/**
* Destroy the store
*
* @throws IOException if it has difficulty removing the log files
*/
public void destroy() throws IOException {
// Prep all the sub-stores to be destroyed
for (SubStore subStore : subStores) {
subStore.prepareDestroy();
}
log.deletePersistentStore();
FileSystem.destroy(storeLocation, true);
}
/**
* Log an update. Will flush to disk before returning.
*
* @param o Update argument
* @throws IllegalStateException if the current thread does not hold a non-exclusive mutator lock
* @throws IOException If errors accessing the file system occur
*/
public void update(Object o) throws IOException {
final Long lockStateVal = lockState.get();
if (lockStateVal == null || lockStateVal == 0)
throw new IllegalStateException(
"PersistentStrore.update:" + "Must acquire mutator lock before calling update()");
synchronized (this) {
log.update(o, true);
updateCount++;
snapshotHandler.updatePerformed(updateCount);
}
}
/**
* Close this PersistentStore without destroying its contents
*
* @throws IOException If file system access errors are encountered
*/
public void close() throws IOException {
try {
// Using write lock because we want an exclusive lock
mutatorLock.writeLock();
updateCount = 0;
// Don't need to sync on this because
// mutatorLock.writeLock() gives us an exclusive lock
log.close();
} finally {
// Using write lock because we want an exclusive lock
mutatorLock.writeUnlock();
}
}
/**
* Construct a store that will persist its data to the specified directory.
*
* @param logDir Directory where the store should persist its data. must exist.
* @param logHandler Object that will process the log and last snapshot to recover the server's
* state
* @param snapshotHandler the server is called back after an update so it can decide whether or
* not to do a snapshot.
* @throws StoreException if there is a problem setting up the store
*/
public PersistentStore(String logDir, LogHandler logHandler, SnapshotHandler snapshotHandler)
throws StoreException {
this.snapshotHandler = snapshotHandler;
storeLocation = new File(logDir);
try {
log = new ReliableLog(storeLocation.getCanonicalPath(), logHandler);
} catch (IOException e) {
throw new CorruptedStoreException("Failure creating reliable log", e);
}
try {
log.recover();
} catch (IOException e) {
throw new CorruptedStoreException("Failure recovering reliable log", e);
}
}