### Question:
AvroStringUtils { @VisibleForTesting static String appendForwardSlashIfNotPresent(String path) { checkArgument(isNotBlank(path), "There must be a path provided"); if (path.charAt(path.length() - 1) == '/') { return path; } return path + "/"; } private  AvroStringUtils(); static String avroDestination(String pathToDestinationFolder, String eventId, String tableLocation); static boolean argsPresent(String... args);  }### Answer:
@Test public void appendForwardSlashWhenNoneIsPresent() { assertThat(appendForwardSlashIfNotPresent("test"), is("test/")); }
@Test public void doesntAppendSecondForwardSlashWhenOneIsPresent() { assertThat(appendForwardSlashIfNotPresent("test/"), is("test/")); }
@Test(expected = IllegalArgumentException.class) public void nullArgParamTest() { appendForwardSlashIfNotPresent(null); }
@Test(expected = IllegalArgumentException.class) public void emptyArgParamTest() { appendForwardSlashIfNotPresent(""); }