@Test
public void testGetFileExtension() {

    assertEquals( "txt", FileUtils.getFileExtension( new File( "/tmp/foo.txt" ) ) );
    assertEquals( "txt", FileUtils.getFileExtension( new File( "/tmp/foo.bar.txt" ) ) );
    assertEquals( "", FileUtils.getFileExtension( new File( "/tmp/foo.bar." ) ) );
    assertEquals( "", FileUtils.getFileExtension( new File( "/tmp/foo" ) ) );
    assertEquals( "", FileUtils.getFileExtension( new File( "/tmp.dir/foo" ) ) );
    assertEquals( "", FileUtils.getFileExtension( new File( "" ) ) );
}