JSON解析错误（Android）

我对Android开发相当陌生，我正试图编写一个程序来解析网站上的一些JSON，并将其输出到ListView中。然而，当我运行我的程序时，我得到了错误：

05-24 05:37:41.524: E/JSON Parser(783): Error parsing data org.json.JSONException: Value <?xml of type java.lang.String cannot be converted to JSONArray

我知道，空格很糟糕，但这是一个我无法改变的外部来源

我的代码：

从主要活动中：

public class AndroidJSONParsingActivity extends ListActivity {

private static String url = "http://redsox.tcs.auckland.ac.nz/734A/CSService.svc/courses";

private static final String TAG_CODE = "codeField";
private static final String TAG_SEMESTER = "semesterField";
private static final String TAG_TITLE = "titleField";

JSONArray courses = null;

    @Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    // Hashmap for ListView
    ArrayList<HashMap<String, String>> courseList = new ArrayList<HashMap<String, String>>();

    JSONParser jParser = new JSONParser();
    courses = jParser.getJSONfromURL(url);

    try {
        for(int i = 0; i < courses.length(); i++){
            JSONObject c = courses.getJSONObject(i);

            // Storing each json item in variable
            String code = c.getString(TAG_CODE);
            String semester = c.getString(TAG_SEMESTER);
            String title = c.getString(TAG_TITLE);

            // creating new HashMap
            HashMap<String, String> map = new HashMap<String, String>();

            // adding each child node to HashMap key => value
            map.put(TAG_CODE, code);
            map.put(TAG_SEMESTER, semester);
            map.put(TAG_TITLE, title);

            // adding HashList to ArrayList
            courseList.add(map);
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }


    //Updating parsed JSON data into ListView
    ListAdapter adapter = new SimpleAdapter(this, courseList,
            R.layout.list_item,
            new String[] { TAG_CODE, TAG_SEMESTER, TAG_TITLE }, new int[] {
                    R.id.code, R.id.semester, R.id.title });

    setListAdapter(adapter);

编辑：完整日志目录为：

05-24 06:48:55.347: D/dalvikvm(787): GC_CONCURRENT freed 68K, 8% free 2736K/2948K, paused 6ms+34ms, total 115ms
05-24 06:48:55.547: E/JSON Parser(787): Error parsing data org.json.JSONException: Value <?xml of type java.lang.String cannot be converted to JSONArray
05-24 06:48:55.547: D/AndroidRuntime(787): Shutting down VM
05-24 06:48:55.547: W/dalvikvm(787): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
05-24 06:48:55.577: E/AndroidRuntime(787): FATAL EXCEPTION: main
05-24 06:48:55.577: E/AndroidRuntime(787): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.androidhive.jsonparsing/com.androidhive.jsonparsing.AndroidJSONParsingActivity}: java.lang.NullPointerException
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.ActivityThread.access$600(ActivityThread.java:141)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.os.Looper.loop(Looper.java:137)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.ActivityThread.main(ActivityThread.java:5041)
05-24 06:48:55.577: E/AndroidRuntime(787):  at java.lang.reflect.Method.invokeNative(Native Method)
05-24 06:48:55.577: E/AndroidRuntime(787):  at java.lang.reflect.Method.invoke(Method.java:511)
05-24 06:48:55.577: E/AndroidRuntime(787):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-24 06:48:55.577: E/AndroidRuntime(787):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-24 06:48:55.577: E/AndroidRuntime(787):  at dalvik.system.NativeStart.main(Native Method)
05-24 06:48:55.577: E/AndroidRuntime(787): Caused by: java.lang.NullPointerException
05-24 06:48:55.577: E/AndroidRuntime(787):  at com.androidhive.jsonparsing.AndroidJSONParsingActivity.onCreate(AndroidJSONParsingActivity.java:44)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.Activity.performCreate(Activity.java:5104)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
05-24 06:48:55.577: E/AndroidRuntime(787):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
05-24 06:48:55.577: E/AndroidRuntime(787):  ... 11 more

05-24 06:48:55.347:D/dalvikvm（787）：GC_并发释放68K，8%释放2736K/2948K，暂停6ms+34ms，总计115ms
05-24 06:48:55.547:E/JSON解析器（787）：解析数据org.JSON.JSONException时出错：Value您仅在JSON解析器类中创建JSON数组。然后尝试获取一个json对象。
试一试

对于json解析器类，当您（在运行时）获取它时，如下所示：

 class LoadAllProducts extends AsyncTask<String, String, String> {
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(ProductsView.this);
        pDialog.setMessage(resStrings.get(0));
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }

    @Override
    protected String doInBackground(String... params) {
        List<NameValuePair> params1 = new ArrayList<NameValuePair>();
        JSONObject json = jParser.makeHttpRequest(UrlList.url_all_products, "GET", params1);
        Log.d(resStrings.get(1), json.toString());
        int success = 0;
        try {
            success = json.getInt(TagList.TAG_SUCCESS);
            if (success == 1) {
                final JSONArray products = json.getJSONArray(TagList.TAG_PRODUCTS);
                for (int i = 0; i < products.length(); i++) {
                    JSONObject c = products.getJSONObject(i);
                    String id = c.getString(TagList.TAG_PID);
                    String name = c.getString(TagList.TAG_PNAME);
                    String quantity = c.getString(TagList.TAG_PQUANTITY);
                    String price = c.getString(TagList.TAG_PPRICE);
                    String mod = c.getString(TagList.TAG_PMOD);

                    HashMap<String, String> map = new HashMap<String, String>();
                    map.put(TagList.TAG_PID, id);
                    map.put(TagList.TAG_PNAME, name);
                    map.put(TagList.TAG_PMOD, mod);
                    map.put(TagList.TAG_PQUANTITY, quantity);
                    map.put(TagList.TAG_PPRICE, price);
                    productsList.add(map);
                }
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(String file_url) {
        pDialog.dismiss();
       runOnUiThread(new Runnable() {
          @Override
        public void run() {
                ListAdapter adapter = new SimpleAdapter(ProductsView.this, productsList, R.layout.list_item,  new String[] { TagList.TAG_PID, TagList.TAG_PNAME, TagList.TAG_PMOD, TagList.TAG_PQUANTITY, TagList.TAG_PPRICE }, new int[] { R.id.pid, R.id.pname, R.id.pmod, R.id.pquantity, R.id.pprice });
                setListAdapter(adapter);
                setProductList();
          }
       });
    }

walls = TileMapFactory.buildMap(tileMap);
        for (int i = 0; i < walls.size(); i++) {
            mWorldMap[walls.get(i).x][walls.get(i).y].setType(Tile.TYPE_WALL);
        }

然后是一个阶级工厂

public class TileMapFactory {

public static ArrayList<Point> buildMap(final String tileMapJson) throws JSONException {

    ArrayList<Point> points = new ArrayList<Point>();

    final JSONObject jObject = new JSONObject(tileMapJson);
    final JSONArray jWalls = jObject.getJSONArray("walls");

    for (int i = 0; i < jWalls.length(); i++) {
        final JSONArray jWall = jWalls.getJSONArray(i);
        points.add(new Point((Integer) jWall.get(0), (Integer) jWall.get(1)));
    }

    return points;
}

公共类TileMapFactory{
公共静态ArrayList构建映射（最终字符串tileMapJson）抛出JSONException{
ArrayList points=新的ArrayList（）；
最终JSONObject jObject=新JSONObject（tileMapJson）；
final JSONArray jWalls=jObject.getJSONArray（“墙”）；
对于（int i=0；i

}

然后您可以像这样访问字符串：

 class LoadAllProducts extends AsyncTask<String, String, String> {
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(ProductsView.this);
        pDialog.setMessage(resStrings.get(0));
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }

    @Override
    protected String doInBackground(String... params) {
        List<NameValuePair> params1 = new ArrayList<NameValuePair>();
        JSONObject json = jParser.makeHttpRequest(UrlList.url_all_products, "GET", params1);
        Log.d(resStrings.get(1), json.toString());
        int success = 0;
        try {
            success = json.getInt(TagList.TAG_SUCCESS);
            if (success == 1) {
                final JSONArray products = json.getJSONArray(TagList.TAG_PRODUCTS);
                for (int i = 0; i < products.length(); i++) {
                    JSONObject c = products.getJSONObject(i);
                    String id = c.getString(TagList.TAG_PID);
                    String name = c.getString(TagList.TAG_PNAME);
                    String quantity = c.getString(TagList.TAG_PQUANTITY);
                    String price = c.getString(TagList.TAG_PPRICE);
                    String mod = c.getString(TagList.TAG_PMOD);

                    HashMap<String, String> map = new HashMap<String, String>();
                    map.put(TagList.TAG_PID, id);
                    map.put(TagList.TAG_PNAME, name);
                    map.put(TagList.TAG_PMOD, mod);
                    map.put(TagList.TAG_PQUANTITY, quantity);
                    map.put(TagList.TAG_PPRICE, price);
                    productsList.add(map);
                }
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(String file_url) {
        pDialog.dismiss();
       runOnUiThread(new Runnable() {
          @Override
        public void run() {
                ListAdapter adapter = new SimpleAdapter(ProductsView.this, productsList, R.layout.list_item,  new String[] { TagList.TAG_PID, TagList.TAG_PNAME, TagList.TAG_PMOD, TagList.TAG_PQUANTITY, TagList.TAG_PPRICE }, new int[] { R.id.pid, R.id.pname, R.id.pmod, R.id.pquantity, R.id.pprice });
                setListAdapter(adapter);
                setProductList();
          }
       });
    }

walls = TileMapFactory.buildMap(tileMap);
        for (int i = 0; i < walls.size(); i++) {
            mWorldMap[walls.get(i).x][walls.get(i).y].setType(Tile.TYPE_WALL);
        }

walls=TileMapFactory.buildMap（tileMap）；
对于（int i=0；i

在本例中，walls字符串为空，但当您将wall标记替换为CharDebious时，将有一个由2个字符串组成的数组。然后，您可以通过调用例如walls.get（i）来访问类似于arraylist的字符串；在你的例子中，比如codeField。
添加新行会弄乱你的json字符串。

尝试更改
sb.append（行+“\n”）添加到
某人（行）“\n”
会弄乱您的字符串。

否则，您的代码看起来很好。我建议您在您的案例中使用
AsyncTask
task

    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); // escape will mess up your json string
        }
        is.close();
        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

Alhumdulillah.我终于解决了你的问题

您正在对此url发出
POST
请求，但这是不允许的。您应该将HTTP请求更改为键入
GET

去

并与邮政局核对并获取

在您收到此回复的帖子中：

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <title>Service</title>
    <style>BODY { color: #000000; background-color: white; font-family: Verdana; margin-left: 0px; margin-top: 0px; } #content { margin-left: 30px; font-size: .70em; padding-bottom: 2em; } A:link { color: #336699; font-weight: bold; text-decoration: underline; } A:visited { color: #6699cc; font-weight: bold; text-decoration: underline; } A:active { color: #336699; font-weight: bold; text-decoration: underline; } .heading1 { background-color: #003366; border-bottom: #336699 6px solid; color: #ffffff; font-family: Tahoma; font-size: 26px; font-weight: normal;margin: 0em 0em 10px -20px; padding-bottom: 8px; padding-left: 30px;padding-top: 16px;} pre { font-size:small; background-color: #e5e5cc; padding: 5px; font-family: Courier New; margin-top: 0px; border: 1px #f0f0e0 solid; white-space: pre-wrap; white-space: -pre-wrap; word-wrap: break-word; } table { border-collapse: collapse; border-spacing: 0px; font-family: Verdana;} table th { border-right: 2px white solid; border-bottom: 2px white solid; font-weight: bold; background-color: #cecf9c;} table td { border-right: 2px white solid; border-bottom: 2px white solid; background-color: #e5e5cc;}</style>
  </head>
  <body>
    <div id="content">
      <p class="heading1">Service</p>
      <p xmlns="">Method not allowed. Please see the <a rel="help-page" href="http://redsox.tcs.auckland.ac.nz/734A/CSService.svc/help">service help page</a> for constructing valid requests to the service.</p>
    </div>
  </body>
</html>


服务
正文{color:#000000；背景色：白色；字体系列：Verdana；左边距：0px；右边距：0px；}内容{35;左边距：30px；字体大小：70em；底部填充：2em；}A:链接{color:#336699；字体重量：粗体；文本装饰：下划线；}A:已访问{color:#6699cc；字体重量：粗体；文本装饰：下划线；}A:活动{颜色：#336699；字体大小：粗体；文本装饰：下划线；}。标题1{背景颜色：#003366；边框底部：#336699 6px实心；颜色：#FFFFFFFF；字体系列：Tahoma；字体大小：26px；字体大小：正常；边距：0em 0em 10px-20px；填充底部：8px；填充左侧：30px；填充顶部：16px；}预处理{字体大小：小；背景色：#e5e5cc；填充：5px；字体系列：Courier New；页边距顶端：0px；边框：1px#f0f0e0实心；空白：预换行；空白：-预换行；字换行：中断字；}表格{边框折叠：折叠；边框间距：0px；字体系列：Verdana；}表格th{右边框：2px白色实心；边框底部：2px白色实心；字体大小：粗体；背景色：#cecf9c；}表格td{右边框：2px白色实心；边框底部：2px白色实心；背景色：#e5e5cc；}
服务
方法不允许。请参阅用于构造对服务的有效请求的

这就是为什么你会犯这样的错误

因此，您可以允许从服务器发送POST，也可以在
JSONParser
类中做一些更改，将
HttpPost
更改为
HttpGet
，现在就可以了。谢谢大家。：）我只是在GSON中使用了这些方法，非常简单。感谢大家的帮助

是的，HttpPost也应该是一个HttpGet。
你试图获取的url是什么？你上面给出的JSON响应不是完整的，也不是你从web上得到的准确响应。我100%确定它包含在标记中。在这里发布完整的响应。@PareshMayani。虽然我删除了答案，但人们也应该质疑原因e实际上是用来聊天的问题！！@PareshMayani我如何从网络上得到完整准确的回答？你是指我的日志吗？我将编辑我的帖子以包含它。@Nezam我将编辑我的帖子以包含我的代码中使用的URL Frank，看起来你的JSON在第一个节点中有“products”？我的帖子立即以[{“codeField”开头：“COMPSCI 101”…，而不是{courses:[{“codeField”：“COMPSCI 101”…，所以我不确定在这种情况下如何从中获取JSONArray？你应该将我的答案标记为一种解决方案，以公正地对待帖子。
    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); // escape will mess up your json string
        }
        is.close();
        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <title>Service</title>
    <style>BODY { color: #000000; background-color: white; font-family: Verdana; margin-left: 0px; margin-top: 0px; } #content { margin-left: 30px; font-size: .70em; padding-bottom: 2em; } A:link { color: #336699; font-weight: bold; text-decoration: underline; } A:visited { color: #6699cc; font-weight: bold; text-decoration: underline; } A:active { color: #336699; font-weight: bold; text-decoration: underline; } .heading1 { background-color: #003366; border-bottom: #336699 6px solid; color: #ffffff; font-family: Tahoma; font-size: 26px; font-weight: normal;margin: 0em 0em 10px -20px; padding-bottom: 8px; padding-left: 30px;padding-top: 16px;} pre { font-size:small; background-color: #e5e5cc; padding: 5px; font-family: Courier New; margin-top: 0px; border: 1px #f0f0e0 solid; white-space: pre-wrap; white-space: -pre-wrap; word-wrap: break-word; } table { border-collapse: collapse; border-spacing: 0px; font-family: Verdana;} table th { border-right: 2px white solid; border-bottom: 2px white solid; font-weight: bold; background-color: #cecf9c;} table td { border-right: 2px white solid; border-bottom: 2px white solid; background-color: #e5e5cc;}</style>
  </head>
  <body>
    <div id="content">
      <p class="heading1">Service</p>
      <p xmlns="">Method not allowed. Please see the <a rel="help-page" href="http://redsox.tcs.auckland.ac.nz/734A/CSService.svc/help">service help page</a> for constructing valid requests to the service.</p>
    </div>
  </body>
</html>