一个发邮件的例子

import javax.mail.*;
import javax.mail.internet.*;
import java.util.Properties;
import java.util.Date;
public class sendMail
{
public static void main(String args[]) throws Exception
{
// String host = "smtp.sina.com.cn";
String host = "smtp.163.com";
String from = "test@163.com";
//发送的邮件
String to = "gohands@163.com";
String to2 = gohands@163.com;
String username = "test";
String password = "passwd";
String fileAttachment = "G:Documents and SettingsaaaMy DocumentsMy eBooks附件.txt";
// Get system properties
Properties props = new Properties();
// Setup mail server
props.put("mail.smtp.host", host);
props.put("mail.smtp.auth", "true");
// Get session
Session session = Session.getDefaultInstance(props);
// watch the mail commands go by to the mail server
session.setDebug(true);
// Define message
MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));
message.addRecipient(Message.RecipientType.TO,
new InternetAddress(to));
message.addRecipient(Message.RecipientType.TO,
new InternetAddress(to2));
message.setSubject("标题");
message.setText("正文");
// message.setContentLanguage();
// FileTypeMap
FileDataSource fds=new FileDataSource(fileAttachment);
//
//
message.setDataHandler(new DataHandler(fds));
// message.setDataHandler(
// new DataHandler(source));
// Send message
message.setSentDate(new Date());
message.saveChanges();
Transport transport = session.getTransport("smtp");
transport.connect(host, username, password);
transport.sendMessage(message, message.getAllRecipients());
System.out.println("over");
transport.close();
}
}

补充：Jsp教程,邮件