### Question:
FsPermissionToStringConverter extends StdConverter<FsPermission, String> { @Override public String convert(FsPermission value) { return toString(value); }  @Override String convert(FsPermission value); static String toString(FsPermission value);  }### Answer:
@Test public void testConvertWhenInputIsNotNull() { assertThat(new FsPermissionToStringConverter().convert(new FsPermission("640")), is("640")); }
@Test public void testConvertWhenInputIsNull() { assertThat(new FsPermissionToStringConverter().convert(null), is(nullValue())); }