pig/src/main/java/com/twitter/elephantbird/pig/store/BaseStoreFunc.java
protected void incrCounter(Pair<String, String> groupCounterPair, long incr) {
    counterHelper.incrCounter(groupCounterPair.first, groupCounterPair.second, incr);
  }
protected void incrCounter(Pair<String, String> groupCounterPair, long incr) {
    counterHelper.incrCounter(groupCounterPair.first, groupCounterPair.second, incr);
  }
same as incrCounter(pair.first, pair.second, incr).