I'm using hibernate 3 with c3p0 for a program which constantly extracts data from some source and writes it to a database. Now the problem is, that the database might become unavailable for some reasons (in the simplest case: i simply shut it down).
If anything is about to be written to the database there should not be any exception - the query should wait for all eternity until the database becomes available again. If I'm not mistaken this is one of the things the connection pool could do for me: if there is a problem with the db, just retry to connect - in the worst case for infinity.
But instead i get a broken pipe exception, sometimes followed by connection refused and then the exception is passed to my own code, which shouldn't happen.
Even if I catch the exception, how could i cleanly reinitialize hibernate again? (So far without c3p0 i simply built the session factory again, but i wouldn't be surprised if that could leak connections (or is it ok to do so?)).
The database is Virtuoso open source edition.
My hibernate.xml.cfg c3p0 config:
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.breakAfterAcquireFailure">false</property>
<property name="hibernate.c3p0.acquireRetryAttempts">-1</property>
<property name="hibernate.c3p0.acquireRetryDelay">30000</property>
<property name="hibernate.c3p0.automaticTestTable">my_test_table</property>
<property name="hibernate.c3p0.initialPoolSize">3</property>
<property name="hibernate.c3p0.minPoolSize">3</property>
<property name="hibernate.c3p0.maxPoolSize">10</property>
btw: The test table is created and i get tons of debug output- so it seems it actually reads the config.
Well it seems that BoneCP has actually implemented this. It can be set to record the transaction and replay it upon network or database failure: