使用JavaMail发送邮件需要用到mail.jar和activtion.jar两个包。

使用JavaMail发送邮件需要用到mail.jar和activtion.jar两个包。

该类实现了较完整的邮件发送功能，包括以HTML格式发送，添加附件和抄送人。下面是具体的代码：

Mail.java：

 

 package cn.cgw.util.mail;

 import java.util.Properties;

 import javax.activation.DataHandler;
 import javax.activation.FileDataSource;
 import javax.mail.Address;
 import javax.mail.BodyPart;
 import javax.mail.Message;
 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 Mail {

     private MimeMessage mimeMsg; //MIME邮件对象
     private Session session; //邮件会话对象
     private Properties props; //系统属性
     private boolean needAuth = false; //smtp是否需要认证
     //smtp认证用户名和密码
     private String username;
     private String password;
     private Multipart mp; //Multipart对象,邮件内容,标题,附件等内容均添加到其中后再生成MimeMessage对象

     /**
      * Constructor
      * @param smtp 邮件发送服务器
      */
     public Mail(String smtp){
         setSmtpHost(smtp);
         createMimeMessage();
     }

     /**
      * 设置邮件发送服务器
      * @param hostName String
      */
     public void setSmtpHost(String hostName) {
         System.out.println("设置系统属性：mail.smtp.host = "+hostName);
         if(props == null)
             props = System.getProperties(); //获得系统属性对象
         props.put("mail.smtp.host",hostName); //设置SMTP主机
     }


     /**
      * 创建MIME邮件对象
      * @return
      */
     public boolean createMimeMessage()
     {
         try {
             System.out.println("准备获取邮件会话对象！");
             session = Session.getDefaultInstance(props,null); //获得邮件会话对象
         }
         catch(Exception e){
             System.err.println("获取邮件会话对象时发生错误！"+e);
             return false;
         }

         System.out.println("准备创建MIME邮件对象！");
         try {
             mimeMsg = new MimeMessage(session); //创建MIME邮件对象
             mp = new MimeMultipart();

             return true;
         } catch(Exception e){
             System.err.println("创建MIME邮件对象失败！"+e);
             return false;
         }
     }

     /**
      * 设置SMTP是否需要验证
      * @param need
      */
     public void setNeedAuth(boolean need) {
         System.out.println("设置smtp身份认证：mail.smtp.auth = "+need);
         if(props == null) props = System.getProperties();
         if(need){
             props.put("mail.smtp.auth","true");
         }else{
             props.put("mail.smtp.auth","false");
         }
     }

     /**
      * 设置用户名和密码
      * @param name
      * @param pass
      */
     public void setNamePass(String name,String pass) {
         username = name;
         password = pass;
     }

     /**
      * 设置邮件主题
      * @param mailSubject
      * @return
      */
     public boolean setSubject(String mailSubject) {
         System.out.println("设置邮件主题！");
         try{
             mimeMsg.setSubject(mailSubject);
             return true;
         }
         catch(Exception e) {
             System.err.println("设置邮件主题发生错误！");
             return false;
         }
     }

     /**
      * 设置邮件正文
      * @param mailBody String
      */
     public boolean setBody(String mailBody) {
         try{
             BodyPart bp = new MimeBodyPart();
             bp.setContent(""+mailBody,"text/html;charset=GBK");
             mp.addBodyPart(bp);

             return true;
         } catch(Exception e){
         System.err.println("设置邮件正文时发生错误！"+e);
         return false;
         }
     }
     /**
      * 添加附件
      * @param filename String
      */
     public boolean addFileAffix(String filename) {

         System.out.println("增加邮件附件："+filename);
         try{
             BodyPart bp = new MimeBodyPart();
             FileDataSource fileds = new FileDataSource(filename);
             bp.setDataHandler(new DataHandler(fileds));
             bp.setFileName(fileds.getName());

             mp.addBodyPart(bp);

             return true;
         } catch(Exception e){
             System.err.println("增加邮件附件："+filename+"发生错误！"+e);
             return false;
         }
     }

     /**
      * 设置发信人
      * @param from String
      */
     public boolean setFrom(String from) {
         System.out.println("设置发信人！");
         try{
             mimeMsg.setFrom(new InternetAddress(from)); //设置发信人
             return true;
         } catch(Exception e) {
             return false;
         }
     }
     /**
      * 设置收信人
      * @param to String
      */
     public boolean setTo(String to){
         if(to == null)return false;
         try{
             mimeMsg.setRecipients(Message.RecipientType.TO,InternetAddress.parse(to));
             return true;
         } catch(Exception e) {
             return false;
         }
     }

     /**
      * 设置抄送人
      * @param copyto String
      */
     public boolean setCopyTo(String copyto)
     {
         if(copyto == null)return false;
         try{
         mimeMsg.setRecipients(Message.RecipientType.CC,(Address[])InternetAddress.parse(copyto));
         return true;
         }
         catch(Exception e)
         { return false; }
     }

     /**
      * 发送邮件
      */
     public boolean sendOut()
     {
         try{
             mimeMsg.setContent(mp);
             mimeMsg.saveChanges();
             System.out.println("正在发送邮件....");

             Session mailSession = Session.getInstance(props,null);
             Transport transport = mailSession.getTransport("smtp");
             transport.connect((String)props.get("mail.smtp.host"),username,password);
             transport.sendMessage(mimeMsg,mimeMsg.getRecipients(Message.RecipientType.TO));
             transport.sendMessage(mimeMsg,mimeMsg.getRecipients(Message.RecipientType.CC));
             //transport.send(mimeMsg);

             System.out.println("发送邮件成功！");
             transport.close();

             return true;
         } catch(Exception e) {
             System.err.println("邮件发送失败！"+e);
             return false;
         }
     }

     /**
      * 调用sendOut方法完成邮件发送
      * @param smtp
      * @param from
      * @param to
      * @param subject
      * @param content
      * @param username
      * @param password
      * @return boolean
      */
     public static boolean send(String smtp,String from,String to,String subject,String content,String username,String password) {
         Mail theMail = new Mail(smtp);
         theMail.setNeedAuth(true); //需要验证

         if(!theMail.setSubject(subject)) return false;
         if(!theMail.setBody(content)) return false;
         if(!theMail.setTo(to)) return false;
         if(!theMail.setFrom(from)) return false;
         theMail.setNamePass(username,password);

         if(!theMail.sendOut()) return false;
         return true;
     }

     /**
      * 调用sendOut方法完成邮件发送,带抄送
      * @param smtp
      * @param from
      * @param to
      * @param copyto
      * @param subject
      * @param content
      * @param username
      * @param password
      * @return boolean
      */
     public static boolean sendAndCc(String smtp,String from,String to,String copyto,String subject,String content,String username,String password) {
         Mail theMail = new Mail(smtp);
         theMail.setNeedAuth(true); //需要验证

         if(!theMail.setSubject(subject)) return false;
         if(!theMail.setBody(content)) return false;
         if(!theMail.setTo(to)) return false;
         if(!theMail.setCopyTo(copyto)) return false;
         if(!theMail.setFrom(from)) return false;
         theMail.setNamePass(username,password);

         if(!theMail.sendOut()) return false;
         return true;
     }

     /**
      * 调用sendOut方法完成邮件发送,带附件
      * @param smtp
      * @param from
      * @param to
      * @param subject
      * @param content
      * @param username
      * @param password
      * @param filename 附件路径
      * @return
      */
     public static boolean send(String smtp,String from,String to,String subject,String content,String username,String password,String filename) {
         Mail theMail = new Mail(smtp);
         theMail.setNeedAuth(true); //需要验证

         if(!theMail.setSubject(subject)) return false;
         if(!theMail.setBody(content)) return false;
         if(!theMail.addFileAffix(filename)) return false;
         if(!theMail.setTo(to)) return false;
         if(!theMail.setFrom(from)) return false;
         theMail.setNamePass(username,password);

         if(!theMail.sendOut()) return false;
         return true;
     }

     /**
      * 调用sendOut方法完成邮件发送,带附件和抄送
      * @param smtp
      * @param from
      * @param to
      * @param copyto
      * @param subject
      * @param content
      * @param username
      * @param password
      * @param filename
      * @return
      */
     public static boolean sendAndCc(String smtp,String from,String to,String copyto,String subject,String content,String username,String password,String filename) {
         Mail theMail = new Mail(smtp);
         theMail.setNeedAuth(true); //需要验证

         if(!theMail.setSubject(subject)) return false;
         if(!theMail.setBody(content)) return false;
         if(!theMail.addFileAffix(filename)) return false;
         if(!theMail.setTo(to)) return false;
         if(!theMail.setCopyTo(copyto)) return false;
         if(!theMail.setFrom(from)) return false;
         theMail.setNamePass(username,password);

         if(!theMail.sendOut()) return false;
         return true;
     }

 }

 测试代码：

 

 public static void main(String[] args){
     String smtp = "SMTP服务器";
     String from = "发信人";
     String to = "收信人";
     String copyto = "抄送人";
     String subject = "邮件主题";
     String content = "邮件内容";
     String username="用户名";
     String password="密码";
     String filename = "附件路径，如：F:\\笔记<a>\\struts2</a>与mvc.txt";
     Mail.sendAndCc(smtp, from, to, copyto, subject, content, username, password, filename);
 }