Hi,

I have 2 stateless container managed transaction beans called OrderSLB and ContractSLB and one CMP bean
OrderEB wrapping around an order table.

The orderslb has a method called updateOrder() defined with a Required attribute. This method does the
update on the order row be looking up the OrderEB bean by findByPrimaryKey() (...besides some other
operation ...)

The second bean contract bean has a method called executeContract() been defined with Required attribute.
This method does 3 things

1) Check for business validity.

2)updates a status field in the order table so looks up the orderEB to do the job

3) Inserts a record in the Contract table.

The ordereb has ben set with a serializable transcation isolation

When 2 user do a simultaneous where one does an updateOrder() and one and executeContract() I want only
one user to succeed and i should be able to give an error message to the other user.

Now i get a number of outputs when i try to do the operations simultaneously. One of them is : the updateorders()
happenes first, then the update of status on the executeContract(). (note this happens between the validity
check and the change of status...) Businesswise this is a bad situation. How do i prevent this ? How
do i implement locking so that i know when i start the trasaction for exceuteContract() the order will
not be updated

Saba