apache james向外网发送邮件时提示错误

我的代码如下：package jamesDemo;import org.apache.commons.mail.EmailException;
import org.apache.commons.mail.HtmlEmail;
public class FristDemo {
public static void sendMail(String contents, String toEmail) throws EmailException {  
        try {  
            HtmlEmail email = new HtmlEmail();  
              
            // 设定smtp服务器  
            email.setHostName("192.168.0.45");   
              
            // 设定收件人  
            email.addTo(toEmail);  
              
            //发送的邮件地址  
            email.setFrom("[email protected]", "bjtest");  
              
            // 设定smtp服务器的认证资料信息  
            email.setAuthentication("bjtest", "123456");   
              
            email.setSubject("标题");  
              
            // 设定是否使用SSL  
            //email.setSSL(Boolean.TRUE);  
              
            // 设定SSL端口gmail端口465、其它25  
            //email.setSslSmtpPort("465");   
              
            //设定Debug输出信息  
            //email.setDebug(true);   
              
            //设定内容的语言集  
            email.setCharset("UTF-8");  
              
            email.setHtmlMsg(contents);  
              
            email.send();  
              
            System.out.println("邮件发送成功");  
        } catch (Exception e) {  
            System.out.println("邮件发送失败");  
            e.printStackTrace();  
        }  
    }  
      
    public static void main(String[] args) throws EmailException {  
        String str = "<html>您好,chen!</html>";  
        String email="[email protected]";  
        sendMail(str,email);;  
    }  }
运行时提示错误：
Exception in thread "main" java.lang.NoClassDefFoundError: javax/mail/Message
at test.jamesDemo.sendMail(jamesDemo.java:9)
at test.jamesDemo.main(jamesDemo.java:51)
Caused by: java.lang.ClassNotFoundException: javax.mail.Message
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)
... 2 more网上查了很久资料都没有找到答案，那个急啊，恳求各位大神给出答案！！！不胜感激apache邮件语言java