code: @Test public void testBatchMutationManagement(){
    String cf="Standard1";
    Mutator<String> m=createMutator(keyspace,se);
    for (int i=0; i < 5; i++) {
      m.addInsertion("k" + i,cf,createColumn("name","value" + i,se,se));
    }
    MutationResult r=m.execute();
    assertTrue("Execute time should be > 0",r.getExecutionTimeMicro() > 0);
    assertTrue("Should have operated on a host",r.getHostUsed() != null);
    for (int i=0; i < 5; i++) {
      assertColumnExists("Keyspace1","Standard1","k" + i,"name");
    }
    r=m.execute();
    assertEquals("Execute time should be 0",0,r.getExecutionTimeMicro());
    for (int i=0; i < 5; i++) {
      m.addInsertion("k" + i,cf,createColumn("name","value" + i,se,se));
    }
    m.discardPendingMutations();
    r=m.execute();
    assertEquals("Execute time should be 0",0,r.getExecutionTimeMicro());
    assertTrue("Should have operated with a null host",r.getHostUsed() == null);
    for (int i=0; i < 5; i++) {
      m.addDeletion("k" + i,cf,"name",se);
    }
    m.execute();
  }
  