@Test
public void testFilesystemCounter() {

  GroupFactory groupFactory = new GroupFactoryForTest();
  Group fsGroup = groupFactory.newFileSystemGroup();

  org.apache.hadoop.mapreduce.Counter count1 = 
      fsGroup.findCounter("ANY_BYTES_READ");
  Assert.assertNotNull(count1);
  
  // Verify no exception get thrown when finding an unknown counter
  org.apache.hadoop.mapreduce.Counter count2 = 
      fsGroup.findCounter("Unknown");
  Assert.assertNull(count2);
}