【发布时间】：2018-05-23 23:21:06
【问题描述】：
所以我试图通过 StringBuffer 解析并将其放入字符串列表中，然后使用 listview 列出所有餐厅名称，但是我在将 StringBuffer 转换为 JsonObject 时遇到问题，因为每次我尝试 getAsJsonObject();功能我的应用程序崩溃任何人都可以帮助弄清楚为什么我不能将 StringBuffer 转换为 JsonObject 以及如何正确获取缓冲区以转换为 JSON 对象。 任何帮助表示赞赏。
String restaurantName;
JsonElement restaurantJSONElement;
JsonPrimitive restaurantJSONPrimitive;
JsonParser parser = new JsonParser();
// buffer is the StringBuffer read
JsonElement parentJSONElement = parser.parse(String.valueOf(buffer));
JsonObject parentJSONObject = parentJSONElement.getAsJsonObject();
//this is where is crashes I assume its because it cant convert the JsonElement to a JsonObject
JsonArray restaurantsJSONArray = (JsonArray) parentJSONObject.get("restaurants");
List<String> restaurantnamelist1 = new ArrayList<String>();
{
for (int i = 0; i < 1; i++) {
//get the element
restaurantJSONElement = ((JsonObject) restaurantsJSONArray.get(i)).get("restaurant");
//get the restaurant name
restaurantJSONPrimitive = ((JsonObject) restaurantJSONElement.getAsJsonObject()).getAsJsonPrimitive("name");
restaurantName = restaurantJSONPrimitive.getAsString();
restaurantnamelist1.add(restaurantName);
}
}
这就是 StringBuffer 包含的内容：
{
"results_found": 10573,
"results_start": 0,
"results_shown": 20,
"restaurants": [
{
"restaurant": {
"R": {
"res_id": 16795271
},
"apikey": "fa221c30c201daf8380ac435cedfebe9",
"id": "16795271",
"name": "Craigie On Main", //This is what I want to sort it by
"url": "https://www.zomato.com/boston/craigie-on-main-cambridge?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"location": {
"address": "853 Main St, Cambridge 02139",
"locality": "Central Square",
"city": "Boston",
"city_id": 289,
"latitude": "42.3634820000",
"longitude": "-71.0985660000",
"zipcode": "02139",
"country_id": 216,
"locality_verbose": "Central Square, Boston"
},
"switch_to_order_menu": 0,
"cuisines": "European, French",
"average_cost_for_two": 275,
"price_range": 4,
"currency": "$",
"offers": [],
"thumb": "https://b.zmtcdn.com/data/res_imagery/16795271_CHAIN_bd36a0893cde3f70ab4a67f1e086d5f5.jpg?fit=around%7C200%3A200&crop=200%3A200%3B%2A%2C%2A",
"user_rating": {
"aggregate_rating": "4.2",
"rating_text": "Very Good",
"rating_color": "5BA829",
"votes": "342"
},
"photos_url": "https://www.zomato.com/boston/craigie-on-main-cambridge/photos?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1#tabtop",
"menu_url": "https://www.zomato.com/boston/craigie-on-main-cambridge/menu?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1&openSwipeBox=menu&showMinimal=1#tabtop",
"featured_image": "https://b.zmtcdn.com/data/res_imagery/16795271_CHAIN_bd36a0893cde3f70ab4a67f1e086d5f5.jpg",
"has_online_delivery": 0,
"is_delivering_now": 0,
"deeplink": "zomato://restaurant/16795271",
"has_table_booking": 0,
"events_url": "https://www.zomato.com/boston/craigie-on-main-cambridge/events#tabtop?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"establishment_types": []
}
},
{
"restaurant": {
"R": {
"res_id": 16798941
},
"apikey": "fa221c30c201daf8380ac435cedfebe9",
"id": "16798941",
"name": "O Ya",
"url": "https://www.zomato.com/boston/o-ya-boston?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"location": {
"address": "9 East St, Boston 02111",
"locality": "Leather District",
"city": "Boston",
"city_id": 289,
"latitude": "42.3513170000",
"longitude": "-71.0570370000",
"zipcode": "02111",
"country_id": 216,
"locality_verbose": "Leather District, Boston"
},
"switch_to_order_menu": 0,
"cuisines": "Japanese, Sushi",
"average_cost_for_two": 275,
"price_range": 4,
"currency": "$",
"offers": [],
"thumb": "https://b.zmtcdn.com/data/res_imagery/16798941_CHAIN_d58be7a0f56ad4fbad498ba65b746a67.jpg?fit=around%7C200%3A200&crop=200%3A200%3B%2A%2C%2A",
"user_rating": {
"aggregate_rating": "4.3",
"rating_text": "Very Good",
"rating_color": "5BA829",
"votes": "192"
},
"photos_url": "https://www.zomato.com/boston/o-ya-boston/photos?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1#tabtop",
"menu_url": "https://www.zomato.com/boston/o-ya-boston/menu?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1&openSwipeBox=menu&showMinimal=1#tabtop",
"featured_image": "https://b.zmtcdn.com/data/res_imagery/16798941_CHAIN_d58be7a0f56ad4fbad498ba65b746a67.jpg?output-format=webp",
"has_online_delivery": 0,
"is_delivering_now": 0,
"deeplink": "zomato://restaurant/16798941",
"has_table_booking": 0,
"events_url": "https://www.zomato.com/boston/o-ya-boston/events#tabtop?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"establishment_types": []
}
},
{
"restaurant": {
"R": {
"res_id": 16798079
},
"apikey": "fa221c30c201daf8380ac435cedfebe9",
"id": "16798079",
"name": "Solea Restaurant and Tapas Bar",
"url": "https://www.zomato.com/boston/solea-restaurant-and-tapas-bar-waltham?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"location": {
"address": "388 Moody St, Waltham 02453",
"locality": "Waltham",
"city": "Boston",
"city_id": 289,
"latitude": "42.3695490000",
"longitude": "-71.2370130000",
"zipcode": "02453",
"country_id": 216,
"locality_verbose": "Waltham, Boston"
},
"switch_to_order_menu": 0,
"cuisines": "Spanish, Tapas",
"average_cost_for_two": 275,
"price_range": 4,
"currency": "$",
"offers": [],
"thumb": "",
"user_rating": {
"aggregate_rating": "4.2",
"rating_text": "Very Good",
"rating_color": "5BA829",
"votes": "303"
},
"photos_url": "https://www.zomato.com/boston/solea-restaurant-and-tapas-bar-waltham/photos?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1#tabtop",
"menu_url": "https://www.zomato.com/boston/solea-restaurant-and-tapas-bar-waltham/menu?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1&openSwipeBox=menu&showMinimal=1#tabtop",
"featured_image": "",
"has_online_delivery": 0,
"is_delivering_now": 0,
"deeplink": "zomato://restaurant/16798079",
"has_table_booking": 0,
"events_url": "https://www.zomato.com/boston/solea-restaurant-and-tapas-bar-waltham/events#tabtop?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"establishment_types": []
}
},
"restaurant": {
"R": {
"res_id": 16796139
},
"apikey": "fa221c30c201daf8380ac435cedfebe9",
"id": "16796139",
"name": "Harvest",
"url": "https://www.zomato.com/boston/harvest-cambridge?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"location": {
"address": "44 Brattle St, Cambridge 02138",
"locality": "Harvard Square",
"city": "Boston",
"city_id": 289,
"latitude": "42.3742680000",
"longitude": "-71.1219960000",
"zipcode": "02138",
"country_id": 216,
"locality_verbose": "Harvard Square, Boston"
},
"switch_to_order_menu": 0,
"cuisines": "American, Breakfast",
"average_cost_for_two": 275,
"price_range": 4,
"currency": "$",
"offers": [],
"thumb": "https://b.zmtcdn.com/data/res_imagery/16796139_RESTAURANT_4f9960714d6bd153a4571dd062c4ff45.jpg?fit=around%7C200%3A200&crop=200%3A200%3B%2A%2C%2A",
"user_rating": {
"aggregate_rating": "3.9",
"rating_text": "Good",
"rating_color": "9ACD32",
"votes": "190"
},
"photos_url": "https://www.zomato.com/boston/harvest-cambridge/photos?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1#tabtop",
"menu_url": "https://www.zomato.com/boston/harvest-cambridge/menu?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1&openSwipeBox=menu&showMinimal=1#tabtop",
"featured_image": "https://b.zmtcdn.com/data/res_imagery/16796139_RESTAURANT_4f9960714d6bd153a4571dd062c4ff45.jpg",
"has_online_delivery": 0,
"is_delivering_now": 0,
"deeplink": "zomato://restaurant/16796139",
"has_table_booking": 0,
"events_url": "https://www.zomato.com/boston/harvest-cambridge/events#tabtop?utm_source=api_basic_user&utm_medium=api&utm_campaign=v2.1",
"establishment_types": []
}
},
【问题讨论】：
-
我刚刚尝试了您的代码，但它并没有崩溃。 JsonArray 餐厅JSONArray 已成功填充。我确实更改了您的 StringBuffer，因为它不是有效的 json 字符串。在任何网站上检查 json 字符串的有效性，例如 json.parser.online.fr
-
我得到的错误是：尝试在空对象引用上调用虚拟方法
-
这个错误发生在 JsonElements 尝试做 restaurantJSONElement = ((JsonObject) restaurantJSONArray.get(i)).get("restaurant");不知道为什么我会得到这个，因为我从来没有将任何东西设置为 null
-
你把 StringBuffer 改成什么了？
-
每次我尝试放入一个示例 StringBuffer 时，它都会崩溃我不确定你做了什么让它工作，你能告诉我你使用了什么 StringBuffer 吗？
标签： android json parsing stringbuffer