java电子邮件(三)

最新的JavaMail 1.3.1增强了在国际化字符集的处理，很多原来的关于中文的问题都可以迎刃而解，下面是一个例子用来收取邮箱中的所有邮件，包括内容附件等。经过试验：标题，内容，发件人名，中文附件都可以正确处理！大家测试的时候请下载最新的JavaMail包以及Java Activation Framework(JAF,activation.jar)，然后需要修改一下在main方法中的邮箱地址以及帐号，代码如下：
/*
Created on 2004-7-5
*/
package demo;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import javax.mail.BodyPart;
import javax.mail.FetchProfile;
import javax.mail.Folder;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.Session;
import javax.mail.Store;
import javax.mail.UIDFolder;
import javax.mail.URLName;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeUtility;
import com.sun.mail.pop3.POP3Folder;
/**
* 邮件接收演示例子
@author liudong
*/
public class MailFetcher {
/**
使用默认的110端口收取邮件
   * @param host
@param user
   * @param password
@return
   * @throws IOException
   * @throws MessagingException
   */
public static void listMails(String host,String user,String password)
    throws IOException, MessagingException {
   listMails(host,110,user,password);
}
/**
接收指定帐号的所有邮件概要信息(不包括内容和附件)
@param account
   * @return
   * @throws MessagingException
   * @throws UnsupportedEncodingException
   */
public static void listMails(String host,int port,String user,String password)    throws IOException, MessagingException {
   //pop3必须小写
   URLName url = new URLName("pop3", host, port, "", user, password);
   Session session = Session.getDefaultInstance(System.getProperties(),null);
   Store store = session.getStore(url);
   POP3Folder inbox = null;
   try {
    store.connect();
    inbox = (POP3Folder) store.getFolder("INBOX");
    inbox.open(Folder.READ_ONLY);
    FetchProfile profile = new FetchProfile();
    profile.add(UIDFolder.FetchProfileItem.UID); 
    profile.add(FetchProfile.Item.ENVELOPE);
    Message[] messages = inbox.getMessages();
    inbox.fetch(messages, profile);
    for (int i = 0; i < messages.length; i++) {
//邮件发送者
     String from = decodeText(messages[i].getFrom()[0].toString());
     InternetAddress ia = new InternetAddress(from);
     System.out.println("FROM:"+ia.getPersonal());
     //邮件发送者地址
     System.out.println("FROM_ADDR:"+ia.getAddress());
     //邮件标题
     System.out.println("TITLE:"+messages[i].getSubject());
     //邮件的唯一标识信息
     System.out.println("UID:"+inbox.getUID(messages[i]));
     //邮件大小
     System.out.println("SIZE:"+messages[i].getSize());
     //邮件发送时间
     System.out.println("DATE:"+messages[i].getSentDate());
     //读取邮件内容
     Object content = messages[i].getContent();
     if(content instanceof String)
      System.out.println("CONTENT:"+content);  
     Else
     if(content instanceof Multipart)  
      dumpMultipart((Multipart)content);
    }
   } finally {
    try{
     inbox.close(false);
    }catch(Exception e){}
    try{
     store.close();
    }catch(Exception e){}
   }
}

protected static String decodeText(String text) throws UnsupportedEncodingException{
   if(text==null)
    return null;
   if (text.startsWith("=?GB") || text.startsWith("=?gb"))
    text = MimeUtility.decodeText(text);
   else
    text = new String(text.getBytes("ISO8859_1")); 
   return text; 
}

protected static void dumpMultipart(Multipart mmp) throws MessagingException, IOException{
   //System.out.println("ContentType:"+mmp.getContentType());
   for(int pc=0;pc<mmp.getCount();pc++){
    BodyPart bp = mmp.getBodyPart(pc);
    Object content = bp.getContent();
    if(content instanceof String){
     System.out.println("CONTENT:"+content);
    }
    else
    if(content instanceof Multipart)
     dumpMultipart((Multipart)content);
    else
    if(content instanceof InputStream)
     System.out.println("FileName:"+decodeText(bp.getFileName()));  
   }
}
public static void main(String[] args) throws IOException, MessagingException {
   listMails("邮件服务器地址","帐号","密码");
}
}