將數組列表轉換爲JSON

Question

我有一個android活動從servlet接收數組列表。示例[stl1010，P3]。當我嘗試將其轉換爲JSON對象（使用解析器類）時，我得到異常「解析數據org.json.JSONException時的錯誤：Value [」stl1010「，」P3「] org.json.JSONArray類型無法轉換到JSONObject「。下面是servlet代碼：

private ArrayList<String> ticketLookup(String tkt) 
    { 
    Connection con = null; 
    Statement st = null; 
    //StringArray msga = new StringArray(); 
    ArrayList<String> msga = new ArrayList(); 

    try 
    { 
     // These will vary depending on your server/database  
     Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); 
     con = DriverManager.getConnection("jdbc:sqlserver://serveripaddr;databaseName=dbname;user=sa;password=pwd"); 
     Statement stmt = con.createStatement(); 
     ResultSet rs = stmt.executeQuery("Select status,description,priority,openingdate,closeddate,assigned_to,resolvergroup,assigneddatel1,impactedbyuser,emailid from ServiceRequest where TicketNo = '"+tkt+"'"); 
while (rs.next()) 
     { 

//   rs.getString(2); 
      msga.add(String.valueOf(rs.getString("assigned_to"))); 
      msga.add(String.valueOf(rs.getString("priority"))); 
    } 
     //JSONArray mJSONArray = new JSONArray(Arrays.asList(mStringArray));  
     return msga; 

下面是我的Android應用程序代碼（JSON解析器類+活動）。活動代碼：

public void addListenerOnGoButton(){ 
btnGo.setOnClickListener(new OnClickListener() 

{ 
    public void onClick(View v) { 

     String url = "http://10.0.2.2:8080/GnP22/GetNpostServlet?TicketNo="+etTkt.getText(); 
     String TAG_TICKET = "ticket"; 
     String TAG_STATUS = "status"; 
     String TAG_DESC = "description"; 
     String TAG_PRIORITY = "priority"; 
     String TAG_OPENDATE = "openingdate"; 
     String TAG_CLOSEDATE = "closingdate"; 
     String TAG_ASSIGNEDTO = "assignedto"; 
     String TAG_RESOLVERGROUP = "resolvergroup"; 
     String TAG_ASSIGNEDDATEL1 = "assigneddatel1"; 
     String TAG_IMPACTEDUSER = "impactedbyuser"; 
     String TAG_EMAILID = "emailid"; 

     // contacts JSONArray 
     JSONArray contacts = null; 

     // Creating JSON Parser instance 
     JSONParser jParser = new JSONParser(); 

     // getting JSON string from URL 
     JSONObject json = jParser.getJSONFromUrl(url); 

     try { 
      // Getting Array of Contacts 
      contacts = json.getJSONArray(TAG_TICKET); 
      for(int i = 0; i < contacts.length(); i++){ 
      JSONObject c = contacts.getJSONObject(0); 

      String status = c.getString(TAG_STATUS); 
      String description = c.getString(TAG_DESC); 
      //String email = c.getString(TAG_EMAIL); 
      //String address = c.getString(TAG_ADDRESS); 
      //String gender = c.getString(TAG_GENDER); 
      tvStatus.setText(status); 
      tvDescription.setText(description); 
      } 
     } catch (JSONException e) { 
      //e.printStackTrace(); 
      Log.d("JSON Exception", e.toString()); 
     } 
} 
}); 

} 

下面是JSON解析器類代碼：

public class JSONParser { 

    static InputStream is = null; 
    static JSONObject jObj = null; 
    static String json = ""; 

// constructor 
    public JSONParser() { 

    } 

    public JSONObject getJSONFromUrl(String url) { 

     // Making HTTP request 
     try { 
      // defaultHttpClient 
      DefaultHttpClient httpClient = new DefaultHttpClient(); 
      //HttpPost httpPost = new HttpPost(url); 
      HttpGet httpPost = new HttpGet(url); 

      HttpResponse httpResponse = httpClient.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(); 
     } catch (Exception e) { 
      Log.e("Buffer Error", "Error converting result " + e.toString()); 
     } 

     // try parse the string to a JSON object 
     try { 
      jObj = new JSONObject(json); 
     } catch (JSONException e) { 
      Log.e("JSON Parser", "Error parsing data " + e.toString()); 
     } 

     // return JSON String 
     return jObj; 

    } 
} 

Answer 1

你得到的響應，其中，你試圖得到一個對象數組

更換

// getting JSON string from URL 
JSONObject json = jParser.getJSONFromUrl(url); 

到

JSONArray json = jParser.getJSONFromUrl(url); 

而且

public JSONObject getJSONFromUrl(String url) { 
    //This returns a JSONObject Modify this to return JSONArray 
}