java mail 发送邮件，线程安全

package com.tmg.aec.common.until;

import java.io.File;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Properties;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

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.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;

/**
 * @author duanzc
 * @date:2010-10-19 下午02:30:30
 * @version :1.0
 * @类说明：发送邮件，线程安全
 */
public class EmailSenderByThread extends MyThread{
	private static final String charset = "UTF-8";
	private static final String defaultMimetype = "text/plain";
	private static final String nickname = "看图说话";
	private static final String PORT = "25";

	private static final String SMTP = "ma.sai.ke";
	private static final String myEmailAddress = "ma.sai.ke";
	private static final String myEmailPWD = "ma.sai.ke";
	private static final String isVerification = "true";

	public static void main(String[] args) {
		String[] mails = new String[] {"635343934@qq.com",
		"duanzuocai@yahoo.com.cn", "duanzuocai@sohu.com",
		"duanzuocai@foxmail.com", "duanzuocai@gmail.com",
		"duanzuocai@hotmail.com", "duanzuocai@163.com",
		"duanzuocai@126.com","duanzuocai@sina.com"};
		
		String cont = "月圆之夜，紫荆之巅。一剑西来，天外飞仙。";
		
		try {
			for(String s:mails)
				EmailSenderByThread.send(s, "看图说话", cont, "text/html");
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	

	
	// ======================= 初始化线程 =============================
	// 参数
	String[] receivers;
	File[] attachements;
	String subject, mailContent, mimetype;
	
	/** 最多同时执行的任务数 */
	private static ExecutorService service = Executors.newFixedThreadPool(MyThread.getMaxThread());
	private static List<MyThread> threads = new ArrayList();
	
	static{
		for(int i = 0; i < MyThread.getMaxThread() + 1; i++){
			threads.add(new EmailSenderByThread());
		}
	}

	// ======================= 初始化线程 =============================
	
	@Override
	public void runCode() throws MessagingException, UnsupportedEncodingException {
		Properties props = new Properties();
		props.put("mail.smtp.port", PORT);				// 端口
		props.put("mail.smtp.host", SMTP);				// smtp服务器地址
		props.put("mail.smtp.auth", isVerification);	// 需要校验
		Session session = Session.getDefaultInstance(props,
				new Authenticator() {
					protected PasswordAuthentication getPasswordAuthentication() {
						return new PasswordAuthentication(myEmailAddress,
								myEmailPWD);			// 登录用户名/密码
					}
				});
		session.setDebug(true);
		MimeMessage mimeMessage = new MimeMessage(session);
		
		InternetAddress sender = new InternetAddress(myEmailAddress);
		
		sender.setPersonal(nickname, charset);			// 昵称（UTF-8编码）
		
		mimeMessage.setFrom(sender);					// 发件人邮件
		
		InternetAddress[] toAddress = new InternetAddress[receivers.length];
		
		for (int i = 0; i < receivers.length; i++) {
			toAddress[i] = new InternetAddress(receivers[i]);
		}
		
		mimeMessage.setRecipients(Message.RecipientType.TO, toAddress);// 收件人邮件
		mimeMessage.setSubject(subject, charset);

		Multipart multipart = new MimeMultipart();
		// 正文
		MimeBodyPart body = new MimeBodyPart();
		
		// body.setText(mailContent, charset);//不支持html
		body.setContent(mailContent,
				(mimetype != null && !"".equals(mimetype) ? mimetype
						: defaultMimetype)
						+ ";charset=" + charset);
		multipart.addBodyPart(body);// 发件内容
		// 附件
		if (attachements != null) {
			for (File attachement : attachements) {
				MimeBodyPart attache = new MimeBodyPart();
				attache.setDataHandler(new DataHandler(new FileDataSource(
						attachement)));
				String fileName = getLastName(attachement.getName());
				attache.setFileName(MimeUtility.encodeText(fileName, charset,
						null));
				multipart.addBodyPart(attache);
			}
		}
		mimeMessage.setContent(multipart);
		mimeMessage.setSentDate(new Date());
		
		Transport.send(mimeMessage);
	}

	@Override
	public void setArgs(Object... args) {
		this.receivers = (String[]) args[0];
		this.subject = args[1].toString();
		this.mailContent = args[2].toString();
		this.attachements = (File[]) args[3];
		this.mimetype = args[4].toString();
	}
	
	/**
	 * 发送邮件
	 * 
	 * @param receivers 收件人
	 * @param subject 标题
	 * @param mailContent 邮件内容
	 * @param attachements 附件
	 * @param mimetype 内容类型 默认为text/plain,如果要发送HTML内容,应设置为text/html
	 * @throws MessagingException
	 * @throws UnsupportedEncodingException
	 */
	public static void send(String[] receivers, String subject,
			String mailContent, File[] attachements, String mimetype)
			throws MessagingException, UnsupportedEncodingException {

		MyThread m = MyThread.getMyThread(threads, receivers, subject,
				mailContent, attachements, mimetype);
		service.execute(m);
	}

	/**
	 * 发送邮件
	 * 
	 * @param receiver 收件人
	 * @param subject 标题
	 * @param mailContent 邮件内容
	 * @param mimetype 内容类型 默认为text/plain,如果要发送HTML内容,应设置为text/html
	 * @throws MessagingException
	 * @throws UnsupportedEncodingException
	 */
	public static void send(String receiver, String subject,
			String mailContent, String mimetype)
			throws UnsupportedEncodingException, MessagingException {
		send(new String[] { receiver }, subject, mailContent, mimetype);
	}

	/**
	 * 发送邮件
	 * 
	 * @param receivers 收件人
	 * @param subject 标题
	 * @param mailContent 邮件内容
	 * @param mimetype 内容类型 默认为text/plain,如果要发送HTML内容,应设置为text/html
	 * @throws MessagingException
	 * @throws UnsupportedEncodingException
	 */
	public static void send(String[] receivers, String subject,
			String mailContent, String mimetype)
			throws UnsupportedEncodingException, MessagingException {
		send(receivers, subject, mailContent, null, mimetype);
	}

	private static String getLastName(String fileName) {
		int pos = fileName.lastIndexOf("\\");
		if (pos > -1) {
			fileName = fileName.substring(pos + 1);
		}
		pos = fileName.lastIndexOf("/");
		if (pos > -1) {
			fileName = fileName.substring(pos + 1);
		}
		return fileName;
	}
}

线程类：

package com.tmg.aec.common.until;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * @author duanzc
 * @date:2010-10-18 上午10:27:21
 * @version :1.0
 * @类说明：线程池
 */
@SuppressWarnings("unchecked")
public abstract class MyThread implements Runnable {
	/** 线程出错后重新运行次数 */
	private static int errorTimes = 2;

	/** 最多同时执行任务数 */
	private static int maxThread = 2;

	/** 线程使用状态：false未使用、true使用中 */
	private String thread_states = "false";
	


	/** 
	 * 得到空闲线程、并传递参数
	 * @param threads 线程池
	 * @param args 参数 
	 * @return
	 */
	protected static MyThread getMyThread(List<MyThread> threads, Object ... args) {
		for(MyThread t:threads){
			if(t.thread_states.equals("false")){
				t.thread_states = "true";	// 标记使用中
				t.setArgs(args);
				return t;
			}
		}
		try {
			Thread.sleep(1500L);
		} catch (Exception e) {
			e.printStackTrace();
		}

		return getMyThread(threads, args);
	}
	
	public void close(){
		this.thread_states = "false";
	}

	/** 执行代码 */
	public abstract void runCode() throws Exception;
	
	/** 设置参数 */
	public abstract void setArgs(Object ... args);;
	
	/** 异常获取、重新执行代码  */
	public void run() {
		try {
			runCode();
			this.close();
		} catch (Exception e) {
			e.printStackTrace();
			
			if(getErrorTimes()>0){
				setErrorTimes(getErrorTimes() - 1); 
				run();
			}
			this.close();
		}
	}	
	
	
	public static void main(String[] args) {
		ExecutorService service = Executors.newFixedThreadPool(2);
		
		List<MyThread> list = new ArrayList();
//		list.add(new MyThread());
		
		for(int i = 0; i < 1; i++){
			MyThread m = getMyThread(list, i+"",i+""+i);
			service.submit(m);
			m.close();
		}
	}

	// --------------------------------------

	public int getErrorTimes() {
		return errorTimes;
	}

	public void setErrorTimes(int errorTimes) {
		this.errorTimes = errorTimes;
	}

	public static int getMaxThread() {
		return maxThread;
	}

	public static void setMaxThread(int maxThread) {
		MyThread.maxThread = maxThread;
	}

	public String getThread_states() {
		return thread_states;
	}

	public void setThread_states(String threadStates) {
		thread_states = threadStates;
	}

}