public EntryWriter launchEntryWriter(SequenceFile.Writer writer, int capacity) {
    final EntryWriter ew = new EntryWriter(writer, capacity);
    ew.start();
    return ew;
  }
@Test
  public void testCreateInvalidWriterCapacity() throws Throwable {
    intercept(IllegalStateException.class, () ->
        entryFileIO.launchEntryWriter(null, 0));
  }