Android getJSONObject与optJSONObject的区别结合源码分析

//使用getJSONObject时,如果返回的对象不是JSONObject,抛出JSONException异常  /**   * Returns the value mapped by {@code name} if it exists and is a {@code   * JSONObject}.   * @throws JSONException if the mapping doesn't exist or is not a {@code   *   JSONObject}.   */  public JSONObject getJSONObject(String name) throws JSONException {    Object object = get(name);    if (object instanceof JSONObject) {      return (JSONObject) object;    } else {      throw JSON.typeMismatch(name, object, "JSONObject");    }  }//使用optJSONObject时,当返回结果不是JSONObject时,这里不会抛异常,而是返回null  /**   * Returns the value mapped by {@code name} if it exists and is a {@code   * JSONObject}. Returns null otherwise.   */  public JSONObject optJSONObject(String name) {    Object object = opt(name);    return object instanceof JSONObject ? (JSONObject) object : null;  }

 /**  * 伪代码如下  **/  public class GetGoodsCollectListFactory {    private String ERROR_MSG = "errorMsg";    private String ERROR_CODE = "errorCode";    private String RESULT   = "result";    /**     * 商品列表,解析获取到的json数据     *     * @param param     * @return     */    public CollectListInfo getGoodsCollectListParse(String param) {      String BOOK_MARK_BO_LIST = "favorGoodsList";      CollectListInfo collectList = new CollectListInfo();      List<CollectInfo> list = new ArrayList<CollectInfo>();      ResponseInfo responseInfo = null;      CollectInfo info = null;      try {        // 请求获取json结果        JSONObject jsonObject = new JSONObject(HttpRequestClient.executeRequest(Constant.Url.GET_FOLLOW_GOODS_URL, param, true));        responseInfo = new ResponseInfo();        if (jsonObject.getBoolean(RESULT)) {          responseInfo.setResult(true);          JSONArray jsonArray = jsonObject.getJSONArray(BOOK_MARK_BO_LIST);          collectList.setTotalPage(jsonObject.getInt(Constant.TOTAL_PAGE_NAME));          for (int i = 0; i < jsonArray.length(); i++) {            info = collectList.getCollectInfo();            SONObject object = jsonArray.getJSONObject(i);            JSONArray activityItemList = object.optJSONArray("activityItemList");            ArrayList<ActivityCollectInfo> activityCollectInfos = new ArrayList<ActivityCollectInfo>();            //因为object.optJSONArray("activityItemList");如果解析不到会直接返null            if (activityItemList != null && activityItemList.size() > 0) {              for (int j = 0; j < activityItemList.length(); j++) {                //使用optJSONObject(i)会莫名解析不了下面数据:如optString("activityId"));                // 当activityid为null时,不会抛错,但是下面的方法不走,因此换用getJSONObject(i);                //JSONObject activityItemobj = activityItemList.optJSONObject(i);                JSONObject activityItemobj = activityItemList.getJSONObject(i);                ActivityCollectInfo activityCollectInfo = new ActivityCollectInfo();                activityCollectInfo.setActivityId(activityItemobj.optString("activityId"));                activityCollectInfo.setActivityName(activityItemobj.optString("activityName"));                activityCollectInfo.setActivityType(activityItemobj.optInt("activityType"));                activityCollectInfo.setLargessFlag(activityItemobj.optInt("largessFlag"));                activityCollectInfo.setLargessMoney(activityItemobj.optInt("largessMoney"));                activityCollectInfo.setLargessNumber(activityItemobj.optInt("largessNumber"));                activityCollectInfos.add(activityCollectInfo);              } ...                        }        }