500 Internal Server Error

org.hibernate.exception.GenericJDBCException: Cannot open connection
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:91)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:79)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:29)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:307)
at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:109)
at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:105)
at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1561)
at org.hibernate.loader.Loader.doQuery(Loader.java:661)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:223)
at org.hibernate.loader.Loader.loadEntity(Loader.java:1782)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:93)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:81)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:2729)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:365)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:346)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:123)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:82)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:809)
at org.hibernate.impl.SessionImpl.immediateLoad(SessionImpl.java:771)
at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:62)
at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:98)
at org.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:133)
at instore.content.model.LocaleSet$$EnhancerByCGLIB$$3a691020.getDefault(<generated>)
at instore.content.LocaleSetView.getDefaultLocale(LocaleSetView.java:47)
at instore.content.CategoryView.getDefaultLocale(CategoryView.java:1079)
at instore.content.RepositoryView.createAtNode(RepositoryView.java:180)
at instore.content.view.Site.getSite(Site.java:65)
at instore.content.view.struts.NavigateAction.execute(NavigateAction.java:52)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.ResourceFilterChain.doFilter(ResourceFilterChain.java:65)
at oracle.security.jazn.oc4j.JAZNFilter.doFilter(Unknown Source)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.EvermindFilterChain.doFilter(EvermindFilterChain.java:16)
at instore.hibernate.HibernateSessionFilter.doFilter(HibernateSessionFilter.java:24)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.EvermindFilterChain.doFilter(EvermindFilterChain.java:20)
at instore.waf.utils.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:170)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java:659)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java:330)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java:830)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.AJPRequestHandler.run(AJPRequestHandler.java:224)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].server.http.AJPRequestHandler.run(AJPRequestHandler.java:133)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].util.ReleasableResourcePooledExecutor$MyWorker.run(ReleasableResourcePooledExecutor.java:192)
at java.lang.Thread.run(Thread.java:534)
Caused by: java.sql.SQLException: Io exception: The Network Adapter could not establish the connection
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:137)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:174)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:286)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:327)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:433)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:150)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:31)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:571)
at com.evermind[Oracle Application Server Containers for J2EE 10g (10.1.2.0.2)].sql.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:160)
at org.hibernate.connection.DatasourceConnectionProvider.getConnection(DatasourceConnectionProvider.java:69)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:304)
... 43 more