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;
        }
    }
}