当我尝试使用类HttpClient通过https://graph.facebook.com/oauth/access_token?client_id=xxx&client_secret=xxx8&grant_type=fb_exchange_token&fb_exchange_token=xxx拨打facebook时，我收到了Exception: Network is unreachable之类的回复。它以前工作，突然今天它停止工作。我没有更改任何代码和我的网络配置设置，我想知道可能是什么问题。当我检查日志时，错误是Caused by: java.net.SocketException: Network is unreachable。
如果我尝试直接从浏览器调用url https://graph.facebook.com/oauth/access_token?client_id=xxx&client_secret=xxx8&grant_type=fb_exchange_token&fb_exchange_token=xxx，我可以获得accessstoken。
我被困在这个问题上。谢谢。
异常堆栈跟踪如下。
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
at java.net.Socket.connect(Socket.java:507)
at java.net.Socket.connect(Socket.java:457)
at sun.net.NetworkClient.doConnect(NetworkClient.java:157)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:365)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:477)
at sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:280)
at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:337)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:176)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:736)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:162)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:133)
at eqs.snp.util.HTTPRequestClient.setContent(HTTPRequestClient.java:132)
at eqs.snp.sn.facebook.connector.FacebookAPI.refreshAccessToken(FacebookAPI.java:1750)
at eqs.snp.sn.facebook.facade.FacebookFacade.getRegisterUser(FacebookFacade.java:262)
at eqs.snp.sn.facebook.struts.action.FbUserAction.fbredirect(FbUserAction.java:195)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:440)
at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:279)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:163)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:249)
at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:93)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:128)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.ProfilingActivationInterceptor.intercept(ProfilingActivationInterceptor.java:104)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:148)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:128)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:468)
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
at org.apache.catalina.valves.FastCommonAccessLogValve.invoke(FastCommonAccessLogValve.java:482)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:174)
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:200)
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:283)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:773)
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:703)
at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:895)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Thread.java:595)
答案 0 :(得分：0)
您的环境中可能存在网络连接故障。我不确定您的电话是通过WiFi通过PC还是移动应用程序进行的。您没有选择，只能等到重新建立连接。
BTW：来自浏览器和您的应用的呼叫是否同时进行？
或者，您可以使用ping graph.facebook.com等检查网络连接的可用性。
您还可以在here查看类似查询的说明。
答案 1 :(得分：0)
问题是服务器上运行jdk。也许有些文件已损坏。所以安装一个新的jdk并运行应用程序，就可以了。
答案 2 :(得分：0)
如果你正在运行Debian，它可能与IPv6设置有关。每http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=560044
包：sun-java6-jdk 版本：6-17-1 严重性：重要
Netbase最近推出了sysctl-setting /etc/sysctl.d/bindv6only.conf中的net.ipv6.bindv6only = 1 设置可能是挤压中的默认设置。
此设置会破坏java中的网络，并且任何流量都将始终存在 导致“java.net.SocketException：网络无法访问”。
它可能应该是一个rc-bug，但现在设置很重要， 因为用户可以轻松纠正这个问题。
快速修复受此影响的用户：
sudo sed -i's / net.ipv6.bindv6only \ = \ 1 / net.ipv6.bindv6only \ = \ 0 /'\ /etc/sysctl.d/bindv6only.conf&&&&&& sudo invoke-rc.d procps restart