source: class BandedUpdaterTest {
  
      @Test
      public void testBasic()
      {
  
target:         TreeMap<String, HashSet<String> > map=new TreeMap<String, HashSet<String>>();
  
          BandedUpdater<String, String> bu = new BandedUpdater<String,String>(map,2);
  
          bu.addItem("a","cow");
          bu.addItem("a","wolf");
          bu.addItem("a","tomato");
  
          Assert.assertEquals(1, map.size());
          Assert.assertEquals(3, map.get("a").size());
  
          bu.addItem("b","tomato");
          Assert.assertEquals(2, map.size());
          
      }
  
  }