Tomcat Java.io.NotSerializableException Error Resolution method

Run the project under Tomcat, start, open a page (let session function), stop, and then start, it is possible to report errors similar to the following: Java.io.NotSerializableException
The reason for this is that when Tomcat stops, the session resource is saved, and then when the service is restarted, it attempts to resume sessions.

Solution One:
Configure Tomcat does not save session resources when it is off.
In the Server.xml context, add the following:
<manager classname= "Org.apache.catalina.session.PersistentManager" saveonrestart= "false" >
<store classname= "Org.apache.catalina.session.FileStore"/>
</Manager>

Solution Two:
Serialize the classes that need to be placed in session.
That is, let entity class Implement interface java.io.Serializable can.