HttpResponse中的異常在Android中執行

Question

我被HttpRequest方法的Exception困擾了幾個小時，我真的對此感到厭倦。 谷歌做了研究，但我找不到任何答案來解決它。 我需要執行一個http請求，以通過PHP腳本從數據庫獲取數據。 當我使用params調用表中所有行的方法時，一切進展順利：

url-“ http://android-connection.cba.pl/get_all_notes.php ”方法-“ GET”列表-空列表

但是當我嘗試獲取帶有參數的指定id行時，它會拋出一個異常：

url-“ http://android-connection.cba.pl/get_note.php ”方法-“ GET”列表-[noteid = 1]

我從類的doInBackground方法調用它，該方法擴展了AsyncTask。 如果您可以幫助我，這就是有問題的方法..謝謝！

public JSONObject makeHttpRequest(String url, String method, List<NameValuePair> params) {

    // Making HTTP request
    try {

        // check for request method
        if(method == "POST"){
            // request method is POST
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params));

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();

        }else if(method == "GET"){
            // request method is GET
            DefaultHttpClient httpClient = new DefaultHttpClient();
            String paramString = URLEncodedUtils.format(params, "utf-8");
            url += "?" + paramString;
            HttpGet httpGet = new HttpGet(url);
            Log.e("URL", url);
            HttpResponse httpResponse = httpClient.execute(httpGet);
            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.e("JSON", json);
    } 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;

}

並且有日志：

05-06 08:50:35.647: D/AndroidRuntime(3119): Shutting down VM
05-06 08:50:35.647: W/dalvikvm(3119): threadid=1: thread exiting with uncaught exception (group=0xb3ab9ba8)
05-06 08:50:35.697: E/AndroidRuntime(3119): FATAL EXCEPTION: main
05-06 08:50:35.697: E/AndroidRuntime(3119): Process: com.example.notatki, PID: 3119
05-06 08:50:35.697: E/AndroidRuntime(3119): android.os.NetworkOnMainThreadException
05-06 08:50:35.697: E/AndroidRuntime(3119):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1145)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at java.net.InetAddress.getAllByName(InetAddress.java:214)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at com.example.notatki.JSONParser.makeHttpRequest2(JSONParser.java:64)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at com.example.notatki.EditNoteActivity$GetNoteDetails$1.run(EditNoteActivity.java:145)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at android.os.Handler.handleCallback(Handler.java:733)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at android.os.Handler.dispatchMessage(Handler.java:95)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at android.os.Looper.loop(Looper.java:136)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at android.app.ActivityThread.main(ActivityThread.java:5017)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at java.lang.reflect.Method.invokeNative(Native Method)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at java.lang.reflect.Method.invoke(Method.java:515)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-06 08:50:35.697: E/AndroidRuntime(3119):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

聽起來您要么沒有編寫，要么沒有正確使用AsyncTask 。 這是我的版本，應該可以執行您的嘗試。 我跟進如何稱呼它。 有一些常見的錯誤，例如直接調用doInBackground方法而不是execute ，因此應該清除所有內容。

將此代碼包裝在AsyncTask ，請創建以下class ：

public class MyJSONRequest extends AsyncTask<Void, Void, Void> {

    String url;
    String method;
    List<NameValuePair> params;

    public MyJSONRequest(String url, String method, List<NameValuePair> params) {
        this.url = url;
        this.method = method;
        this.params = params;
    }

    @Override
    public Void doInBackground(Void...) {
        makeHttpRequest(url, method, params)
    }
}

現在，要完成任務且沒有錯誤，請執行以下操作：

List<NameValuePair> list = new ArrayList<NameValuePair>();
list.add(new BasicNameValuePair("noteid", "1"));
new MyJSONRequest("http://android-connection.cba.pl/get_note.php", "GET", list).execute();

---

另外，您應該注意if(method == "POST")和if(method == "POST")不會解決您的期望。 您需要將它們更改為if(method.equals("POST"))和if(method.equals("GET")) 。