@Test
public final void testBuildMessageFileListJsonWhenThereAreFewerMessagesThanTheLimit() {

    //GIVEN
    String expected = "{\"files\":[\"20130829103650.0000resp.txt\",\"20130829103651.0000req.txt\"]}";
    String[] fileNames = {"20130829103651.0000req.txt", "20130829103650.0000resp.txt"};
    given(file.list()).willReturn(fileNames);
    //WHEN
    String actual = underTest.buildMessageFileListJson(file, 5);
    //THEN
    assertEquals(actual, expected);
}