@Test
public void testCheck_missMatchInputAndOutput() {

  when(directory.listFiles()).thenReturn(
      new File[]{dataInput1, dataOutput1, dataInput2, dataOutput3});
  try {
    checker.check(directory);
    Assert.fail();
  } catch (AppException e) {
    Assert.assertEquals(e,
        new AppException("Some data files has not input file or output file."));
  }
}