### Question:
QuorumJournalManager implements JournalManager { @Override public void format(NamespaceInfo nsInfo) throws IOException { QuorumCall<AsyncLogger,Void> call = loggers.format(nsInfo); try { call.waitFor(loggers.size(), loggers.size(), 0, FORMAT_TIMEOUT_MS, "format"); } catch (InterruptedException e) { throw new IOException("Interrupted waiting for format() response"); } catch (TimeoutException e) { throw new IOException("Timed out waiting for format() response"); } if (call.countExceptions() > 0) { call.rethrowException("Could not format one or more JournalNodes"); } } QuorumJournalManager(Configuration conf,
      URI uri, NamespaceInfo nsInfo);   QuorumJournalManager(Configuration conf,
      URI uri, NamespaceInfo nsInfo,
      AsyncLogger.Factory loggerFactory); static void checkJournalId(String jid); @Override void format(NamespaceInfo nsInfo); @Override boolean hasSomeData(); @Override EditLogOutputStream startLogSegment(long txId); @Override void finalizeLogSegment(long firstTxId, long lastTxId); @Override void setOutputBufferCapacity(int size); @Override void purgeLogsOlderThan(long minTxIdToKeep); @Override void recoverUnfinalizedSegments(); @Override void close(); @Override void selectInputStreams(Collection<EditLogInputStream> streams,
      long fromTxnId, boolean inProgressOk); @Override String toString();  }### Answer:
@Test public void testFormat() throws Exception { QuorumJournalManager qjm = closeLater(new QuorumJournalManager( conf, cluster.getQuorumJournalURI("testFormat-jid"), FAKE_NSINFO)); assertFalse(qjm.hasSomeData()); qjm.format(FAKE_NSINFO); assertTrue(qjm.hasSomeData()); }