<分区>
String response = getResultForRequest(url);
其中“url”是 JSON 格式，使用 http GET 方法返回一堆数据。
public static String getResultForRequest(String urlString)
throws IOException {
URL url = new URL(urlString);
HttpURLConnection urlConnection = (HttpURLConnection) url
.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoInput(true);
urlConnection.setDoOutput(true);
urlConnection.connect();
InputStream is = urlConnection.getInputStream();
if (is == null)
return null;
StringBuffer sb = new StringBuffer();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line = null;
try {
while ((line = br.readLine()) != null)
sb.append(line);
} finally {
br.close();
is.close();
}
return sb.toString();
}
我无法从我在 getResultForRequest(url) 方法中传递的“url”获取 JSON 格式的数据。我在 urlConnection.connect(); 中遇到错误。 AndroidManifest.xml 文件中还提供了 Internet 权限。
这是我的日志。
10-09 13:27:35.264: E/AndroidRuntime(9984): FATAL EXCEPTION: main
10-09 13:27:35.264: E/AndroidRuntime(9984): java.lang.RuntimeException: Unable to start activity ComponentInfo{}: android.os.NetworkOnMainThreadException
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.ActivityThread.access$600(ActivityThread.java:140)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.os.Handler.dispatchMessage(Handler.java:99)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.os.Looper.loop(Looper.java:137)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.ActivityThread.main(ActivityThread.java:4898)
10-09 13:27:35.264: E/AndroidRuntime(9984): at java.lang.reflect.Method.invokeNative(Native Method)
10-09 13:27:35.264: E/AndroidRuntime(9984): at java.lang.reflect.Method.invoke(Method.java:511)
10-09 13:27:35.264: E/AndroidRuntime(9984): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1008)
10-09 13:27:35.264: E/AndroidRuntime(9984): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:775)
10-09 13:27:35.264: E/AndroidRuntime(9984): at dalvik.system.NativeStart.main(Native Method)
10-09 13:27:35.264: E/AndroidRuntime(9984): Caused by: android.os.NetworkOnMainThreadException
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1118)
10-09 13:27:35.264: E/AndroidRuntime(9984): at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
10-09 13:27:35.264: E/AndroidRuntime(9984): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
10-09 13:27:35.264: E/AndroidRuntime(9984): at java.net.InetAddress.getAllByName(InetAddress.java:214)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:70)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:340)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:315)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpsURLConnectionImpl$HttpsEngine.makeSslConnection(HttpsURLConnectionImpl.java:461)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpsURLConnectionImpl$HttpsEngine.connect(HttpsURLConnectionImpl.java:433)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:289)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:239)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
10-09 13:27:35.264: E/AndroidRuntime(9984): at libcore.net.http.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:165)
10-09 13:27:35.264: E/AndroidRuntime(9984): at com.csoft.foursquare.FoursquareService.getResultForRequest(Service.java:564)
10-09 13:27:35.264: E/AndroidRuntime(9984): at com.csoft.foursquare.FoursquareService.getUserDetails(Service.java:376)
10-09 13:27:35.264: E/AndroidRuntime(9984): at com.csoft.checkin.CheckinHistoryActivity.onCreate(HistoryActivity.java:52)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.Activity.performCreate(Activity.java:5206)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
10-09 13:27:35.264: E/AndroidRuntime(9984): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064)
10-09 13:27:35.264: E/AndroidRuntime(9984): ... 11 more
提前致谢。