访问 URL 时出现 java.net.UnknownHostException
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java.net.UnknownHostException when accessing a URL
提问by blue-sky
Below code :
下面的代码：
URL oracle = new URL("http://www.oracle.com/");
URLConnection inputStream =oracle.openConnection();
InputStream in = inputStream.getInputStream();
Throws this exception :
抛出这个异常：
java.net.UnknownHostException: www.oracle.com
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:195)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:529)
at java.net.Socket.connect(Socket.java:478)
at sun.net.NetworkClient.doConnect(NetworkClient.java:163)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:395)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:530)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:234)
at sun.net.www.http.HttpClient.New(HttpClient.java:307)
at sun.net.www.http.HttpClient.New(HttpClient.java:324)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:970)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:911)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:836)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1172)
I think this exception is thrown because the proxy server is blocking my connection? I just want to parse some data from the URL, can I accomplish this without running into the firewall ?
我认为抛出这个异常是因为代理服务器阻止了我的连接？我只想从 URL 中解析一些数据，我可以在不进入防火墙的情况下完成此操作吗？
采纳答案by Philip Helger
If you are using a proxy server, please make sure that you are setting the appropriate system properties. See the Oracle page at http://docs.oracle.com/javase/6/docs/technotes/guides/net/proxies.htmlfor details.
如果您使用代理服务器，请确保您设置了适当的系统属性。有关详细信息，请参阅位于http://docs.oracle.com/javase/6/docs/technotes/guides/net/proxies.html的 Oracle 页面。
回答by tony9099
Make sure to include the below line in your manifest. It should be a direct child of manifest node.
确保在清单中包含以下行。它应该是清单节点的直接子节点。
<uses-permission android:name="android.permission.INTERNET" />
