我想解析这个 xml api:http ://gdata.youtube.com/feeds/api/videos?max-results=50&q=honey 我正在把这个 api 的响应变成一个字符串,然后使用 sax 解析器解析它. 但是我在 parse 语句中得到空异常。
代码:
protected void onPostExecute(String result)
{
super.onPostExecute(result);
try {
xr.parse(result); //null exception
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SAXException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
编辑:对不起,这是完整的代码:
public class MainActivity extends Activity implements OnClickListener {
static final String baseURL = "http://gdata.youtube.com/feeds/api/videos?max-results=50&q=";
static boolean flag=false;
EditText enter;
String tmp;
TextView label;
Button calc;
ListView lv;
listadapter la;
String arr[];
SAXParserFactory spf;
SAXParser sp;
XMLReader xr;
int index;
HandlingXMLStuff hxs;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.weatherxmlparse);
enter = (EditText) findViewById(R.id.editcity);
calc = (Button) findViewById(R.id.temp);
lv = (ListView) findViewById(R.id.list);
try {
hxs=new HandlingXMLStuff();
spf = SAXParserFactory.newInstance();
sp = spf.newSAXParser();
xr = sp.getXMLReader();
xr.setContentHandler(hxs);
} catch (Exception e) {
}
calc.setOnClickListener(this);
}
@Override
public void onClick(View arg0) {
arr=new String[50];
index=0;
flag=false;
Hashtable<String, String> hs = new Hashtable<String, String>();
hs.put("", "");
new getVideos().execute(hs);
// la = new listadapter(this, arr);
// lv.setAdapter(la);
// } catch (Exception e) {
// }
}
public class HandlingXMLStuff extends DefaultHandler {
public String getInformation() {
return "";
}
@Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
// TODO Auto-generated method stub
if (localName.equals("id")) {
if(!flag)
flag=true;
else
{
String temp="";
String temp2=temp.replaceAll("http://gdata.youtube.com/feeds/api/videos/","");
}
}
}
}
class getVideos extends
AsyncTask<Hashtable<String, String>, String, String> {
String resp = "";
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(Hashtable<String, String>... prmss) {
StringBuilder URL = new StringBuilder(baseURL);
String fullURL = URL.toString();
try {
///String q = URLEncoder.encode(fullURL+enter.getText().toString(), "utf-8");
Hashtable<String,String> params=new Hashtable<String,String>();
params.put("","");
URL website = new URL(baseURL+enter.getText().toString());
String query = URLEncoder.encode(baseURL+enter.getText().toString(), "utf-8");
resp = ServerCom.getWeb(baseURL+enter.getText().toString(), params);
tmp=resp;
//bugged............
} catch (Exception e) {
e.printStackTrace();
return resp;
}
return resp;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
try {
xr.parse(result);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SAXException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
忽略 ServerCom 类,因为它正在正确返回响应。
服务器通讯:
public class ServerCom
{
public static String getWeb(String Url , Hashtable<String, String> params) throws Exception
{
String resp = callWebService(HttpGet.METHOD_NAME, Url, params);
return resp;
}
public static String callWebService(String httpMethod, String URL,
Hashtable<String, String> params) throws Exception {
String sResponse = "";
String resp = "";
try
{
Enumeration<String> e = params.elements();
e = params.keys();
HttpClient httpClient = new DefaultHttpClient();
HttpPost postRequest = new HttpPost(URL);
HttpGet getRequest = new HttpGet(URL);
MultipartEntity reqEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
HttpResponse response;
if (httpMethod.equalsIgnoreCase(HttpPost.METHOD_NAME)) {
while (e.hasMoreElements()) {
String key = (String) e.nextElement();
String value = (String) params.get(key);
reqEntity.addPart(key, new StringBody(value));
}
postRequest.setEntity(reqEntity);
// postRequest.setEntity(reqEntityForFile);
response = httpClient.execute(postRequest);
} else
{
HttpParams httpParams = new BasicHttpParams();
while (e.hasMoreElements()) {
String key = (String) e.nextElement();
String value = (String) params.get(key);
// reqEntity.addPart(key, new StringBody(value));
httpParams.setParameter(key, value);
}
getRequest.setParams(httpParams);
response = httpClient.execute(getRequest);
}
BufferedReader reader = new BufferedReader(
new InputStreamReader(
response.getEntity().getContent(), "UTF-8"));
StringBuilder s = new StringBuilder();
while ((sResponse = reader.readLine()) != null) {
s = s.append(sResponse);
resp = resp.concat(sResponse);
}
} catch (Exception e) {
Log.e(e.getClass().getName(), e.getMessage());
}
Log.v("Im Coming app", "Response: " + resp);
return resp;
}
}
编辑:
日志猫:http : //pastie.org/8383635