/**
* Run a block of code in a JPA transaction.
*
* @param name The persistence unit name
* @param readOnly Is the transaction read-only?
* @param block Block of code to execute
*/
public <T> T withTransaction(String name, boolean readOnly, Supplier<T> block) {
EntityManager entityManager = null;
EntityTransaction tx = null;
try {
entityManager = em(name);
if (entityManager == null) {
throw new RuntimeException("No JPA entity manager defined for '" + name + "'");
}
JPA.bindForSync(entityManager);
if (!readOnly) {
tx = entityManager.getTransaction();
tx.begin();
}
T result = block.get();
if (tx != null) {
if (tx.getRollbackOnly()) {
tx.rollback();
} else {
tx.commit();
}
}
return result;
} catch (Throwable t) {
if (tx != null) {
try {
tx.rollback();
} catch (Throwable e) {
}
}
throw t;
} finally {
JPA.bindForSync(null);
if (entityManager != null) {
entityManager.close();
}
}
}
