TarRevisions implements Revisions, Closeable { @NotNull @Override public RecordId getHead() { checkBound(); return head.get(); } TarRevisions(SegmentNodeStorePersistence persistence); static Option timeout(long time, TimeUnit unit); @NotNull @Override RecordId getHead(); @NotNull @Override RecordId getPersistedHead(); @Override boolean setHead(
            @NotNull RecordId expected,
            @NotNull RecordId head,
            @NotNull Option... options); @Override RecordId setHead(
            @NotNull Function<RecordId, RecordId> newHead,
            @NotNull Option... options); @Override void close(); static final Option EXPEDITE_OPTION; static final Option INFINITY; }
@Test(expected = IllegalStateException.class) public void unboundRevisions() throws IOException { try (TarRevisions tarRevisions = new TarRevisions(getPersistence())) { tarRevisions.getHead(); } }
@Test public void getHead() throws IOException { try (JournalReader reader = createJournalReader()) { assertTrue(reader.hasNext()); assertEquals(revisions.getHead().toString10(), reader.next().getRevision()); } }