One of our users got this when they restarted our application after it was abruptly terminated (not sure what happened, maybe someone pulled the plug on the machine or killed the process while it was writing to the Derby database). We are using Derby in embedded mode on the local hard drive.

Is Derby supposed to be resilient to this kind of circumstance? Or should I just expect that the database may well be unrecoverable in the case of an abnormal termination (requiring the user to resort to a backup)?

----------------------------------------------------------------
2008-07-23 14:54:36.861 GMT:
 Booting Derby version The Apache Software Foundation - Apache Derby - 10.4.1.3 - (648739): instance a816c00e-011b-506a-1bb3-fffff8e54afd
on database directory C:\Program Files\My Company\Server\db\data 


------------  BEGIN SHUTDOWN ERROR STACK -------------

ERROR XSLA6: Cannot recover the database.
    at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
    at org.apache.derby.impl.store.raw.log.LogToFile.recover(Unknown Source)
    at org.apache.derby.impl.store.raw.RawStore.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.access.RAMAccessManager.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.bootStore(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.bootService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startProviderService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.findProviderAndStartService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startPersistentService(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.startPersistentService(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.bootDatabase(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.<init>(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection30.<init>(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection40.<init>(Unknown Source)
    at org.apache.derby.jdbc.Driver40.getNewEmbedConnection(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
    at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
Caused by: java.lang.ClassCastException: org.apache.derby.impl.store.access.btree.index.B2IUndo cannot be cast to org.apache.derby.impl.store.raw.log.LogRecord
    at org.apache.derby.impl.store.raw.log.Scan.getNextRecordForward(Unknown Source)
    at org.apache.derby.impl.store.raw.log.Scan.getNextRecord(Unknown Source)
    at org.apache.derby.impl.store.raw.log.FileLogger.readLogRecord(Unknown Source)
    at org.apache.derby.impl.store.raw.log.LogToFile.findCheckpoint(Unknown Source)
    ... 35 more
============= begin nested exception, level (1) ===========
java.lang.ClassCastException: org.apache.derby.impl.store.access.btree.index.B2IUndo cannot be cast to org.apache.derby.impl.store.raw.log.LogRecord
    at org.apache.derby.impl.store.raw.log.Scan.getNextRecordForward(Unknown Source)
    at org.apache.derby.impl.store.raw.log.Scan.getNextRecord(Unknown Source)
    at org.apache.derby.impl.store.raw.log.FileLogger.readLogRecord(Unknown Source)
    at org.apache.derby.impl.store.raw.log.LogToFile.findCheckpoint(Unknown Source)
    at org.apache.derby.impl.store.raw.log.LogToFile.recover(Unknown Source)
    at org.apache.derby.impl.store.raw.RawStore.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.access.RAMAccessManager.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.bootStore(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.bootService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startProviderService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.findProviderAndStartService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startPersistentService(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.startPersistentService(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.bootDatabase(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.<init>(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection30.<init>(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection40.<init>(Unknown Source)
    at org.apache.derby.jdbc.Driver40.getNewEmbedConnection(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
    at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
============= end nested exception, level (1) ===========


------------  END SHUTDOWN ERROR STACK -------------