How to build a model programmatically ?

Hi,
I've just seen  that the message I posted yesterday had a little problem 
of date (send in 2002...).
I don't  know if you received it, so I post it once again. Sorry if it 
was not necessary....



Hi everybody,
thanks a lot for your advice. Now I can handle my metaconcepts as I 
wanted to do.
But I still have a problem... When I try to write it in an xmi file (I 
just do the same thing as in the java code example posted by Antony), I 
get the following exceptions :



javax.jmi.reflect.InvalidCallException
    at 
org.netbeans.mdr.handlers.InstanceHandler.refGetValue(InstanceHandler.java:376)
    at 
org.netbeans.lib.jmi.xmi.WriterBase.writeReference(WriterBase.java:1044)
    at 
org.netbeans.lib.jmi.xmi.WriterBase.writeInstance(WriterBase.java:741)
    at org.netbeans.lib.jmi.xmi.WriterBase.writePackage(WriterBase.java:638)
    at org.netbeans.lib.jmi.xmi.WriterBase.writePackage(WriterBase.java:654)
    at 
org.netbeans.lib.jmi.xmi.WriterBase.writeDocument(WriterBase.java:551)
    at org.netbeans.lib.jmi.xmi.WriterBase.write(WriterBase.java:224)
    at org.netbeans.lib.jmi.xmi.WriterBase.write(WriterBase.java:195)
    at 
org.netbeans.lib.jmi.xmi.DelegatingWriter.write(DelegatingWriter.java:45)
    at org.netbeans.api.xmi.XMIWriter.write(XMIWriter.java:77)
    at MDRTest.main(MDRTest.java:84)



In the JMI specification, I can read that InvalidCallException are 
"Thrown by reflection methods when client tries to call them 
incorrectly. (e.g. when refSetValue is called for attribute which is not 
changeable)" (?!?!)
Is this problem frequent ? Do you have an idea ?



Regards, and thank you again for your advice.