java.io.NotSerializableException: sessions.SessionLoader

Question

I created a java class to handle sessions the was created in the class annotated @WebFilter

public class SessionLoader {

    public HttpSession session;

    public void pushSession(String tag, Object o) {
        if (session == null) {
            session = currentContext();
        }
        session.setAttribute(tag, o);
    }

    public Object pullSession(String tag) {
        if (session == null) {
            session = currentContext();
        }
        return session.getAttribute(tag);
    }

    public void removeSession(String tag) {
        if (session == null) {
            session = currentContext();
        }
        session.removeAttribute(tag);
    }

    public void clearSession() {
        if (session == null) {
            session = currentContext();
        }
        session.invalidate();
    }

    public HttpSession currentContext() {
        ExternalContext G = FacesContext.getCurrentInstance().getExternalContext();
        HttpSession sessions = (HttpSession) G.getSession(false);
        return sessions;
    }
}

In the managed bean I instantiate the SessionLoader class to use its methods.

public class AccessBean implements java.io.Serializable{


    private   SessionLoader loader = new SessionLoader();
    private String connectedUserName;
public void logoutUser() throws IOException {
        try {
            loader.clearSession();
        } catch (Exception e) {
            e.printStackTrace(System.out);
        }
        ExternalContext ec = FacesContext.getCurrentInstance().getExternalContext();
        ec.redirect(ec.getRequestContextPath());
    }
}

during the deployment of the application in GlassFish the following error became

INFO: PWC2785: Cannot serialize session attribute accessBean for session eafd3249004855a2b1d6e8eb0f8c
java.io.NotSerializableException: ccf.sicav.sessions.SessionLoader
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1180)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1528)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1493)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1416)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:346)
    at org.apache.catalina.session.StandardSession.writeObject(StandardSession.java:2067)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:975)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1480)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1416)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:346)
    at org.apache.catalina.session.StandardManager.writeSessions(StandardManager.java:700)
    at com.sun.enterprise.web.WebModule.saveSessions(WebModule.java:1541)
    at com.sun.enterprise.web.WebContainer.unloadWebModule(WebContainer.java:2229)
    at com.sun.enterprise.web.WebContainer.unloadWebModule(WebContainer.java:2185)
    at com.sun.enterprise.web.WebApplication.stop(WebApplication.java:159)
    at org.glassfish.internal.data.EngineRef.stop(EngineRef.java:169)
    at org.glassfish.internal.data.ModuleInfo.stop(ModuleInfo.java:302)
    at org.glassfish.internal.data.ApplicationInfo.stop(ApplicationInfo.java:329)
    at com.sun.enterprise.v3.server.ApplicationLifecycle.unload(ApplicationLifecycle.java:998)
    at com.sun.enterprise.v3.server.ApplicationLifecycle.undeploy(ApplicationLifecycle.java:1024)
    at org.glassfish.deployment.admin.UndeployCommand.execute(UndeployCommand.java:330)
    at com.sun.enterprise.v3.admin.CommandRunnerImpl$1.execute(CommandRunnerImpl.java:348)
    at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:363)
    at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:1085)
    at com.sun.enterprise.v3.admin.CommandRunnerImpl.access$1200(CommandRunnerImpl.java:95)
    at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1291)
    at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1259)
    at com.sun.enterprise.v3.admin.AdminAdapter.doCommand(AdminAdapter.java:461)
    at com.sun.enterprise.v3.admin.AdminAdapter.service(AdminAdapter.java:212)
    at com.sun.grizzly.tcp.http11.GrizzlyAdapter.service(GrizzlyAdapter.java:179)
    at com.sun.enterprise.v3.server.HK2Dispatcher.dispath(HK2Dispatcher.java:117)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$Hk2DispatcherCallable.call(ContainerMapper.java:354)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:722)

how I solve this problem, I can change what class SessionLoader?

Answer 1

You should not try to Serialize your SessionLoader class as it has HttpSession object, Just make your SessionLoader transient.

private transient  SessionLoader loader = new SessionLoader();

But you can still serialize the contents of your session attributes, for that you need to first iterate through your session attributes and serialize individually.