Question

我正在尝试使用google提供的facebook API在java中构建桌面应用程序。我有很多问题：

1）我是否必须使用套接字编程？（因为我是新手，我没有：/）

2）当我尝试创建一个auth_token时，它在facebook api中给出一个java.net.UnknownHost异常。

任何额外的信息都会有很大的帮助。：）

java.lang.RuntimeException: java.net.UnknownHostException: api.facebook.com
at com.google.code.facebookapi.BasicClientHelper.runtimeException(BasicClientHelper.java:123)
at com.google.code.facebookapi.ExtensibleClient.callMethod(ExtensibleClient.java:538)
at com.google.code.facebookapi.ExtensibleClient.callMethod(ExtensibleClient.java:446)
at com.google.code.facebookapi.ExtensibleClient.auth_createToken(ExtensibleClient.java:860)
at com.google.code.facebookapi.SpecificReturnTypeAdapter.auth_createToken(SpecificReturnTypeAdapter.java:73)
at facebookConnection.FbStartingPoint.<init>(FbStartingPoint.java:26)
at sourcepoint.FirstWindow$1.actionPerformed(FirstWindow.java:41)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$000(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$2.run(Unknown Source)
at java.awt.EventQueue$2.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
    Caused by: java.net.UnknownHostException: api.facebook.com
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.net.NetworkClient.doConnect(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient.<init>(Unknown Source)
at sun.net.www.http.HttpClient.New(Unknown Source)
at sun.net.www.http.HttpClient.New(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.connect(Unknown Source)
at com.google.code.facebookapi.ExtensibleClient.postRequest(ExtensibleClient.java:583)
at com.google.code.facebookapi.ExtensibleClient.callMethod(ExtensibleClient.java:534)
... 41 more

Answer 1

听起来您的计算机无法访问api.facebook.com主机。您使用代理连接到Internet吗？

尝试使用telnet确保整台计算机可以连接到互联网（不仅仅是代理配置的驱动程序）：

> telnet api.facebook.com 80
Trying 66.220.149.99...
Connected to api.facebook.com.
Escape character is '^]'.
GET /

HTTP/1.1 400 Bad Request
Content-Type: text/html
Date: Sat, 25 Aug 2012 16:29:53 GMT
Connection: close
Content-Length: 134

<HTML><HEAD>
<TITLE>400 Bad Request</TITLE>
</HEAD><BODY>
<H1>Method Not Implemented</H1>
Invalid method in request<P>
</BODY></HTML>
Connection closed by foreign host.

Answer 2

api.facebook.com是旧的REST API的端点，不推荐使用;您可能应该连接到graph.facebook.com

尽管如此，api.facebook.com应该是可解析的，并且如果您正在使用旧版API仍然可以使用。

这几乎肯定是您的网络，防火墙，计算机，DNS或JDK的问题 - 您的代码连接到Facebook的问题，而不是Facebook方面的问题

使用Facebook API的Java桌面应用程序（java.net.UnknownHost异常）

2 个答案: