关于getJSONObject与optJSONObject的区别？

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*json解析常见问题:

getJSONObject与optJSONObject的区别,下面结合源码和案例来分析当我们使用这两周方法来解析数据时,哪种比较好.
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);                            } ...                                               }                }

此篇文章是转载别人的一篇文章，仅用于收集

http://blog.csdn.net/relicemxd/article/details/50351094

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