我正在尝试解析网站新闻Feed中的json结果。然而格式似乎很奇怪。我试图将其转换为xml以进行仔细观察，但我不确定如何访问这些字段。请帮忙
编辑：我知道有不同的页面显示如何解析它，但到目前为止他们的解决方案对我不起作用。
编辑：这是我得到的错误
java.lang.NullPointerException：尝试在空对象引用上调用虚方法'org.json.JSONObject org.json.JSONObject.getJSONObject（java.lang.String）'
JSON结果（来自浏览器）
{
"responseData":{
"feed":{
"feedUrl":"http://www.abc.net.au/news/feed/51120/rss.xml",
"title":"Just In",
"link":"http://www.abc.net.au/news/justin/",
"author":"",
"description":"",
"type":"rss20",
"entries":[
{
"mediaGroups":[
{
"contents":[
{
"url":"http://www.abc.net.au/news/image/7388850-16x9-2150x1210.jpg",
"type":"image/jpeg",
"medium":"image",
"height":1210,
"width":2150,
"lang":"en-US",
"description":"New Zealand netball could actually benefit from its split from Australia. (Getty Images: Mead Norton)",
"thumbnails":[
{
"height":105,
"width":140,
"url":"http://www.abc.net.au/news/image/7388850-4x3-140x105.jpg"
}
]
},
{
"url":"http://www.abc.net.au/news/image/7388850-4x3-940x705.jpg",
"type":"image/jpeg",
"medium":"image",
"height":705,
"width":940,
"lang":"en-US",
"description":"New Zealand netball could actually benefit from its split from Australia. (Getty Images: Mead Norton)",
"thumbnails":[
{
"height":105,
"width":140,
"url":"http://www.abc.net.au/news/image/7388850-4x3-140x105.jpg"
}
]
}}]}}, "responseDetails": null, "responseStatus": 200}
JSON转换为XML以获得更好的视图
<root>
<responseData>
<feed>
<feedUrl>http://www.abc.net.au/news/feed/51120/rss.xml</feedUrl>
<title>Just In</title>
<link>http://www.abc.net.au/news/justin/</link>
<author></author>
<description></description>
<type>rss20</type>
<entries>
<mediaGroups>
<contents>
<url>http://www.abc.net.au/news/image/7388850-16x9-2150x1210.jpg</url>
<type>image/jpeg</type>
<medium>image</medium>
<height>1210</height>
<width>2150</width>
<lang>en-US</lang>
<description>New Zealand netball could actually benefit from its split from Australia. (Getty Images: Mead Norton)</description>
<thumbnails>
<height>105</height>
<width>140</width>
<url>http://www.abc.net.au/news/image/7388850-4x3-140x105.jpg</url>
</thumbnails>
</contents>
<contents>
<url>http://www.abc.net.au/news/image/7388850-4x3-940x705.jpg</url>
<type>image/jpeg</type>
<medium>image</medium>
<height>705</height>
<width>940</width>
<lang>en-US</lang>
<description>New Zealand netball could actually benefit from its split from Australia. (Getty Images: Mead Norton)</description>
<thumbnails>
<height>105</height>
<width>140</width>
<url>http://www.abc.net.au/news/image/7388850-4x3-140x105.jpg</url>
</thumbnails>
</contents>
<contents>
<url>http://www.abc.net.au/news/image/7388850-3x2-940x627.jpg</url>
<type>image/jpeg</type>
<medium>image</medium>
<isDefault>true</isDefault>
<height>627</height>
<width>940</width>
<lang>en-US</lang>
<description>New Zealand netball could actually benefit from its split from Australia. (Getty Images: Mead Norton)</description>
<thumbnails>
<height>105</height>
<width>140</width>
<url>http://www.abc.net.au/news/image/7388850-4x3-140x105.jpg</url>
</thumbnails>
</contents>
<contents>
<url>http://www.abc.net.au/news/image/7388850-3x4-940x1253.jpg</url>
<type>image/jpeg</type>
<medium>image</medium>
<height>1253</height>
<width>940</width>
<lang>en-US</lang>
<description>New Zealand netball could actually benefit from its split from Australia. (Getty Images: Mead Norton)</description>
<thumbnails>
<height>105</height>
<width>140</width>
<url>http://www.abc.net.au/news/image/7388850-4x3-140x105.jpg</url>
</thumbnails>
</contents>
<contents>
<url>http://www.abc.net.au/news/image/7388850-1x1-1400x1400.jpg</url>
<type>image/jpeg</type>
<medium>image</medium>
<height>1400</height>
<width>1400</width>
<lang>en-US</lang>
<description>New Zealand netball could actually benefit from its split from Australia. (Getty Images: Mead Norton)</description>
<thumbnails>
<height>105</height>
<width>140</width>
<url>http://www.abc.net.au/news/image/7388850-4x3-140x105.jpg</url>
</thumbnails>
</contents>
</mediaGroups>
<title>New Zealand netball to get stronger after trans-Tasman split</title>
<link>http://www.abc.net.au/news/2016-05-27/new-zealand-netball-to-get-stronger-after-trans-tasman-split/7454468</link>
<author>Brittany Carter</author>
<publishedDate>Thu, 26 May 2016 23:27:34 -0700</publishedDate>
<contentSnippet>New Zealand's netball split with Australia has many fearing the worst, but it could well prove a massive boost for the sport ...</contentSnippet>
<content>
<p>New Zealand's netball split with Australia has many fearing the worst, but it could well prove a massive boost for the sport across the ditch.</p>
</content>
<categories>Netball</categories>
<categories>Sport</categories>
</entries>
我想访问xml底部的作者，链接和其他元素，但不知道如何。这是我的安卓代码
try{
//instantiate json parser
JSONParser jsonParser = new JSONParser();
//get json string from the url
JSONObject jsonObject = jsonParser.getJSONFromURL(jsonURL);
Log.d("JSONOUT",jsonObject.getJSONObject("responseData").getJSONObject("feed").getString("feedUrl"));
}catch (JSONException e){
e.printStackTrace();
}
return null;
我的JSONParser类
public class JSONParser {
static InputStream is = null;
static JSONObject jsonObject = null;
static String json = "";
public JSONObject getJSONFromURL(String url){
//start HTTP Request
try{
DefaultHttpClient defaultHttpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse httpResponse = defaultHttpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}catch (UnsupportedEncodingException e){
e.printStackTrace();
}catch (ClientProtocolException e){
e.printStackTrace();
}catch (IOException e){
e.printStackTrace();
}
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while((line=reader.readLine())!=null){
sb.append(line + "\n");
}
is.close();
json = sb.toString();
Log.d("JSONRECEIVE",json);
}catch (UnsupportedEncodingException e){
e.printStackTrace();
}catch (IOException e){
e.printStackTrace();
}
//parse received String to a JSON object
try{
jsonObject = new JSONObject(json);
}catch (JSONException e){
e.printStackTrace();
}
//return the completed string
return jsonObject;
}
}