax.jdo.JDODataStoreException
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
... 15 more
KadirBASOL:bin apple$

explorer.jar cannot work without objectdb.jar, and the error indicates that objectdb.jar is not available in the classpath.

There is no objectdb.jar , only objectdb-ee.jar i saw.

I renamed objectdb-ee.jar to objectdb.jar

This time i got this error:

KadirBASOL:bin apple$ bash explorer.sh

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: javax/persistence/EntityManager
at com.objectdb.o.CRC.<init>(CRC.java:65)
at com.objectdb.o.MFR.<init>(MFR.java:66)
at com.objectdb.o.EXA.<init>(EXA.java:72)
at com.objectdb.Explorer$1.run(Explorer.java:56)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:701)
at java.awt.EventQueue.access$000(EventQueue.java:102)
at java.awt.EventQueue$3.run(EventQueue.java:662)
at java.awt.EventQueue$3.run(EventQueue.java:660)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:671)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:244)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:147)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:139)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:97)
Caused by: java.lang.ClassNotFoundException: javax.persistence.EntityManager
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
... 18 more
KadirBASOL:bin apple$

What exactly do you mean by there is no objectdb.jar?

Download the last version of ObjectDB and run the Explorer in the bin directory, which should contain objectdb.jar.