First, thanks for the response, I appreciate it!

Hmm, I thought I was doing most of what you suggested, in that I do limit all
access to the KeyFactory to a single entry point that has the tx attribute
"RequiresNew" (but it isn't a home method, so I'll make that change). And I
didn't think that I had any other existing transactions that would be holding
on to a lock to the key factory, but suffering from newbieosis I'm probably
overlooking something, so I'll take a closer look. I'll let you know what
I find.

Paul

I'm still perplexed, dazed and confused ...

The code that's causing me grief is a primary key generator, and
is loosely based on code packaged with Floyd Marinescu's book,
"EJB Design Patterns". I figured that something must have been
lost in the translation from his code to mine, so I decided to
use his code as a baseline. Oops, the problem didn't go away.
So, I thought that it must be something in the rest of my code
that was causing the problem, so I took his code (an entity bean
and a session bean) and plopped it down in the crime portal
example.

In "GangsterBean.ejbCreate" I added:
[pre]
SequenceSessionLocalHome home;
try {
home = (SequenceSessionLocalHome)((new javax.naming.InitialContext()).lookup("SequenceSessionLocal"));
}
catch(javax.naming.NamingException e) {
throw new CreateException(e.getExplanation());
}
SequenceSessionLocal sequence = home.create();
int number = sequence.getNextSequenceNumber("GANGSTER");
System.err.println("Next Number: " + number);
[/pre]
I also made the (hopefully) appropriate entries in "ejb-jar.xml",
"jboss.xml", and "jbosscmp-jdbc.xml" (I've included the entries I
made at the end of this message).

I then ran "ant" followed by "ant setup", and still with the...
[pre]
[junit] Caused by: org.jboss.ejb.plugins.lock.ApplicationDeadlockException: Application deadlock detected: Current thread already has tx lock in different transaction.
[/pre]
So, I'm at a loss. Any thoughts on what else I might check? Or,
is this possibly a JBoss problem?

Any and all help is appreciated, thanks,

Paul

Following are the snippets I added to the deployment descriptors
[pre]
In "ejb-jar.xml":

<ejb-name>SequenceSession</ejb-name>

<local-home>org.jboss.docs.cmp2.crimeportal.SequenceSessionLocalHome</local-home>
org.jboss.docs.cmp2.crimeportal.SequenceSessionLocal
<ejb-class>org.jboss.docs.cmp2.crimeportal.SequenceSessionBean</ejb-class>

<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>



<ejb-name>Sequence</ejb-name>

<local-home>org.jboss.docs.cmp2.crimeportal.SequenceLocalHome</local-home>
org.jboss.docs.cmp2.crimeportal.SequenceLocal
<ejb-class>org.jboss.docs.cmp2.crimeportal.SequenceBean</ejb-class>

<persistence-type>Container</persistence-type>
<prim-key-class>java.lang.String</prim-key-class>
False
<cmp-version>2.x</cmp-version>
<abstract-schema-name>SequenceBean</abstract-schema-name>

<cmp-field><field-name>index</field-name></cmp-field>
<cmp-field><field-name>name</field-name></cmp-field>

<primkey-field>name</primkey-field>


<container-transaction>

<ejb-name>Sequence</ejb-name>
<method-name>getValueAfterIncrementingBy</method-name>

<trans-attribute>RequiresNew</trans-attribute>
</container-transaction>

In "jboss.xml":


<ejb-name>SequenceSession</ejb-name>
<local-jndi-name>SequenceSessionLocal</local-jndi-name>



<ejb-name>Sequence</ejb-name>
<local-jndi-name>SequenceLocalHome</local-jndi-name>


In "jbosscmp-jdbc.xml":


<ejb-name>Sequence</ejb-name>
<table-name>sequences</table-name>

<cmp-field>
<field-name>index</field-name>
<column-name>index</column-name>
</cmp-field>
<cmp-field>
<field-name>name</field-name>
<column-name>name</column-name>
</cmp-field>

[/pre]

Thanks for taking the time to help me out, I do appreciate it.

I probably will use JBoss's autonumber code, but I'm still curious
what the problem is. The main reason I've spent so much time on
this problem is that I don't understand its cause, and being new
to this stuff I thought that it would be reasonable to figure it
out ... otherwise, I'll just make similar mistakes down the road.

That said, I hope I'm not being too much of a time sink if I ask
you what "fault creating" is. I searched for that term (on the web,
in your book, and in the quick start guide) and have so far come up
with nothing. Even a pointer to a place to look would be appreciated.

Once again thanks for your time,

Paul

Thanks, I think I do follow.

Below is the method from Floyd's session bean (I removed some exception handling
to shorten it up).
[pre]
public int getNextSequenceNumber(String name) {
try {
Entry entry = (Entry) _entries.get(name);
if (entry == null) {
entry = new Entry(); // add an entry to the sequence table
try {
entry.sequence = _sequenceHome.findByPrimaryKey(name);
}
catch (javax.ejb.FinderException e) {
entry.sequence = _sequenceHome.create(name);
[/pre]
So when this new sequence is created, it is locked with the transaction covering
the invocation of "getNextSequenceNumber"
[pre]
}
_entries.put(name, entry);
}
if (entry.last % _blockSize == 0) {
entry.last = entry.sequence.getValueAfterIncrementingBy(_blockSize);
[/pre]
and here we deadlock since "getValueAfterIncrementingBy" has a transaction
attribute of "RequiresNew" and sequence is already locked
[pre]
}
return entry.last++;
}
catch (javax.ejb.CreateException e) {
throw new javax.ejb.EJBException(e);
}
}
[/pre]

Thanks for all the time you've spent helping me out!

Paul