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I'm using Microsoft SQL Server with JSF.

I've been receiving this exception:

IOException while loading persisted sessions: java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: com.microsoft.sqlserver.jdbc.SQLServerConnection
java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: com.microsoft.sqlserver.jdbc.SQLServerConnection
    at java.io.ObjectInputStream.readObject0(Unknown Source)
    at java.io.ObjectInputStream.defaultReadFields(Unknown Source)
    at java.io.ObjectInputStream.readSerialData(Unknown Source)
    at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
    at java.io.ObjectInputStream.readObject0(Unknown Source)
    at java.io.ObjectInputStream.defaultReadFields(Unknown Source)
    at java.io.ObjectInputStream.readSerialData(Unknown Source)
    at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
    at java.io.ObjectInputStream.readObject0(Unknown Source)
    at java.io.ObjectInputStream.defaultReadFields(Unknown Source)
    at java.io.ObjectInputStream.readSerialData(Unknown Source)
    at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
    at java.io.ObjectInputStream.readObject0(Unknown Source)
    at java.io.ObjectInputStream.readObject(Unknown Source)
    at org.apache.catalina.session.StandardSession.readObject(StandardSession.java:1587)
    at org.apache.catalina.session.StandardSession.readObjectData(StandardSession.java:1060)
    at org.apache.catalina.session.StandardManager.doLoad(StandardManager.java:284)
    at org.apache.catalina.session.StandardManager.load(StandardManager.java:204)
    at org.apache.catalina.session.StandardManager.startInternal(StandardManager.java:470)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5169)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1033)
    at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:774)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1033)
    at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:291)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.StandardService.startInternal(StandardService.java:443)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:726)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:620)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:303)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:431)
Caused by: java.io.NotSerializableException: com.microsoft.sqlserver.jdbc.SQLServerConnection
    at java.io.ObjectOutputStream.writeObject0(Unknown Source)
    at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
    at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
    at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
    at java.io.ObjectOutputStream.writeObject0(Unknown Source)
    at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
    at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
    at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
    at java.io.ObjectOutputStream.writeObject0(Unknown Source)
    at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
    at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
    at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
    at java.io.ObjectOutputStream.writeObject0(Unknown Source)
    at java.io.ObjectOutputStream.writeObject(Unknown Source)
    at org.apache.catalina.session.StandardSession.writeObject(StandardSession.java:1663)
    at org.apache.catalina.session.StandardSession.writeObjectData(StandardSession.java:1077)
    at org.apache.catalina.session.StandardManager.doUnload(StandardManager.java:411)
    at org.apache.catalina.session.StandardManager.unload(StandardManager.java:353)
    at org.apache.catalina.session.StandardManager.stopInternal(StandardManager.java:497)
    at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:225)
    at org.apache.catalina.core.StandardContext$4.call(StandardContext.java:5391)
    at org.apache.catalina.core.StandardContext$4.call(StandardContext.java:5374)
    at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

I've set the Java Bean related to the SQL Server as implements Serializable, for example

@ManagedBean
@SessionScoped
public class SqlBean implements Serializable {

    private Connection  conn = null;

    public SqlBean() {
        super();
        System.out.println("Starts to read!");
        String dbName = "//some dbName";
        String serverip="//some serverip";
        String serverport="//some serverport";
        String url = "jdbc:sqlserver://"+serverip+"\\SQLEXPRESS:"+serverport+";databaseName="+dbName+"";
        String driver = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
        String databaseUserName = "//some user";
        String databasePassword = "//some password";
        try {
            Class.forName(driver).newInstance();
            conn = DriverManager.getConnection(url, databaseUserName, databasePassword);
            if(conn!=null) System.out.println("Connection Successful!");
        }catch(Exception e){
            e.printStackTrace();
            System.out.println("Error Trace in getConnection() : " + e.getMessage());
        }
    }
}

The connection is always successful. Totally lost on this. Any help will be greatly appreciated.

ethanjyx
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1 Answers1

2

This is very wrong in 2 ways:

//resource injection
private Connection  conn = null;
  1. This is definitely not resource injection.
  2. Keeping a connection open that long and sharing it across multiple requests in a HTTP session is bad design and not threadsafe.

You should rewrite all your JDBC code in such way that you acquire and close all DB resources Connection, (Prepared)Statement and ResultSet in the shortest possible scope in the very same try-finally block.

Your concrete problem is caused because a DB connection does not implement Serializable for the very simple reason that a TCP/IP connection can't be serializable.

See also:

Please note that this problem is completely unrelated to JSF. You should put all that JDBC code in standalone DAO classes and make sure that all your JSF managed beans are completely free of java.sql imports. To get a step further, start learning EJB and JPA. This way all the DB interaction can be done in oneliners without any need for all the raw connection/statement/resultset mess. That's also the path you're supposed to follow if you want to go Java EE.

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BalusC
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  • Is using transient a bad practice? – ethanjyx Aug 26 '13 at 14:40
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    Depends on whether it's been used as a solution or a workaround. If as a workaround, then it's definitely bad. My answer describes the solution. If you'd use `transient` instead of applying my answer, then it'd be a workaround. You're merely postponing/moving/hiding the real problem instead of really fixing it. – BalusC Aug 26 '13 at 14:51
  • Why is it bad? I'm using it as a workaround – ethanjyx Aug 26 '13 at 14:56
  • Because the problem as described in my answer still persists. – BalusC Aug 26 '13 at 15:01