### Question:
FileObjectStore implements ParseObjectStore<T> { @Override public Task<Boolean> existsAsync() { return Task.call(new Callable<Boolean>() { @Override public Boolean call() throws Exception { return file.exists(); } }, ParseExecutors.io()); } FileObjectStore(Class<T> clazz, File file, ParseObjectCurrentCoder coder);  FileObjectStore(String className, File file, ParseObjectCurrentCoder coder); @Override Task<Void> setAsync(final T object); @Override Task<T> getAsync(); @Override Task<Boolean> existsAsync(); @Override Task<Void> deleteAsync();  }### Answer:
@Test public void testExistsAsync() throws Exception { File file = temporaryFolder.newFile("test"); FileObjectStore<ParseUser> store = new FileObjectStore<>(ParseUser.class, file, null); assertTrue(ParseTaskUtils.wait(store.existsAsync())); temporaryFolder.delete(); assertFalse(ParseTaskUtils.wait(store.existsAsync())); }