How can i attach data to a JTA transaction? (or uniquely identify it)

I have a getStockQuote() function that will get a current stock quote for a symbol from the stock market.

My goal is that within a JTA transaction, the first call to getStockQuote() will fetch a stock quote, but all subsequent calls within the same transaction will reuse the same stock quote (e.g.: it will not try to fetch a new quote). If a different transaction starts, or another transaction runs concurrently, i would expect the other transaction to fetch its own stock quote on its first call.

This is to try to ensure consistency within the transaction - so that all calculations within the transaction are based on the same stock price.

This would be similar to how you can configure JPA providers to only fetch a database row from the database once, and use the cached value for subsequent access to the same database row within the transa开发者_如何学编程ction.

Does anyone have tips on how this can be achieved?

This would require some testing but I think that you could bind the quote to a ThreadLocal and make your beans implement SessionSynchronization to unbind the quote from the ThreadLocal after the commit of a transaction (and thus implement a kind of transaction-scoped context).

consider using spring for transaction management, it provides this functionality out of the box:

http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/transaction.html#tx-propagation