code: public void testScannerLeak(){
    List<KeyValue> l1=new ArrayList<KeyValue>();
    l1.add(new KeyValue(row1,fam1,col5,data));
    l1.add(new KeyValue(row2,fam1,col1,data));
    l1.add(new KeyValue(row2,fam1,col2,data));
    scanners.add(new Scanner(l1));
    List<KeyValue> l2=new ArrayList<KeyValue>();
    l2.add(new KeyValue(row1,fam1,col1,data));
    l2.add(new KeyValue(row1,fam1,col2,data));
    scanners.add(new Scanner(l2));
    List<KeyValue> l3=new ArrayList<KeyValue>();
    l3.add(new KeyValue(row1,fam1,col3,data));
    l3.add(new KeyValue(row1,fam1,col4,data));
    l3.add(new KeyValue(row1,fam2,col1,data));
    l3.add(new KeyValue(row1,fam2,col2,data));
    l3.add(new KeyValue(row2,fam1,col3,data));
    scanners.add(new Scanner(l3));
    List<KeyValue> l4=new ArrayList<KeyValue>();
    scanners.add(new Scanner(l4));
    KeyValueHeap kvh=new KeyValueHeap(scanners.toArray(new Scanner[0]),KeyValue.COMPARATOR);
    while (kvh.next() != null)   ;
    for (  Scanner scanner : scanners) {
      assertTrue(scanner.isClosed());
    }
  }
  