help me to resolve this error. what is it mean? how can i resolve it. it says java.lang.ClassNotFoundException: com.oracle.handson.Employees but it has been created already.
(Wrapped: Missing or inaccessible constructor "com.tangosol.coherence.jpa.JpaCacheStore(String,String,String)"
<class-scheme>
<class-name>com.tangosol.coherence.jpa.JpaCacheStore</class-name>
<init-params>
<!--
This param is the entity name
This param is the fully qualified entity class
This param should match the value of the
persistence unit name in persistence.xml
-->
<init-param>
<param-type>java.lang.String</param-type>
<param-value>Employees</param-value>
</init-param>
<init-param>
<param-type>java.lang.String</param-type>
<param-value>com.oracle.handson.Employees</param-value>
</init-param>
<init-param>
<param-type>java.lang.String</param-type>
<param-value>JPA</param-value>
</init-param>
</init-params>
</class-scheme>) java.lang.reflect.InvocationTargetException
at com.tangosol.util.Base.ensureRuntimeException(Base.java:293)
at com.tangosol.run.xml.XmlHelper.createInstance(XmlHelper.java:2542)
at com.tangosol.run.xml.XmlHelper.createInstance(XmlHelper.java:2426)
at com.tangosol.net.DefaultConfigurableCacheFactory.instantiateAny(DefaultConfigurableCacheFactory.java:3256)
at com.tangosol.net.DefaultConfigurableCacheFactory.instantiateCacheStore(DefaultConfigurableCacheFactory.java:3106)
at com.tangosol.net.DefaultConfigurableCacheFactory.instantiateReadWriteBackingMap(DefaultConfigurableCacheFactory.java:1674)
at com.tangosol.net.DefaultConfigurableCacheFactory.configureBackingMap(DefaultConfigurableCacheFactory.java:1429)
at com.tangosol.net.DefaultConfigurableCacheFactory$Manager.instantiateBackingMap(DefaultConfigurableCacheFactory.java:3904)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.partitionedService.PartitionedCache$Storage.instantiateResourceMap(PartitionedCache.CDB:22)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.partitionedService.PartitionedCache$Storage.setCacheName(PartitionedCache.CDB:25)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.partitionedService.PartitionedCache$ServiceConfig$ConfigListener.entryInserted(PartitionedCache.CDB:17)
at com.tangosol.util.MapEvent.dispatch(MapEvent.java:266)
at com.tangosol.util.MapEvent.dispatch(MapEvent.java:226)
at com.tangosol.util.MapListenerSupport.fireEvent(MapListenerSupport.java:556)
at com.tangosol.util.ObservableHashMap.dispatchEvent(ObservableHashMap.java:229)
at com.tangosol.util.ObservableHashMap$Entry.onAdd(ObservableHashMap.java:270)
at com.tangosol.util.SafeHashMap.put(SafeHashMap.java:244)
at com.tangosol.coherence.component.util.ServiceConfig$Map.put(ServiceConfig.CDB:43)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.partitionedService.PartitionedCache$StorageIdRequest.onReceived(PartitionedCache.CDB:45)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.onMessage(Grid.CDB:11)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.onNotify(Grid.CDB:33)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.PartitionedService.onNotify(PartitionedService.CDB:3)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.partitionedService.PartitionedCache.onNotify(PartitionedCache.CDB:3)
at com.tangosol.coherence.component.util.Daemon.run(Daemon.CDB:42)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.tangosol.util.ClassHelper.newInstance(ClassHelper.java:662)
at com.tangosol.run.xml.XmlHelper.createInstance(XmlHelper.java:2501)
... 23 more
Caused by: (Wrapped: Class com.oracle.handson.Employees could not be loaded) java.lang.ClassNotFoundException: com.oracle.handson.Employees
at com.tangosol.util.Base.ensureRuntimeException(Base.java:293)
at com.tangosol.coherence.jpa.JpaCacheLoader.initialize(JpaCacheLoader.java:147)
at com.tangosol.coherence.jpa.JpaCacheLoader.<init>(JpaCacheLoader.java:49)
at com.tangosol.coherence.jpa.JpaCacheStore.<init>(JpaCacheStore.java:44)
... 29 more
Caused by: java.lang.ClassNotFoundException: com.oracle.handson.Employees
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at com.tangosol.coherence.jpa.JpaCacheLoader.initialize(JpaCacheLoader.java:143)
... 31 more
Exception in thread "main" java.lang.NullPointerException
at com.handson.oracle.RunEmployeeExample.main(RunEmployeeExample.java:22)
thanks in advance