java.net.UnknownHostException:appengine.google.com

Question

得到了这个错误.知道怎么摆脱它吗？

昨天它工作正常,但今天我收到了这些错误.我看到了一个已知的问题 - 链接.但我还没有找到任何解决方案..

 Oct 16, 2012 4:01:59 PM com.google.appengine.tools.info.RemoteVersionFactory getVersion

INFO: Unable to access https://appengine.google.com/api/updatecheck?runtime=java&release=1.7.1&timestamp=1345058163&api_versions=['1.0']
java.net.UnknownHostException: appengine.google.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 com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:559)
    at com.sun.net.ssl.internal.ssl.BaseSSLSocketImpl.connect(BaseSSLSocketImpl.java:141)
    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.protocol.https.HttpsClient.<init>(HttpsClient.java:272)
    at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:329)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:172)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:911)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:158)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1172)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:234)
    at java.net.URL.openStream(URL.java:1010)
    at com.google.appengine.tools.info.RemoteVersionFactory.getVersion(RemoteVersionFactory.java:76)
    at com.google.appengine.tools.info.UpdateCheck.checkForUpdates(UpdateCheck.java:99)
    at com.google.appengine.tools.info.UpdateCheck.doNagScreen(UpdateCheck.java:174)
    at com.google.appengine.tools.info.UpdateCheck.maybePrintNagScreen(UpdateCheck.java:142)
    at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:289)
    at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:48)
    at com.google.appengine.tools.development.DevAppServerMain.<init>(DevAppServerMain.java:249)
    at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:225)
Oct 16, 2012 4:01:59 PM com.google.apphosting.utils.jetty.JettyLogger info
INFO: Logging to JettyLogger(null) via com.google.apphosting.utils.jetty.JettyLogger
Oct 16, 2012 4:02:00 PM com.google.apphosting.utils.config.AppEngineWebXmlReader readAppEngineWebXml
INFO: Successfully processed D:\WorkSpace\GAE\GST\war\WEB-INF/appengine-web.xml
Oct 16, 2012 4:02:00 PM com.google.apphosting.utils.config.AbstractConfigXmlReader readConfigXml
INFO: Successfully processed D:\WorkSpace\GAE\GST\war\WEB-INF/web.xml
Oct 16, 2012 4:02:02 PM com.google.appengine.tools.development.DevAppServerImpl start

Answer 1

如果您在应用引擎应用程序中使用Java 8,则需要包括

<url-stream-handler> urlfetch </ url-stream-handler> 

在appengine-web.xml.

appengine-web.xml参考

Answer 2

我假设当您尝试将 Eclipse 项目作为 Web 应用程序运行时，您会在 Eclipse IDE 中看到这一点。

GAE 插件只是检查是否有更新的 AppEngine SDK 可供下载。如果有比您当前使用的版本更新的版本，那么它会让您知道这一点。该错误是因为在该情况下，可能存在网络错误并且无法连接。就运行您的应用程序而言，它是无害的。

但是，如果您的应用程序依赖于访问某些外部网络服务，那么如果您的开发环境中仍然存在网络问题，它们也可能会失败。