public void add(Item item) {
    String typeName = item.typeName();
    Data data = dataMap.get(typeName);

    if (data == null) {
      dataMap.put(typeName, new Data(item, typeName));
    } else {
      data.add(item);
    }
  }
Adds the given item to the statistics.

@param item {@code non-null;} the item to add
android/android_framework/dex-maker/src/main/java/com/android/dx/dex/file/Statistics.java