code: @Test public void testGetFeatureState(){
    FileBasedStateRepository repo=new FileBasedStateRepository(file);
    FeatureState state1=repo.getFeatureState(MyFeature.FEATURE1);
    assertEquals(true,state1.isEnabled());
    assertEquals(Arrays.asList("chkal","tester"),state1.getUsers());
    FeatureState state2=repo.getFeatureState(MyFeature.FEATURE2);
    assertEquals(false,state2.isEnabled());
    assertEquals(Collections.emptyList(),state2.getUsers());
    FeatureState state3=repo.getFeatureState(MyFeature.FEATURE3);
    assertEquals(true,state3.isEnabled());
    assertEquals(Collections.emptyList(),state3.getUsers());
    FeatureState state4=repo.getFeatureState(MyFeature.FEATURE4);
    assertNull(state4);
  }
  