Possible to use a TreeMap?

[Neil Aggarwal <neil@JAMMConsulting.com>]

Hello:

I have a basic question:  One of my database objects
contains other objects in a TreeMap, but when I try to add
more than one object to the TreeMap, I get this exception:

    java.lang.ClassCastException: persistent.FileRecordImpl_Proxy
        at java.util.TreeMap.compare(TreeMap.java:1047)
        at java.util.TreeMap.put(TreeMap.java:449)
        at java.util.TreeSet.add(TreeSet.java:198)
        at persistent.ControllerImpl.addFile(ControllerImpl.java:45)
        at java.lang.reflect.Method.invoke(Native Method)
        at
org.ozoneDB.core.AbstractObjectContainer.invokeTarget(AbstractObje
            ctContainer.java:207)
        at
org.ozoneDB.core.Transaction.invokeObject(Transaction.java:498)
        at org.ozoneDB.core.DbRemote.DbInvoke.perform(DbInvoke.java:62)
        at
org.ozoneDB.core.Transaction.performCommand(Transaction.java:265)
        at
org.ozoneDB.core.TransactionManager.performCommand(TransactionMana
            ger.java:348)
        at
org.ozoneDB.core.TransactionManager.completeTransaction(Transactio
            nManager.java:315)
        at
org.ozoneDB.core.TransactionManager.handleCommand(TransactionManag
            er.java:230)
        at
org.ozoneDB.core.InvokeServer.handleClientEvent(InvokeServer.java:
            75)
        at
org.ozoneDB.DxLib.net.DxMultiServerClient.run(DxMultiServerClient.
            java:41)
        at java.lang.Thread.run(Thread.java:484)

Is it possible to use a TreeMap in a database class?

Thanks,
	Neil.

--
Neil Aggarwal
JAMM Consulting, Inc. -- (972) 612-6056, http://www.JAMMConsulting.com
Custom Internet Development -- Java, JSP, servlets, databases