@Test
public void testSingleThreaded() throws IOException {
Configuration conf = new Configuration();
MiniJournalCluster cluster = new MiniJournalCluster.Builder(conf).build();
URI uri = cluster.getQuorumJournalURI(JID);
QuorumJournalManager qjm = new QuorumJournalManager(conf, uri, FAKE_NSINFO,
null, false);
try {
qjm.transitionJournal(FAKE_NSINFO, Transition.FORMAT, null);
} finally {
qjm.close();
}
try {
// With no failures or contention, epochs should increase one-by-one
for (int i = 0; i < 5; i++) {
qjm = new QuorumJournalManager(conf, uri, FAKE_NSINFO, null, false);
try {
qjm.createNewUniqueEpoch();
assertEquals(i + 1, qjm.getLoggerSetForTests().getEpoch());
} finally {
qjm.close();
}
}
long prevEpoch = 5;
// With some failures injected, it should still always increase, perhaps
// skipping some
for (int i = 0; i < 20; i++) {
long newEpoch = -1;
while (true) {
qjm = new QuorumJournalManager(conf, uri, FAKE_NSINFO,
new FaultyLoggerFactory(), null, false);
try {
qjm.createNewUniqueEpoch();
newEpoch = qjm.getLoggerSetForTests().getEpoch();
break;
} catch (IOException ioe) {
// It's OK to fail to create an epoch, since we randomly inject
// faults. It's possible we'll inject faults in too many of the
// underlying nodes, and a failure is expected in that case
} finally {
qjm.close();
}
}
LOG.info("Created epoch " + newEpoch);
assertTrue("New epoch " + newEpoch
+ " should be greater than previous " + prevEpoch,