You’re probably not going to like this answer, but… Voting inside a nested scope Although a nested scope can join the ambient transaction of the root scope, calling Complete in the nested scope has no affect on the root scope. Only if all the scopes from the root scope down to the last nested scope … Read more
This is defined behaviour. From the docs: Any RuntimeException triggers rollback, and any checked Exception does not. This is common behaviour across all Spring transaction APIs. By default, if a RuntimeException is thrown from within the transactional code, the transaction will be rolled back. If a checked exception (i.e. not a RuntimeException) is thrown, then … Read more
I would first differentiate between optimistic and pessimistic locks, because they are different in their underlying mechanism. Optimistic locking is fully controlled by JPA and only requires additional version column in DB tables. It is completely independent of underlying DB engine used to store relational data. On the other hand, pessimistic locking uses locking mechanism … Read more
That is expected and documented behaviour: From the manual: Since these functions return the start time of the current transaction, their values do not change during the transaction. This is considered a feature: the intent is to allow a single transaction to have a consistent notion of the “current” time, so that multiple modifications within … Read more
As I understand catching Error will help us behave correctly even when something really bad happen. Or maybe it wouldn’t help? You don’t need to explicitly specify rollbackFor = Throwable.class, because spring will by default rollback the transaction if an Error occurs. See 1.4.3. Rolling Back a Declarative Transaction In its default configuration, the Spring … Read more
The javadoc for JpaTransactionManager has some advice on this: This transaction manager is appropriate for applications that use a single JPA EntityManagerFactory for transactional data access. JTA (usually through JtaTransactionManager) is necessary for accessing multiple transactional resources within the same transaction. Note that you need to configure your JPA provider accordingly in order to make … Read more
The simplest solution is to delegate the concurrency to your database and simply rely on the database isolation level lock on the currently modified rows: The increment is as simple as this: UPDATE Tag t set t.count = t.count + 1 WHERE t.id = :id; and the decrement query is: UPDATE Tag t set t.count … Read more
COMMIT may fail. You might have had sufficent resources to log all the changes you wished to make, but lack resources to actually implement the changes. And that’s not considering other reasons it might fail: The change itself might not fit the constraints of the database. Power loss stops things from completing. The level of … Read more
You could get exactly what you want by a simpler way, with TransactionSynchronizationManager and TransactionSynchronization With TransactionSynchronizationManager, you have static methods to get information about current transaction, and you can register a TransactionSynchronization wich allows you to automatically do a post-commit as you call that TransactionSynchronizationManager.registerSynchronization(new TransactionSynchronization(){ void afterCommit(){ //do what you want to do … Read more
I solved this by using a placeholder in my Layout and then attaching my Fragment to it at runtime. Like you, if I instantiated my Fragment within my xml layout then the contents would remain visible after replacing it with another Fragment at runtime.