Address review comments.

core/server/common/src/main/java/alluxio/master/journal/ufs/UfsJournalLogWriter.java

@@ -194,11 +194,11 @@ public synchronized void write(JournalEntry entry) throws IOException {
       mEntriesToFlush.add(entryToWrite);
       mNextSequenceNumber++;
     } catch (IOException e) {
-      // Set mJournalOutputStream to null so that {@code maybeRecoverFromUfsFailures}
-      // can know a UFS failure has occurred.
       mRotateLogForNextWrite = true;
       UfsJournalFile currentLog = mJournalOutputStream.mCurrentLog;
       mJournalOutputStream = null;
+      // Set mNeedsRecovery to true so that {@code maybeRecoverFromUfsFailures}
+      // can know a UFS failure has occurred.
       mNeedsRecovery = true;
       throw new IOException(ExceptionMessage.JOURNAL_WRITE_FAILURE
           .getMessageWithUrl(RuntimeConstants.ALLUXIO_DEBUG_DOCS_URL,
@@ -393,27 +393,8 @@ public synchronized void close() throws IOException {
     mClosed = true;
   }
 
-  /**
-   * @return number of journal entries to flush stored in the queue
-   */
-  @VisibleForTesting
-  synchronized  int getNumberOfJournalEntriesToFlush() {
-    return mEntriesToFlush.size();
-  }
-
   @VisibleForTesting
   synchronized JournalOutputStream getJournalOutputStream() {
     return mJournalOutputStream;
   }
-
-  /**
-   * @return the current underlying {@link DataOutputStream} to write journal entries
-   */
-  @VisibleForTesting
-  synchronized DataOutputStream getUnderlyingDataOutputStream() {
-    if (mJournalOutputStream == null) {
-      return null;
-    }
-    return mJournalOutputStream.mOutputStream;
-  }
 }

tests/src/test/java/alluxio/master/journal/ufs/UfsJournalLogWriterTest.java

@@ -366,7 +366,6 @@ private DataOutputStream createMockDataOutputStream(UfsJournalLogWriter writer)
     DataOutputStream badOut = Mockito.mock(DataOutputStream.class);
     Object journalOutputStream = writer.getJournalOutputStream();
     Whitebox.setInternalState(journalOutputStream, "mOutputStream", badOut);
-    Assert.assertEquals(badOut, writer.getUnderlyingDataOutputStream());
     return badOut;
   }