Exemplo n.º 1
0
  /**
   * Uses Reflection to create a new {@link AbstractCard} from the given {@link CardModel} by
   * copying fields.
   *
   * @param model The {@link CardModel} to "inflate" into an {@link AbstractCard}
   * @return An {@link AbstractCard} that matches the model data
   * @throws InstantiationException Thrown when the class specified by the model cannot be
   *     instantiated (no default ctor).
   * @throws IllegalAccessException Thrown if I missed a setAccessible(true) somewhere, or if the
   *     default ctor for the target class is not visible.
   */
  public static AbstractCard createCard(CardModel model)
      throws InstantiationException, IllegalAccessException {
    /*
     * Instantiate a new object (must be AbstractCard or extend it, makes
     * sense for the CardsUI mechanic) from a Class descriptor.
     */
    AbstractCard newCard = model.cardClass.newInstance();
    Log.i("CardFactory", "Creating a new card! We're making a new " + model.cardClass.getName());

    /*
     * We will also need the Class descriptor for the object we just created
     * in order to access its fields.
     */
    Class<? extends AbstractCard> newCardClazz = newCard.getClass();

    /*
     * Java objects do not flatten their hierarchy at runtime (that's good),
     * which means that we actually need to collect all fields from all the
     * ancestors. Here, we collect them into a HashMap for convenience.
     */
    HashMap<String, Field> destinationFields = new HashMap<String, Field>();
    Class<?> clazzUnderInspection = newCardClazz;
    while (clazzUnderInspection != null) {
      /*
       * Get all fields for the current point in the hierarchy, and
       * collect them into the HashMap.
       */
      Field[] clazzFields = clazzUnderInspection.getDeclaredFields();
      for (int i = 0; i < clazzFields.length; i++) {
        Field f = clazzFields[i];
        destinationFields.put(f.getName(), f);
      }
      /*
       * Okay, now examine the ancestor (for java.lang.Object it is null,
       * which means the loop will exit).
       */
      clazzUnderInspection = clazzUnderInspection.getSuperclass();
    }

    /*
     * Obtain a list of fields within the model. As most of them match those
     * in AbstractCard, the card's content will be preserved. Since the
     * model inherits only from Object, all fields collected here will be
     * what we need.
     */
    Field[] sourceFields = model.getClass().getDeclaredFields();

    /*
     * Now iterate over the fields in the model.
     */
    for (int i = 0; i < sourceFields.length; i++) {
      // Just a reference for the field we're copying in this pass
      Field curField = sourceFields[i];

      /*
       * This is to prevent IllegalAccessExceptions when accessing the
       * field. Yes, this violates the visibility set by the field
       * declarations, but that's the whole point of this routine.
       */
      curField.setAccessible(true);

      String fieldName = curField.getName();

      Log.d("CardFactory", " > Now copying field: " + fieldName);

      Field destField = destinationFields.get(fieldName);

      if (destField != null) {
        /*
         * We need to get the specific field that matches the one in the
         * model and set it to the same value as the corresponding field
         * in the model.
         */
        destField.setAccessible(true); // "Trust me."
        destField.set(newCard, curField.get(model));
        Log.d(
            "CardFactory",
            String.format(
                " > Field %s (= %s) -> Field %s (=%s)",
                curField, curField.get(model), destField.getName(), destField.get(newCard)));
      } else {
        /*
         * We have encountered a field (CardModel.data,
         * CardModel.cardClass, ...) in the model that does not exist in
         * the view that can represent it, so we just skip it. Yes, this
         * breaks the "for loop is fixed" convention, but this really is
         * the easiest way.
         *
         * "Go to Next Iteration. Go directly to Next Iteration. Do not
         * pass Go. Do not collect $200."
         */
        Log.d(
            "CardFactory",
            String.format(
                " > Skipping over an unmapped Field %s/%s (= %s)",
                model.cardClass.getName(), curField, curField.get(model)));
      }
    }

    return newCard;
  }
Exemplo n.º 2
0
 public Game getGame() {
   return primary.getGame();
 }