无法解析此JSON数组.具有子阵列和对象我想要解析的

Question

JSON。我想要解析的两个JSON数据。我的主要Activty代码已经提供，请看一下。我已经访问了JSON数组，并在上面循环获取第一个元素的Object，并试图从第一个元素中获取详细信息，不幸的是，我无法获取它们。我试图记录从postExecute返回的arrayListed。它仍然显示大小=0.

[
{
"score": 24.910917,
"show": {
"id": 13,
"url": "http://www.tvmaze.com/shows/13/the-flash",
"name": "The Flash",
"type": "Scripted",
"language": "English",
"genres": [
"Drama",
"Action",
"Science-Fiction"
],
"status": "Running",
"runtime": 60,
"premiered": "2014-10-07",
"officialSite": "http://www.cwtv.com/shows/the-flash/",
"schedule": {
"time": "20:00",
"days": [
"Tuesday"
]
},
"rating": {
"average": 8.1
},
"weight": 99,
"network": {
"id": 5,
"name": "The CW",
"country": {
"name": "United States",
"code": "US",
"timezone": "America/New_York"
}
},
"webChannel": null,
"externals": {
"tvrage": 36939,
"thetvdb": 279121,
"imdb": "tt3107288"
},
"image": {
"medium": "http://static.tvmaze.com/uploads/images/medium_portrait/129/323466.jpg",
"original": "http://static.tvmaze.com/uploads/images/original_untouched/129/323466.jpg"
},
"summary": "<p>After a particle accelerator causes a freak storm, CSI Investigator Barry Allen is struck by lightning and falls into a coma. Months later he awakens with the power of super speed, granting him the ability to move through Central City like an unseen guardian angel. Though initially excited by his newfound powers, Barry is shocked to discover he is not the only "meta-human" who was created in the wake of the accelerator explosion -- and not everyone is using their new powers for good. Barry partners with S.T.A.R. Labs and dedicates his life to protect the innocent. For now, only a few close friends and associates know that Barry is literally the fastest man alive, but it won't be long before the world learns what Barry Allen has become...The Flash!</p>",
"updated": 1532242720,
"_links": {
"self": {
"href": "http://api.tvmaze.com/shows/13"
},
"previousepisode": {
"href": "http://api.tvmaze.com/episodes/1426878"
},
"nextepisode": {
"href": "http://api.tvmaze.com/episodes/1473791"
}
}
}
},
{
"score": 22.392826,
"show": {
"id": 528,
"url": "http://www.tvmaze.com/shows/528/the-flash",
"name": "The Flash",
"type": "Scripted",
"language": "English",
"genres": [
"Action",
"Adventure",
"Science-Fiction"
],
"status": "Ended",
"runtime": 60,
"premiered": "1990-09-20",
"officialSite": null,
"schedule": {
"time": "20:30",
"days": [
]
},
"rating": {
"average": 8.6
},
"weight": 71,
"network": {
"id": 2,
"name": "CBS",
"country": {
"name": "United States",
"code": "US",
"timezone": "America/New_York"
}
},
"webChannel": null,
"externals": {
"tvrage": 5781,
"thetvdb": 78650,
"imdb": "tt0098798"
},
"image": {
"medium": "http://static.tvmaze.com/uploads/images/medium_portrait/4/11360.jpg",
"original": "http://static.tvmaze.com/uploads/images/original_untouched/4/11360.jpg"
},
"summary": "<p>The Flash is Barry Allen, a police scientist, who was working one night during a terrible thunder storm when a bolt of lightning crashes through the lab window, electrocuting him. Barry survives and soon learns that he is now able to move at almost incomprehensible speed.</p>",
"updated": 1509496066,
"_links": {
"self": {
"href": "http://api.tvmaze.com/shows/528"
},
"previousepisode": {
"href": "http://api.tvmaze.com/episodes/47947"
}
}
}
},

主要活动

package com.vineet.moviesapp;
import android.net.Uri;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Scanner;
public class MainActivity extends AppCompatActivity {
private static final String TAG = "LOG MESSAGE";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btnGet = findViewById(R.id.btnGet);
btnGet.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
updateTextView();
}
});
}

public void updateTextView(){
NetworkTask networkTask = new NetworkTask();
networkTask.execute("https://api.tvmaze.com/search/shows?q=flash");
}
class NetworkTask extends AsyncTask<String, Void, String>{
@Override
protected String doInBackground(String... strings) {
String stringUrl = strings[0];
try {
URL url = new URL(stringUrl);
HttpURLConnection httpURLConnection= (HttpURLConnection) url.openConnection();
InputStream inputStream = httpURLConnection.getInputStream();
Scanner scanner = new Scanner(inputStream);
scanner.useDelimiter("\A");
if (scanner.hasNext()){
String s = scanner.next();
return s;
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
ArrayList<Movie> movieArrayList = parseJson(s);
Log.d(TAG,"onPostExec"+ movieArrayList.size());
}
}
ArrayList<Movie> parseJson(String s){
ArrayList<Movie> movies = new ArrayList<>();
try {
JSONArray root = new JSONArray(s);
for(int i=0; i<root.length(); i++){
JSONObject object = root.getJSONObject(i);
Integer score = object.getInt("score");
String name = object.getJSONObject("show").getString("name");
String language = object.getJSONObject("show").getString("language");
String image = object.getJSONObject("show").getJSONObject("image").getString("medium");
Double rating = object.getJSONObject("show").getDouble("average");
Movie movie = new Movie(score,name,language,image,rating);
movies.add(movie);
}
} catch (JSONException e) {
e.printStackTrace();
}
return movies;
}
}

我试着用自己的方式分析数据。但无法解析。请帮助我，让我知道我在哪里犯了错误。

Answer 1

乍一看可能是这个

Integer score = object.getInt("score");

因为json中的分数是"score"：24.910917。这是一个双
也在此行中

Double rating = object.getJSONObject("show").getDouble("average");

json是

"rating": {
"average": 8.1
},

所以应该是

Double rating = object.getJSONObject("show").getJSONObject("rating").getDouble("average");

Answer 2

不想分散Tomer Shemesh的注意力，但如果您无法控制正在访问的API，那么我建议您使用opt方法来访问JSON字符串中的值。opt方法提供了在密钥由于某种原因不可用时添加可选值的能力。例如，你可以试试这个：

JSONArray root = new JSONArray(s);
for(int i=0; i<root.length(); i++){
JSONObject object = root.getJSONObject(i);
Double score = object.optDouble("score", -1);
JSONObject showObject = object.getJSONObject("show");
String name = showObject.optString("name", "Name NA");
String language = showObject.optString("language", "Language NA");
JSONObject imageObject = showObject.getJSONObject("image");
String image = imageObject.optString("medium", "Image Medium NA");
JSONObject ratingObject = showObject.getJSONObject("rating");
Double rating = ratingObject.optDouble("average", -1);
Movie movie = new Movie(score,name,language,image,rating);
movies.add(movie);
}

例如，请注意，如果密钥"name"不可用，showObject.optString("name", "Name NA");会为您提供一个可选值——如果它不存在，则会得到字符串"name NA"，而不会导致错误。同样，如果密钥"average"不可用，ratingObject.optDouble("average", -1);将返回"-1"。

示例：如果您只使用getString("name");' and the "name" key is not present in the JSON string, then you will get an error and the loop will stop. If however, you haveoptString("name"，"NA"(；'并且JSON字符串中不存在"name"键，则会得到"NA"，循环将继续。