1.将json格式的字符串{}转化为JAVA对象
//第一步：获取或创建Json数据
String json = "{\n" +
" \"id\":2,\"name\":\"小龙虾\",\n" +
" \"price\":12.3,\n" +
" \"imagePath\":\"https://192.168.10.165:8080/L05 Server/images/f1.jpg\"\n" +
" }";
//第二步：解析json数据
try {
//JSONObject(json)将json字符串解析为json对象
JSONObject jsonObject = new JSONObject(json);
//optXXX方法会在对应的key中的值不存在的时候返回一个空字符串或者返回你指定的默认值
//但是getString方法会出现空指针异常的错误
//int id = jsonObject.getInt("id");
int id1 = jsonObject.optInt("id");
String name = jsonObject.optString("name");
double price = jsonObject.optDouble("price");
String imagePath = jsonObject.optString("imagePath");
shopBean = new ShopBean(id1, name, price, imagePath);//封装java对象
} catch (JSONException e) {
e.printStackTrace();
}
//第三步：显示数据
tv_native_original.setText(json);//显示原始数据
tv_native_last.setText(shopBean.toString());//转换后数据2.将json格式的字符串[]转化为JAVA对象的List
//第一步：获取或创建Json数据
String json = "[\n" +
" {\n" +
" \"id\":1,\n" +
" \"name\":\"小龙虾1\",\n" +
" \"price\":12.3,\n" +
" \"imagePath\":\"https://192.168.10.165:8080/f1.jpg\"\n" +
" },\n" +
" {\n" +
" \"id\":2,\n" +
" \"name\":\"小龙虾2\",\n" +
" \"price\":22.3,\n" +
" \"imagePath\":\"https://192.168.10.165:8080/f2.jpg\"\n" +
" },\n" +
"]";
//第二步：解析json数据
List<ShopBean> list = new ArrayList<>();
try {
JSONArray jsonArray = new JSONArray(json);
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
if (jsonObject != null){
int id = jsonObject.optInt("id");
String name = jsonObject.optString("name");
double price = jsonObject.optDouble("price");
String imagePath = jsonObject.optString("imagePath");
shopBean = new ShopBean(id,name,price,imagePath);
list.add(shopBean);
}
}
} catch (JSONException e) {
e.printStackTrace();
}
//第三步：显示数据
tv_native_original.setText(json);//显示原始数据
tv_native_last.setText(list.toString());//转换后数据3.复杂json数据的解析
//第一步：获取或创建Json数据
String json = "{\n" +
" \"data\":{\n" +
" \"count\":5,\n" +
" \"items\":[\n" +
" {\n" +
" \"id\":45,\n" +
" \"title\":\"坚果\"\n" +
" },\n" +
" {\n" +
" \"id\":46,\n" +
" \"title\":\"炒货\"\n" +
" }\n" +
" ]\n" +
" },\n" +
" \"rs_code\":\"1000\",\n" +
" \"rs_msg\":\"success\"\n" +
"}";
//封装Java对象
DataInfo dataInfo = new DataInfo();
//第二步：解析json数据
try {
JSONObject jsonObject = new JSONObject(json);
//第一层解析
JSONObject object = jsonObject.optJSONObject("data");
String rs_code = jsonObject.optString("rs_code");
String rs_msg = jsonObject.optString("rs_msg");
//第一层封装
dataInfo.setRs_code(rs_code);
dataInfo.setRs_msg(rs_msg);
DataInfo.DataDTO dataBean = new DataInfo.DataDTO();
dataInfo.setData(dataBean);
//第二层解析
int count = object.optInt("count");
JSONArray items = object.optJSONArray("items");
//第二层数据的封装
dataBean.setCount(count);
List<DataInfo.DataDTO.ItemsDTO> itemsBean = new ArrayList<>();
dataBean.setItems(itemsBean);
//第三层解析
for (int i = 0; i < items.length(); i++) {
if (items != null){
JSONObject jsonObject1 = items.optJSONObject(i);
int id = jsonObject1.optInt("id");
String title = jsonObject1.optString("title");
//第三层数据的封装
DataInfo.DataDTO.ItemsDTO itemsDTO = new DataInfo.DataDTO.ItemsDTO();
itemsDTO.setId(id);
itemsDTO.setTitle(title);
itemsBean.add(itemsDTO);
}
}
} catch (JSONException e) {
e.printStackTrace();
}
//第三步：显示数据
tv_native_original.setText(json);
tv_native_last.setText(dataInfo.toString());4.特殊json数据解析
//第一步：获取或创建Json数据
String json = "{\n" +
" \"code\":0,\n" +
" \"list\":{\n" +
" \"0\":{\n" +
" \"aid\":\"8900789\",\n" +
" \"author\":\"春江水暖鸭先知\",\n" +
" \"coins\":188,\n" +
" \"copyright\":\"Copy\",\n" +
" \"create\":\"2022-04-11 16:30\"\n" +
" },\n" +
" \"1\":{\n" +
" \"aid\":\"8900788\",\n" +
" \"author\":\"清明时节雨纷纷\",\n" +
" \"coins\":189,\n" +
" \"copyright\":\"Copy\",\n" +
" \"create\":\"2022-04-11 16:40\" \n" +
" }\n" +
" }\n" +
"}";
//创建封装的java对象
FilmInfo filmInfo = new FilmInfo();
//第二步：解析json数据
try {
JSONObject jsonObject = new JSONObject(json);
//第一层解析
int code = jsonObject.optInt("code");
JSONObject list = jsonObject.optJSONObject("list");
//第一层封装
filmInfo.setCode(code);
List<FilmInfo.FilmBean> lists = new ArrayList<>();
filmInfo.setList(lists);
//第二层解析
for (int i = 0; i < list.length(); i++) {
JSONObject jsonObject1 = list.optJSONObject(i + "");
if (jsonObject1 != null){
String aid = jsonObject1.optString("aid");
String author = jsonObject1.optString("author");
int coins = jsonObject1.optInt("coins");
String copyright = jsonObject1.optString("copyright");
String create = jsonObject1.optString("create");
//第二层数据封装
FilmInfo.FilmBean filmBean = new FilmInfo.FilmBean();
filmBean.setAid(aid);
filmBean.setAuthor(author);
filmBean.setCoins(coins);
filmBean.setCopyright(copyright);
filmBean.setCreate(create);
lists.add(filmBean);
}
}
} catch (JSONException e) {
e.printStackTrace();
}
//第三步：显示数据
tv_native_original.setText(json);
tv_native_last.setText(filmInfo.toString());完整demoXizhongName/JSON (github.com)
https://github.com/XiZhongName/JSON
