发邮件首先引入j2ee的包路径到ClassPath,已经安装Jbuilder的可以在它的安装路径lib目录下找
到mail.jar,activation.jar,将这两个包加入系统的环境变量,那么即使不用JBuilder开发的话也可以
使用了.

程序:

import java.io.*;
import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;

/**
* <p>Title: 简易MailBean</p>
* <p>Description: 提供简便的Mail发送功能（/p>
* <p>Copyright: Copyright (c) 2003</p>
* version 1.0
*/

class ExtendString {
public ExtendString() {
}
/**
去掉字符串两端的空白字符,并将字符串转化为中国的标准字符gb2312的字符串.
*/
public String CS(String str) { //去掉字符串2端的空白字符
try {
if (str == null)
return "";
str = str.trim();
if (str == null)
return "";
str = new String(str.getBytes("8859_1"), "GBK");
}
catch (Exception e) {
System.out.println(e);
}
return str;
}

}

public class SendMail
{
private String errMsg = "";
private ExtendString ExStr = new ExtendString();

private String sender = "";//发件人地址
private String smtpHost = "";//邮件发送服务器（smtp）
private String user = ""; //登录用户名
private String password = "";//登录密码

private String subject = "";//mail主题

public SendMail()
{
this.setPropertiesAttri();
}

private void setPropertiesAttri()
{
try
{
InputStream is = getClass().getResourceAsStream("MailServer.properties");
Properties prop = new Properties();
prop.load(is);

this.setSmtpHost(prop.get("SmtpHost").toString());
this.setUser(prop.get("User").toString());
this.setPassword(prop.get("Password").toString());
this.setSender(prop.get("Sender").toString());
this.setSubject(ExStr.CS(prop.get("Subject").toString()));
}
catch(Exception ex)
{
System.err.println("ex1 in sendmail.java:"+ex.toString());
}
}
/** 设置发件人地址 */

public void setSender(String sender)
{
this.sender = sender;
}

public String getSender()
{
return sender;
}

/** 设置邮件发送服务器（smtp） */
public void setSmtpHost(String smtpHost) {this.smtpHost = smtpHost;}
public String getSmtpHost() {return smtpHost;}

/** 设置登录用户名 */
public void setUser(String user)
{
this.user = user;
}
public String getUser()
{
return user;
}

/** 设置登录密码 */
public void setPassword(String password)
{
this.password = password;
}
public String getPassword()
{
return password;
}

/** 设置mail主题 */
public void setSubject(String subject)
{
this.subject = subject;
}
public String getSubject()
{
return subject;
}

/**
* 使用smtp发送邮件 主程序
* throws MessagingException mail发送失败
*/
public void smtp(String receiver,String content) throws MessagingException
{
if (smtpHost == null) throw new MessagingException("smtpHost not found");
if (user == null) throw new MessagingException("user not found");
if (password == null) throw new MessagingException("password not found");

Properties properties = new Properties();
properties.put("mail.smtp.host", smtpHost);//设置smtp主机
properties.put("mail.smtp.auth", "true");//使用smtp身份验证

Session session = Session.getDefaultInstance(properties,
new Authenticator(){
public PasswordAuthentication getPasswordAuthentication(){
return new PasswordAuthentication(user, password);
}
});

//获得邮件会话对象
MimeMessage mimeMsg = new MimeMessage(session);//创建MIME邮件对象
if (sender != null)//设置发件人地址
{
mimeMsg.setFrom(new InternetAddress(sender));
}
if (receiver != null)//设置收件人地址
{
mimeMsg.setRecipients(Message.RecipientType.TO, parse(receiver));
}
if (subject != null)//设置邮件主题
{
mimeMsg.setSubject(subject, "GBK");
}
MimeBodyPart part = new MimeBodyPart();//mail内容部分
part.setText(content == null ? "" : content, "GBK");

//设置邮件格式为html cqc
part.setContent(content.toString(),"text/html;charset=GBK");
Multipart multipart = new MimeMultipart();
multipart.addBodyPart(part);//在 Multipart 中增加mail内容部分
mimeMsg.setContent(multipart);//增加 Multipart 到信息体
mimeMsg.setSentDate(new Date());//设置发送日期
Transport.send(mimeMsg);//发送邮件
}

/** 解析地址集合字符串 */
private InternetAddress[] parse(String addressSet) throws AddressException
{
ArrayList list = new ArrayList();
StringTokenizer tokens = new StringTokenizer(addressSet, ";");
while (tokens.hasMoreTokens())
{
list.add(new InternetAddress(tokens.nextToken().trim()));
}
InternetAddress[] addressArray = new InternetAddress[list.size()];
list.toArray(addressArray);
return addressArray;
}

/**
* 供外部调用的接口
*/

public boolean sendMails(String mail,String content)
{
int mailLen = 0 ;
int contentLen= 0;
if (mail == null||content==null)
{
return false;
}

try
{
this.smtp(mail,content);
}
catch(Exception ex)
{
System.err.println("ex2 in sendmail.java:"+ex.toString());
}

return true;
}

public static void main (String[] args)
{
SendMail mail = new SendMail();
String email = "feng_leiecfounder.com;ladofwind163.com";
String content = "账号:123 密码:123 <br/>感谢您注册!<br/><a href='http://www.xxxx.com.cn' target='_blank'>www.xxxx.com.cn</a><br/>此致<br/>xxxx <br/>即日";
try
{
mail.sendMails(email,content);
}
catch (Exception ex)
{
System.err.println("ex33:"+ex.toString());
}
}


}

编译通过后,在class文件的目录下建立一个文本文件MailServer.properties,
格式:
SmtpHost=smtp.163.com
User=user
Password=pwd
Sender=csdncsdn.com
Subject=Hello


运行程序即可实现邮件发送!