本例基于javamail的jar包,下载地址: http://www.oracle.com/technetwork/java/index-138643.html

import java.util.Date;
import java.util.Enumeration;
import java.util.Properties;
import java.util.Vector;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;

/**
 * Title: 使用javamail发送邮件 Description: 演示如何使用javamail包发送电子邮件。这个实例可群发,可发送多附件
 * Filename: SendMailUtil.java
 */
public class SendMailUtil {
	String to = ""; // 收件人
	String from = ""; // 发件人
	String host = ""; // smtp主机
	String username = ""; // 用户名
	String password = ""; // 密码
	String filename = ""; // 附件文件名
	String subject = ""; // 邮件主题
	String content = ""; // 邮件正文
	Vector<Object> file = new Vector<Object>(); // 附件文件集合

	/**
	 * <br>
	 * 方法说明:默认构造器 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public SendMailUtil() {
	}

	/**
	 * <br>
	 * 方法说明:构造器,提供直接的参数传入 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public SendMailUtil(String to, String from, String smtpServer,
			String username, String password, String subject, String content) {
		this.to = to;
		this.from = from;
		this.host = smtpServer;
		this.username = username;
		this.password = password;
		this.subject = subject;
		this.content = content;
	}

	/**
	 * <br>
	 * 方法说明:把主题转换为中文 <br>
	 * 输入参数:String strText <br>
	 * 返回类型:
	 */
	public String transferChinese(String strText) {
		try {
			strText = MimeUtility.encodeText(new String(strText.getBytes()),
					"utf-8", "B");
		} catch (Exception e) {
			e.printStackTrace();
		}
		return strText;
	}

	/**
	 * <br>
	 * 方法说明:往附件组合中添加附件 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public void addAttachFile(String fname) {
		file.addElement(fname);
	}

	/**
	 * <br>
	 * 方法说明:多人发送,分解邮件发送地址 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public InternetAddress[] ManyAddress(String to) {
		// 将要发送的邮件地址根据";"号放在一个数组中
		String[] toAddress = to.split(",");
		// 要发送的邮件地址数量
		int toCount = toAddress.length;
		// 格式化要发送的邮件地址
		InternetAddress[] address = new InternetAddress[toCount];
		try {
			for (int i = 0; i < toCount; i++) {
				address[i] = new InternetAddress(toAddress[i]);
			}
		} catch (AddressException e) {
			e.printStackTrace();
		}
		return address;
	}

	/**
	 * <br>
	 * 方法说明:发送邮件 <br>
	 * 输入参数: <br>
	 * 返回类型:boolean 成功为true,反之为false
	 */
	public boolean sendMail() {
		// 构造mail session,两个参数分别是内容和图片
		Properties props = System.getProperties();
		props.put("mail.smtp.host", host);
		props.put("mail.smtp.auth", "true");
		Session session = Session.getDefaultInstance(props,
				new Authenticator() {
					public PasswordAuthentication getPasswordAuthentication() {
						// 用户登录stmp服务器时候验证用户名和密码。
						return new PasswordAuthentication(username, password);
					}
				});
		try {
			// 构造MimeMessage 并设定基本的值
			MimeMessage msg = new MimeMessage(session);
			msg.setFrom(new InternetAddress(from));
			// 单人发送
			// InternetAddress[] address = { new InternetAddress(to) };

			// 多人发送
			InternetAddress[] address = ManyAddress(to);
			msg.setRecipients(Message.RecipientType.TO, address);
			subject = transferChinese(subject);
			msg.setSubject(subject);
			// 构造Multipart
			Multipart mp = new MimeMultipart();
			// 向Multipart添加正文
			MimeBodyPart mbpContent = new MimeBodyPart();
			mbpContent.setText(content);
			// 向MimeMessage添加(Multipart代表正文)
			mp.addBodyPart(mbpContent);
			// 向Multipart添加附件
			Enumeration<Object> efile = file.elements();
			while (efile.hasMoreElements()) {
				MimeBodyPart mbpFile = new MimeBodyPart();
				filename = efile.nextElement().toString();
				FileDataSource fds = new FileDataSource(filename);
				mbpFile.setDataHandler(new DataHandler(fds));
				mbpFile.setFileName(transferChinese(fds.getName()));
				System.out.println(mbpFile.getFileName());
				// 向MimeMessage添加(Multipart代表附件)
				mp.addBodyPart(mbpFile);
			}
			file.removeAllElements();
			// 向Multipart添加MimeMessage
			msg.setContent(mp);
			msg.setSentDate(new Date());
			// 发送邮件
			Transport.send(msg);
		} catch (MessagingException mex) {
			System.out.println("邮件发送异常,请检查邮件配置信息是否正确!");
			mex.printStackTrace();
			return false;
		}
		System.out.println("邮件发送成功!");
		return true;
	}

	/**
	 * <br>
	 * 方法说明:主方法,用于测试 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public static void main(String[] args) {
		SendMailUtil sendmail = new SendMailUtil();
		sendmail.setHost("smtp.qq.com"); // 邮件协议
		sendmail.setUsername("test"); // 发件人
		sendmail.setPassword("zpj2991575"); // 发件人密码
		sendmail.setFrom(""); // 发件人地址
		sendmail.setTo(""); // 收件人地址,多人地址用","分开
		sendmail.setSubject("你好,这是测试邮件!"); // 邮件主题
		sendmail.setContent("你好这是一个带多附件的测试邮件!"); // 发送附件
		sendmail.addAttachFile("C:\\Users\\Administrator\\Desktop\\JSF新手入门最好的教程.doc"); // 发送附件01
		sendmail.addAttachFile("C:\\Users\\Administrator\\Desktop\\简单JSF实例参考.doc"); // 发送附件02
		sendmail.sendMail();
	}

	/**
	 * <br>
	 * 方法说明:设置邮件服务器地址 <br>
	 * 输入参数:String host 邮件服务器地址名称 <br>
	 * 返回类型:
	 */
	public void setHost(String host) {
		this.host = host;
	}

	/**
	 * <br>
	 * 方法说明:设置登录服务器校验密码 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public void setPassword(String password) {
		this.password = password;
	}

	/**
	 * <br>
	 * 方法说明:设置登录服务器校验用户 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public void setUsername(String username) {
		this.username = username;
	}

	/**
	 * <br>
	 * 方法说明:设置邮件发送目的邮箱 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public void setTo(String to) {
		this.to = to;
	}

	/**
	 * <br>
	 * 方法说明:设置邮件发送源邮箱 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public void setFrom(String from) {
		this.from = from;
	}

	/**
	 * <br>
	 * 方法说明:设置邮件主题 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public void setSubject(String subject) {
		this.subject = subject;
	}

	/**
	 * <br>
	 * 方法说明:设置邮件内容 <br>
	 * 输入参数: <br>
	 * 返回类型:
	 */
	public void setContent(String content) {
		this.content = content;
	}
}



如果使用myeclipse,发生异常请删除MyEclipse中javaee.jar包中的 mail和 activation,然后导入mail.jar和actvation.jar包即可.