UnknownHostException与HTTPConnection在安卓中的应用

Question

当我试图执行以下代码时，会出现UnknownHostException .

String line;
String url = "http://mywebsite.com";
URL theURL = new URL(url);
HttpURLConnection conn = (HttpURLConnection) theURL.openConnection();
BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
line = rd.readLine(); 
conn.disconnect();

我遵循了前几篇文章的建议，以确保权限标记在清单中正确显示为。我还确保我的Android有WIFI接入，并且我试图使用的网站是正确的。这似乎是StackOverflow：http://guerrarj.hubpages.com/hub/Tips-to-solve-the-UnknownHostException-on-Android上的一个流行资源。

堆栈跟踪是..。

java.net.UnknownHostException: the_website.com
    at java.net.InetAddress.lookupHostByName(InetAddress.java:512)
at java.net.InetAddress.getAllByNameImpl(InetAddress.java:300)
at java.net.InetAddress.getAllByName(InetAddress.java:259)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>(HttpConnection.java:69)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>(HttpConnection.java:48)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection$Address.connect(HttpConnection.java:322)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnectionPool.get(HttpConnectionPool.java:89)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getHttpConnection(HttpURLConnectionImpl.java:285)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.makeConnection(HttpURLConnectionImpl.java:267)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.retrieveResponse(HttpURLConnectionImpl.java:1018)
at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:512)
at com.example.privacyapp.MainActivity.scrapWeb(MainActivity.java:127)
at com.example.privacyapp.MainActivity.checkLocation(MainActivity.java:148)
at com.example.privacyapp.MainActivity$1.onLocationChanged(MainActivity.java:93)
at android.location.LocationManager$ListenerTransport._handleMessage(LocationManager.java:227)
at android.location.LocationManager$ListenerTransport.access$000(LocationManager.java:160)
at android.location.LocationManager$ListenerTransport$1.handleMessage(LocationManager.java:176)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:150)
at android.app.ActivityThread.main(ActivityThread.java:4263)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
at dalvik.system.NativeStart.main(Native Method)

更新：我的WIFI连接出现了故障。如果没有连接，UnknownHostException就会出现。

Answer 1

有时我们不得不写ip地址而不是“http://mywebsite.com”，所以尝试使用Ip地址。还请检查INTERNET权限标签是清单标签的子标签，而不是应用程序标签。检查一下这一次，希望这对你有帮助