一步步调通Openfire3.10.2+Smack4.1.4官方Demo

首先在电脑上安装Openfire服务器（本文安装的版本为Openfire 3.10.2）

Openfire下载地址http://www.igniterealtime.org/downloads/index.jsp 

本文Openfire服务器名称为192.169.20.246

Smack 4.1.4的官方文档下载地址包括jar包和javadoc（官方给的解释Easy to use Java XMPP client library.） 
http://www.igniterealtime.org/downloads/download-landing.jsp?file=smack/smack_4_1_4.zip

下载Smack之后从文档smack_4_1_4/releasedocs/documentation/index.html给的示例

// Create a connection to the gwcheng-pc server on a specific port.
XMPPTCPConnectionConfiguration config = XMPPTCPConnectionConfiguration.builder()
.setUsernameAndPassword("<span style="color: rgb(0, 136, 0); font-family: 'Source Code Pro', monospace; font-size: 14px; line-height: 20.3px; white-space: pre;">wangzheng</span>", "<span style="color: rgb(0, 136, 0); font-family: 'Source Code Pro', monospace; font-size: 14px; line-height: 20.3px; white-space: pre;">wz20120404</span>")
.setServiceName("<span style="color: rgb(136, 0, 0); font-family: 'Source Code Pro', monospace; font-size: 14px; line-height: 20.3px; white-space: pre;">192.169.20.246</span>")
.setHost("<span style="color: rgb(136, 0, 0); font-family: 'Source Code Pro', monospace; font-size: 14px; line-height: 20.3px; white-space: pre;">192.169.20.246</span>")
.build();
AbstractXMPPConnection conn2 = new XMPPTCPConnection(config);
conn2.connect();建立一个java工程，拷贝smack_4_1_4\libs\下的jar包到自己的工程里。 

运行上面的代码（代码中”wangzheng”和"wz20120404"是我在openfire中注册的用户名和密码”192.169.20.246”为我的openfire服务器名称
） 

运行上面的程序，会报如下的错误

Exception in thread "main" java.lang.NoClassDefFoundError: org/xmlpull/v1/XmlPullParserFactory
Caused by: java.lang.ClassNotFoundException: org.xmlpull.v1.XmlPullParserFactory

这个错误很明显是缺少jar包 xmlpull.jar，此处导入xmlpull-1.1.3.1.jar 

导入之后运行还是会报错

Exception in thread "main" java.lang.ExceptionInInitializerError
Caused by: java.lang.IllegalStateException: org.xmlpull.v1.XmlPullParserException: caused by: org.xmlpull.v1.XmlPullParserException: resource not found: /META-INF/services/org.xmlpull.v1.XmlPullParserFactory make sure that parser implementing XmlPull API is available
Caused by: org.xmlpull.v1.XmlPullParserException: caused by: org.xmlpull.v1.XmlPullParserException: resource not found: /META-INF/services/org.xmlpull.v1.XmlPullParserFactory make sure that parser implementing XmlPull API is available

这种错误还是缺少jar包 kxml.jar，此处导入kxml2-2.3.0.jar 

导入之后运行还是会报错

Exception in thread "main" java.lang.NoClassDefFoundError: de/measite/minidns/DNSCache
Caused by: java.lang.ClassNotFoundException: de.measite.minidns.DNSCache

继续导入jar包 minidns.jar，此处导入minidns-0.1.7.jar 

导入之后运行还是会报错

Exception in thread "main" java.lang.NoClassDefFoundError: org/jxmpp/util/cache/ExpirationCache
Caused by: java.lang.ClassNotFoundException: org.jxmpp.util.cache.ExpirationCache

继续导入jar包 jxmpp-core-0.5.0-alpha6.jar和 jxmpp-util-cache-0.4.0-alpha1.jar 

导入之后运行还是会报错

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/http/conn/ssl/StrictHostnameVerifier
Caused by: java.lang.ClassNotFoundException: org.apache.http.conn.ssl.StrictHostnameVerifier

继续导入jar包 httpclient-4.4.1.jar 

导入之后运行还是会报错

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
Caused by: java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory

继续导入jar包 commons-logging-1.2.jar 

导入之后运行还是会报错

org.jivesoftware.smack.SmackException: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
Caused by: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

这个错误造成的原因是：Openfire 服务器（安全设置问题），这个安全证书问题，我会单独抽出来，进行详细的说明。

openfire服务器端解决办法：
“服务器设置”－－“安全设置”－－－将“客户端安全联接”中由“非必须”，修改为“自定义”，另外把“旧的SSL方式”和“TLS方式”都设置为无效。



至此，我们完成了XMPP服务开发第一步：XMPP服务器连接

package com.openfire.util;

import java.io.IOException;

import org.jivesoftware.smack.AbstractXMPPConnection;
import org.jivesoftware.smack.SmackException;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.tcp.XMPPTCPConnection;
import org.jivesoftware.smack.tcp.XMPPTCPConnectionConfiguration;

public class ConnectionUtil {
//简单连接
public boolean connect(String username,String password,String serverName){
boolean target=false;
XMPPTCPConnectionConfiguration config = XMPPTCPConnectionConfiguration.builder()
.setUsernameAndPassword(username, password)
.setServiceName(serverName)
.setHost(serverName)
.setPort(5222)
.build();
AbstractXMPPConnection conn = new XMPPTCPConnection(config);
try {
conn.connect();
target = conn.isConnected();
if(target){
System.out.println("XMPP 服务器连接成功");
}else{
System.out.println("XMPP 服务器连接不成功");
}
} catch (SmackException | IOException | XMPPException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return target;

}

}

package com.openfire.main;

import com.openfire.util.ConnectionUtil;

public class ConnectionTest {

public static void main(String[] args) {
// TODO Auto-generated method stub
ConnectionUtil connection=new ConnectionUtil();
connection.connect("wangzheng", "wz20120404", "192.169.20.246");
}

}