下载后解压，将mail.jar和activation.jar放到project里的lib文件夹中，为其配置环境变量，或在myEclipse里的"Java Build Path"中将其添加到"Libraries"。

project里有三个类：入口类(TestJavaMail)、邮件信息类(MailBean)和发送邮件类(SendMail)

MailBean.java

packagetest3;

importjava.util.Vector;

publicclassMailBean{

privateString to;//收件人privateString from;//发件人privateString host;//SMTP主机privateString username;//发件人的用户名privateString password;//发件人的密码privateString subject;//邮件主题privateString content;//邮件正文Vectorfile;//多个附件privateString filename;//附件的文件名publicString getTo(){

returnto;

    }

publicvoidsetTo(String to){

this.to=to;

    }

publicString getFrom(){

returnfrom;

    }

publicvoidsetFrom(String from){

this.from=from;

    }

publicString getHost(){

returnhost;

    }

publicvoidsetHost(String host){

this.host=host;

    }

publicString getUsername(){

returnusername;

    }

publicvoidsetUsername(String username){

this.username=username;

    }

publicString getPassword(){

returnpassword;

    }

publicvoidsetPassword(String password){

this.password=password;

    }

publicString getSubject(){

returnsubject;

    }

publicvoidsetSubject(String subject){

this.subject=subject;

    }

publicString getContent(){

returncontent;

    }

publicvoidsetContent(String content){

this.content=content;

    }

publicString getFilename(){

returnfilename;

    }

publicvoidsetFilename(String filename){

this.filename=filename;

    }

publicVectorgetFile(){

returnfile;

    }

publicvoidattachFile(String fileName){

if(file==null)

            file=newVector();

        file.addElement(fileName);

    }}

SendMail.java

packagetest3;

importjava.util.Date;

importjava.util.Enumeration;

importjava.util.Properties;

importjava.util.Vector;

importjavax.activation.DataHandler;

importjavax.activation.FileDataSource;

importjavax.mail.Authenticator;

importjavax.mail.Message;

importjavax.mail.MessagingException;

importjavax.mail.Multipart;

importjavax.mail.PasswordAuthentication;

importjavax.mail.Session;

importjavax.mail.Transport;

importjavax.mail.internet.InternetAddress;

importjavax.mail.internet.MimeBodyPart;

importjavax.mail.internet.MimeMessage;

importjavax.mail.internet.MimeMultipart;

importjavax.mail.internet.MimeUtility;

publicclassSendMail{

publicString toChinese(String text){

try{

            text=MimeUtility.encodeText(newString(text.getBytes(),"GB2312"),"GB2312","B");

        }catch(Exception e){

            e.printStackTrace();

        }returntext;

    }

publicbooleansendMail(MailBean mb){

        String host=mb.getHost();

finalString username=mb.getUsername();

finalString password=mb.getPassword();

        String from=mb.getFrom();

        String to=mb.getTo();

        String subject=mb.getSubject();

        String content=mb.getContent();

        String fileName=mb.getFilename();

        Vectorfile=mb.getFile();

        Properties props=System.getProperties();

        props.put("mail.smtp.host", host);//设置SMTP的主机props.put("mail.smtp.auth","true");//需要经过验证        Session session=Session.getInstance(props,newAuthenticator(){

publicPasswordAuthentication getPasswordAuthentication(){

returnnewPasswordAuthentication(username, password);

            }        });

try{

            MimeMessage msg=newMimeMessage(session);

            msg.setFrom(newInternetAddress(from));

            InternetAddress[] address={newInternetAddress(to)};

            msg.setRecipients(Message.RecipientType.TO, address);

            msg.setSubject(toChinese(subject));

            Multipart mp=newMimeMultipart();

            MimeBodyPart mbpContent=newMimeBodyPart();

            mbpContent.setText(content);

            mp.addBodyPart(mbpContent);

/*往邮件中添加附件*/            Enumerationefile=file.elements();

while(efile.hasMoreElements()){

                MimeBodyPart mbpFile=newMimeBodyPart();

                fileName=efile.nextElement().toString();

                FileDataSource fds=newFileDataSource(fileName);

                mbpFile.setDataHandler(newDataHandler(fds));

                mbpFile.setFileName(toChinese(fds.getName()));

                mp.addBodyPart(mbpFile);

            }

            msg.setContent(mp);

            msg.setSentDate(newDate());

            Transport.send(msg);

        }catch(MessagingException me){

            me.printStackTrace();

returnfalse;

        }returntrue;

    }

}

TestJavaMail.java

packagetest3;

publicclassTestJavaMail{

publicstaticvoidmain(String[] args){

        MailBean mb=newMailBean();

        mb.setHost("smtp.163.com");//设置SMTP主机(163)，若用126，则设为：smtp.126.commb.setUsername("linyiteng1220");//设置发件人邮箱的用户名mb.setPassword("******");//设置发件人邮箱的密码，需将*号改成正确的密码mb.setFrom("linyiteng1220@163.com");//设置发件人的邮箱mb.setTo("linyiteng1220@126.com");//设置收件人的邮箱mb.setSubject("测试_JavaMail");//设置邮件的主题mb.setContent("本邮件中包含三个附件，请检查！");//设置邮件的正文        mb.attachFile("E:/工作报告(林乙腾).doc");//往邮件中添加附件mb.attachFile("E:/test.txt");

        mb.attachFile("E:/test.xls");

        SendMail sm=newSendMail();

        System.out.println("正在发送邮件...");

if(sm.sendMail(mb))//发送邮件System.out.println("发送成功!");

else            System.out.println("发送失败!");

    }

}

如果你用myEclipse进行开发的话，运行时可能会出现以下的错误：

Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/mail/util/LineInputStream

解决方法：移除myEclipse自带的EE包

。

但你可能还需要用到EE包里的servlet相关类，那可以从Tomcat的lib文件夹中复制servlet-api.jar到project中，用它来代替EE包，一切OK！

另外，个人测试时发现无法通过新注册的网易邮箱来发邮件，以前旧的就没有问题，不知道是什么原因。

如果要通过gmail发邮件的话，请在代码Properties props = System.getProperties();后再添加以下两行代码：

props.put("mail.transport.protocol", "smtp");

props.put("mail.smtp.starttls.enable","true");

搞定！

如果存在缺漏和问题，请大家指正！