关键技术：

	1、MimeMessage的setRecipients方法设置邮件的收件人，其中Message.RecipientType.TO常量表示收件人类型是邮件接收者，Message.RecipientType.
CC常量表示收件人类型是抄送者，Message.RecipientType.BCC常量表示收件人的类型是密送着。

	2、在调用MimeMessage的setRecipients方法时，除了可以指定收件人的类型外，还可以传入一个数组，指定多个收件人的地址。

SourceCode:

import javax.mail.Address;

import javax.mail.BodyPart;

import javax.mail.Message;

import javax.mail.MessagingException;

import javax.mail.Multipart;

import javax.mail.Session;

import javax.mail.Transport;

import javax.mail.internet.InternetAddress;

import javax.mail.internet.MimeBodyPart;

import javax.mail.internet.MimeMessage;

import javax.mail.internet.MimeMultipart;

public class MultiMailsender {

    /**

     * 发送邮件给多个接收者

     * @param mailInfo    带发送邮件的信息

     * @return

     */

    public static boolean sendMailtoMultiReceiver(MultiMailSenderInfo mailInfo){

        MyAuthenticator authenticator = null;

        if (mailInfo.isValidate()) {

            authenticator = new MyAuthenticator(mailInfo.getUserName(),

                    mailInfo.getPassword());

        }

        Session sendMailSession = Session.getInstance(mailInfo

                .getProperties(), authenticator);

        try {

            Message mailMessage = new MimeMessage(sendMailSession);

            // 创建邮件发送者地址

            Address from = new InternetAddress(mailInfo.getFromAddress());

            mailMessage.setFrom(from);

            // 创建邮件的接收者地址，并设置到邮件消息中

            Address[] tos = null;

            String[] receivers = mailInfo.getReceivers();

            if (receivers != null){

                // 为每个邮件接收者创建一个地址

                tos = new InternetAddress[receivers.length + 1];

                tos[0] = new InternetAddress(mailInfo.getToAddress());

                for (int i=0; i<receivers.length; i++){

                    tos[i+1] = new InternetAddress(receivers[i]);

                }

            } else {

                tos = new InternetAddress[1];

                tos[0] = new InternetAddress(mailInfo.getToAddress());

            }

            // 将所有接收者地址都添加到邮件接收者属性中

            mailMessage.setRecipients(Message.RecipientType.TO, tos);

            mailMessage.setSubject(mailInfo.getSubject());

            mailMessage.setSentDate(new Date());

            // 设置邮件内容

            Multipart mainPart = new MimeMultipart();

            BodyPart html = new MimeBodyPart();

            html.setContent(mailInfo.getContent(), "text/html; charset=GBK");

            mainPart.addBodyPart(html);

            mailMessage.setContent(mainPart);

            // 发送邮件

            Transport.send(mailMessage);

            return true;

        } catch (MessagingException ex) {

            ex.printStackTrace();

        }

        return false;

    }

    /**

     * 发送带抄送的邮件

     * @param mailInfo    待发送邮件的消息

     * @return

     */

    public static boolean sendMailtoMultiCC(MultiMailSenderInfo mailInfo){

        MyAuthenticator authenticator = null;

        if (mailInfo.isValidate()) {

            authenticator = new MyAuthenticator(mailInfo.getUserName(),

                    mailInfo.getPassword());

        }

        Session sendMailSession = Session.getInstance(mailInfo

                .getProperties(), authenticator);

        try {

            Message mailMessage = new MimeMessage(sendMailSession);

            // 创建邮件发送者地址

            Address from = new InternetAddress(mailInfo.getFromAddress());

            mailMessage.setFrom(from);

            // 创建邮件的接收者地址，并设置到邮件消息中

            Address to = new InternetAddress(mailInfo.getToAddress());

            mailMessage.setRecipient(Message.RecipientType.TO, to);

            // 获取抄送者信息

            String[] ccs = mailInfo.getCcs();

            if (ccs != null){

                // 为每个邮件接收者创建一个地址

                Address[] ccAdresses = new InternetAddress[ccs.length];

                for (int i=0; i<ccs.length; i++){

                    ccAdresses[i] = new InternetAddress(ccs[i]);

                }

                // 将抄送者信息设置到邮件信息中，注意类型为Message.RecipientType.CC

                mailMessage.setRecipients(Message.RecipientType.CC, ccAdresses);

            } 

            mailMessage.setSubject(mailInfo.getSubject());

            mailMessage.setSentDate(new Date());

            // 设置邮件内容

            Multipart mainPart = new MimeMultipart();

            BodyPart html = new MimeBodyPart();

            html.setContent(mailInfo.getContent(), "text/html; charset=GBK");

            mainPart.addBodyPart(html);

            mailMessage.setContent(mainPart);

            // 发送邮件

            Transport.send(mailMessage);

            return true;

        } catch (MessagingException ex) {

            ex.printStackTrace();

        }

        return false;

    }

    public static void main(String[] args) {

        // 创建邮件信息

        MultiMailSenderInfo mailInfo = new MultiMailSenderInfo();

        mailInfo.setMailServerHost("smtp.sina.com.cn");

        mailInfo.setMailServerPort("25");

        mailInfo.setValidate(true);

        mailInfo.setUserName("***");

        mailInfo.setPassword("***");

        mailInfo.setFromAddress("***@sina.com");

        mailInfo.setToAddress("***@163.com");

        mailInfo.setSubject("MyMail测试");

        mailInfo.setContent("我的邮件测试/n/rMy test mail/n/r");

        String[] receivers = new String[]{"***@163.com", "***@tom.com"};

        String[] ccs = receivers;

        mailInfo.setReceivers(receivers);

        mailInfo.setCcs(ccs);

        MultiMailsender.sendMailtoMultiReceiver(mailInfo);

        MultiMailsender.sendMailtoMultiCC(mailInfo);

    }

    /**

     * 发送多接收者类型邮件的基本信息

     */

    public static class MultiMailSenderInfo extends MailSenderInfo{

        // 邮件的接收者，可以有多个

        private String[] receivers;

        // 邮件的抄送者，可以有多个

        private String[] ccs;

        public String[] getCcs() {

            return ccs;

        }

        public void setCcs(String[] ccs) {

            this.ccs = ccs;

        }

        public String[] getReceivers() {

            return receivers;

        }

        public void setReceivers(String[] receivers) {

            this.receivers = receivers;

        }

    }

}