@Test
public void testDirExistsWithValidDir()
{

    String dirName = FilenameUtils.concat( tmpDir, this.getDateTimeInMillis() );
    File f = new File( dirName );
    if ( f.mkdir() )
    {
        assertTrue( FileUtil.isDirExists( dirName ) );
    }
    if ( f.exists() )
    {
        f.delete();
    }
}