使用XMPP协议连接服务器时，总是报错，错误代码如下：

Question

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: org/xmlpull/v1/XmlPullParser
at org.jivesoftware.smack.Connection.<clinit>(Connection.java:118)
at org.jivesoftware.smack.ConnectionConfiguration.<init>(ConnectionConfiguration.java:73)
at Login_UI$1.actionPerformed(Login_UI.java:57)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$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$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$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.lang.ClassNotFoundException: org.xmlpull.v1.XmlPullParser
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 39 more

Answer 1

上面是错误提示，这是代码：
System.out.println("前");

ConnectionConfiguration conf = new ConnectionConfiguration(server, 5222);//org.jivesoftware.smack.ConnectionConfiguration

System.out.println("后");
XMPPConnection conn = null;
try {
conn=new XMPPConnection(conf);  
conn.connect();
System.out.println("连接服务器成功！！！");
} catch(XMPPException e1) {   System.out.println("连接服务器失败！！！");
//e.printStackTrace();
}

Answer 2

经过查看，代码只能运行到 ConnectionConfiguration conf = new ConnectionConfiguration(server, 5222);  这句，下面的就不能运行了。

Answer 3

org.xmlpull.v1.XmlPullParser
这个类没有找到，查看是否正确导入了

Answer 4

我来结贴吧  我的做法是在src目录下建立lib目录  放入asmack,jar 然后设置lib文件“Use as a Source Folder”，然后add jar 选择本项目下的lib目录下的asmack.jar ，就可以了。

Answer 5

smack,jar 
smackx.jar这两个都加上就可以了，