JavaMail实现SMTP客户端，由发送端服务器转发。

//Modified by zealvampire 07-4-4,排版

    JavaMail这个封装用起来也算方便，但如果是做界面的时候会发觉发送的时候你比较难跟踪它的过程，是在登陆验证密码还是正在发送；虽然可以设置session.setDebug(true)并且把输出流导向到UI界面，但是新版本的封装会把附件所有内容都打出来。。。建议要加点回调函数。

import java.io.File;
import java.io.PrintStream;
import java.util.*;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.*;
import javax.mail.event.TransportEvent;
import javax.mail.event.TransportListener;
import javax.mail.internet.*;

public class sendMails
    implements TransportListener
...{

    public sendMails()
    ...{
        authFlag = false;
        mimeType = "text/html";
        accessories = new ArrayList();
    }

    public void setUser(String user)
    ...{
        this.user = user;
    }

    public void setPassword(String password)
    ...{
        this.password = password;
    }

    public void setFromAddress(String fromAddress)
    ...{
        this.fromAddress = fromAddress;
    }

    public void setSmtpServerDns(String smtpServerDns)
    ...{
        this.smtpServerDns = smtpServerDns;
    }

    public void setAuthFlag(boolean authFlag)
    ...{
        this.authFlag = authFlag;
    }

    public void setReceiver(String receiver[])
    ...{
        this.receiver = receiver;
    }

    public void setTitle(String title)
    ...{
        this.title = title;
    }

    public void setContent(String content)
    ...{
        this.content = content;
    }

    public void setAccessories(ArrayList accessories)
    ...{
        this.accessories = accessories;
    }

    public void setMimeType(String mimeType)
    ...{
        this.mimeType = mimeType;
    }

    public void initSession()
    ...{
        Properties p = new Properties();
        p.put("mail.host", smtpServerDns);
        p.put("mail.smtp.auth", String.valueOf(authFlag));
        MailAuthenticator author = new MailAuthenticator(user, password);
        session = Session.getInstance(p, author);
        session.setDebug(true);
    }

    public void initMimeMessage()
    ...{
        if(session == null)
            initSession();
        mimeMesg = new MimeMessage(session);
        try
        ...{
            mimeMesg.setFrom(new InternetAddress(fromAddress));
            InternetAddress toAddress[] = new InternetAddress[receiver.length];
            for(int i = 0; i < receiver.length; i++)
                toAddress[i] = new InternetAddress(receiver[i]);

            mimeMesg.addRecipients(javax.mail.Message.RecipientType.TO, toAddress);
            mimeMesg.setSubject(title);
        }
        catch(MessagingException e)
        ...{
            e.printStackTrace();
        }
    }

    public void formMimeMessage()
    ...{
        if(mimeMesg == null)
            initMimeMessage();
        MimeMultipart mimeMultipart = new MimeMultipart();
        BodyPart contentBodyPart = new MimeBodyPart();
        StringBuffer contentBuf = new StringBuffer("<meta content=text/html; charset=gb2312>");
        contentBuf.append(content);
        try
        ...{
            contentBodyPart.setContent(contentBuf.toString(), "text/html;charset=GB2312");
            mimeMultipart.addBodyPart(contentBodyPart);
            if(!accessories.isEmpty())
            ...{
                MimeBodyPart fileBodyPart;
                for(Iterator it = accessories.iterator(); it.hasNext(); mimeMultipart.addBodyPart(fileBodyPart))
                ...{
                    String filePath = (String)it.next();
                    fileBodyPart = new MimeBodyPart();
                    FileDataSource fileDataSource = new FileDataSource(filePath);
                    fileBodyPart.setDataHandler(new DataHandler(fileDataSource));
                    fileBodyPart.setFileName(MimeUtility.encodeWord(fileDataSource.getName(), "GB2312", null));
                }

            }
            mimeMesg.setContent(mimeMultipart);
            mimeMesg.saveChanges();
            mimeMesg.setSentDate(new Date());
        }
        catch(MessagingException e)
        ...{
            e.printStackTrace();
        }
        catch(Exception ex)
        ...{
            ex.printStackTrace();
        }
    }

    public void send()
    ...{
        if(mimeMesg == null)
            formMimeMessage();
        try
        ...{
            Transport.send(mimeMesg);
            if(accessories != null && accessories.size() != 0)
            ...{
                for(int i = 0; i < accessories.size(); i++)
                ...{
                    File f = new File(accessories.get(i).toString());
                    f.delete();
                }

                accessories.clear();
            }
        }
        catch(Exception e)
        ...{
            e.printStackTrace();
        }
    }

    public void messageDelivered(TransportEvent event)
    ...{
        Address add[] = event.getValidSentAddresses();
        printEvent(event, add);
        System.out.println("以上地址成功发送.");
    }

    public void messageNotDelivered(TransportEvent event)
    ...{
        Address add[] = event.getValidUnsentAddresses();
        printEvent(event, add);
        System.out.println("以上合法地址未能发送.");
    }

    public void messagePartiallyDelivered(TransportEvent event)
    ...{
        Address add[] = event.getValidSentAddresses();
        printEvent(event, add);
        System.out.println("以上地址部分发送成功.");
    }

    public void printEvent(TransportEvent event, Address add[])
    ...{
        System.out.println("**************************************");
        System.out.println("evnet==" + event.getMessage().toString());
        if(add != null)
        ...{
            for(int i = 0; i < add.length; i++)
                System.out.println(add[i].toString());

        }
    }

    private String user;
    private String password;
    private String fromAddress;
    private String smtpServerDns;
    private boolean authFlag;
    private String receiver[];
    private String title;
    private String content;
    private String mimeType;
    private ArrayList accessories;
    private Session session;
    private MimeMessage mimeMesg;
}

------------------------------------------------------

import javax.mail.Authenticator;
import javax.mail.PasswordAuthentication;

public class MailAuthenticator extends Authenticator
...{

    public MailAuthenticator()
    ...{
        user = "";
        password = "";
    }

    public MailAuthenticator(String user, String password)
    ...{
        this.user = user;
        this.password = password;
    }

    public MailAuthenticator(String user)
    ...{
        this.user = user;
        password = "";
    }

    public PasswordAuthentication getPasswordAuthentication()
    ...{
        return new PasswordAuthentication(user, password);
    }

    private String user;
    private String password;
}