Chciałbym serializować obiekt który zawiera listę. Lista ta powstała za pomocą hibernate z istniejącej tabeli w MySQL. Bez listy serializacja wykonuje się pomyślnie. Obiekt przesyłany jest z Serwera na Socket.
tak przygotowuję listę do serializacji w klasie Users
List users_list = new HibernateExample().displayUsers(); //metoda przygotowuje listę i zwraca ją
od strony Socketa takie mam błędy:
java.io.EOFException
at java.io.ObjectInputStream$BlockDataInputStream.peekByte(Unknown Source)
at java.io.ObjectInputStream.readObject0(Unknown Source)
at java.io.ObjectInputStream.readObject(Unknown Source)
at EchoClient.showUsers(EchoClient.java:38)
at Main.main(Main.java:12)
od strony Servera takie mam błędy:
.
.
.
Oct 23, 2011 12:45:38 PM org.hibernate.impl.SessionFactoryImpl <init>
INFO: building session factory
Initial SessionFactory creation failed.org.hibernate.InstantiationException: could not instantiate test objectUsers
Exception in thread "main" java.lang.ExceptionInInitializerError
at HibernateUtil.<clinit>(HibernateUtil.java:13)
at HibernateExample.displayUsers(HibernateExample.java:11)
at Users.<init>(Users.java:12)
at Server.showUsers(Server.java:55)
at Main.main(Main.java:20)
Caused by: org.hibernate.InstantiationException: could not instantiate test objectUsers
at org.hibernate.engine.UnsavedValueFactory.instantiate(UnsavedValueFactory.java:25)
at org.hibernate.engine.UnsavedValueFactory.getUnsavedIdentifierValue(UnsavedValueFactory.java:44)
at org.hibernate.tuple.PropertyFactory.buildIdentifierProperty(PropertyFactory.java:44)
at org.hibernate.tuple.entity.EntityMetamodel.<init>(EntityMetamodel.java:123)
at org.hibernate.persister.entity.AbstractEntityPersister.<init>(AbstractEntityPersister.java:434)
at org.hibernate.persister.entity.SingleTableEntityPersister.<init>(SingleTableEntityPersister.java:109)
at org.hibernate.persister.PersisterFactory.createClassPersister(PersisterFactory.java:55)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:226)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1294)
at HibernateUtil.<clinit>(HibernateUtil.java:10)
... 4 more
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:532)
at org.hibernate.engine.UnsavedValueFactory.instantiate(UnsavedValueFactory.java:22)
... 13 more
Caused by: java.lang.NullPointerException
at HibernateExample.displayUsers(HibernateExample.java:14)
at Users.<init>(Users.java:12)
... 18 more