下面是一个邮件接收的工具类，有点长！！！
public class ReciveMail { private MimeMessage msg = null; private String saveAttchPath = ""; private StringBuffer bodytext = new StringBuffer(); private String dateformate = "yy-MM-dd HH:mm"; public ReciveMail(MimeMessage msg){ this.msg = msg; } public void setMsg(MimeMessage msg) { this.msg = msg; } /** * 获取发送邮件者信息 * @return * @throws MessagingException */ public String getFrom() throws MessagingException{ InternetAddress[] address = (InternetAddress[]) msg.getFrom(); String from = address[0].getAddress(); if(from == null){ from = ""; } String personal = address[0].getPersonal(); if(personal == null){ personal = ""; } String fromaddr = personal +"<"+from+">"; return fromaddr; } /** * 获取邮件收件人，抄送，密送的地址和信息。根据所传递的参数不同 "to"-->收件人,"cc"-->抄送人地址,"bcc"-->密送地址 * @param type * @return * @throws MessagingException * @throws UnsupportedEncodingException */ public String getMailAddress(String type) throws MessagingException, UnsupportedEncodingException{ String mailaddr = ""; String addrType = type.toUpperCase(); InternetAddress[] address = null; if(addrType.equals("TO")||addrType.equals("CC")||addrType.equals("BCC")){ if(addrType.equals("TO")){ address = (InternetAddress[]) msg.getRecipients(Message.RecipientType.TO); } if(addrType.equals("CC")){ address = (InternetAddress[]) msg.getRecipients(Message.RecipientType.CC); } if(addrType.equals("BCC")){ address = (InternetAddress[]) msg.getRecipients(Message.RecipientType.BCC); } if(address != null){ for(int i=0;i<address.length;i++){ String mail = address[i].getAddress(); if(mail == null){ mail = ""; }else{ mail = MimeUtility.decodeText(mail); } String personal = address[i].getPersonal(); if(personal == null){ personal = ""; }else{ personal = MimeUtility.decodeText(personal); } String compositeto = personal +"<"+mail+">"; mailaddr += ","+compositeto; } mailaddr = mailaddr.substring(1); } }else{ throw new RuntimeException("Error email Type!"); } return mailaddr; } /** * 获取邮件主题 * @return * @throws UnsupportedEncodingException * @throws MessagingException */ public String getSubject() throws UnsupportedEncodingException, MessagingException{ String subject = ""; subject = MimeUtility.decodeText(msg.getSubject()); if(subject == null){ subject = ""; } return subject; } /** * 获取邮件发送日期 * @return * @throws MessagingException */ public String getSendDate() throws MessagingException{ Date sendDate = msg.getSentDate(); SimpleDateFormat smd = new SimpleDateFormat(dateformate); return smd.format(sendDate); } /** * 获取邮件正文内容 * @return */ public String getBodyText(){ return bodytext.toString(); } /** * 解析邮件，将得到的邮件内容保存到一个stringBuffer对象中， * 解析邮件 主要根据MimeType的不同执行不同的操作，一步一步的解析 * @param part * @throws MessagingException * @throws IOException */ public void getMailContent(Part part) throws MessagingException, IOException{ String contentType = part.getContentType(); int nameindex = contentType.indexOf("name"); boolean conname = false; if(nameindex != -1){ conname = true; } System.out.println("CONTENTTYPE:"+contentType); if(part.isMimeType("text/plain")&&!conname){ bodytext.append((String)part.getContent()); }else if(part.isMimeType("text/html")&&!conname){ bodytext.append((String)part.getContent()); }else if(part.isMimeType("multipart/*")){ Multipart multipart = (Multipart) part.getContent(); int count = multipart.getCount(); for(int i=0;i<count;i++){ getMailContent(multipart.getBodyPart(i)); } }else if(part.isMimeType("message/rfc822")){ getMailContent((Part) part.getContent()); } } /** * 判断邮件是否需要回执，如需回执返回true，否则返回false * @return * @throws MessagingException */ public boolean getReplySign() throws MessagingException{ boolean replySign = false; String needreply[] = msg.getHeader("Disposition-Notification-TO"); if(needreply != null){ replySign = true; } return replySign; } /** * 获取此邮件的message-id * @return * @throws MessagingException */ public String getMessageId() throws MessagingException{ return msg.getMessageID(); } /** * 判断此邮件是否已读，如果未读则返回false，已读返回true * @return * @throws MessagingException */ public boolean isNew() throws MessagingException{ boolean isnew = false; Flags flags = ((Message)msg).getFlags(); Flags.Flag[] flag = flags.getSystemFlags(); System.out.println("flags's length:"+flag.length); for(int i=0;i<flag.length;i++){ if(flag[i]==Flags.Flag.SEEN){ isnew = true; System.out.println("seen message ......."); break; } } return isnew; } /** * 判断是是否包含附件 * @param part * @return * @throws MessagingException * @throws IOException */ public boolean isContainAttch(Part part) throws MessagingException, IOException{ boolean flag = false; //String contentType = part.getContentType(); if(part.isMimeType("multipart/*")){ Multipart multipart = (Multipart) part.getContent(); int count = multipart.getCount(); for(int i=0;i<count;i++){ BodyPart bodypart = multipart.getBodyPart(i); String dispostion = bodypart.getDisposition(); if((dispostion != null)&&(dispostion.equals(Part.ATTACHMENT)||dispostion.equals(Part.INLINE))){ flag = true; }else if(bodypart.isMimeType("multipart/*")){ flag = isContainAttch(bodypart); }else{ String conType = bodypart.getContentType(); if(conType.toLowerCase().indexOf("appliaction")!=-1){ flag = true; } if(conType.toLowerCase().indexOf("name")!=-1){ flag = true; } } } }else if(part.isMimeType("message/rfc822")){ flag = isContainAttch((Part) part.getContent()); } return flag; } /** * 保存附件 * @param part * @throws MessagingException * @throws IOException */ public void saveAttchMent(Part part) throws MessagingException, IOException{ String filename = ""; if(part.isMimeType("multipart/*")){ Multipart mp = (Multipart) part.getContent(); for(int i=0;i<mp.getCount();i++){ BodyPart mpart = mp.getBodyPart(i); String dispostion = mpart.getDisposition(); if((dispostion != null)&&(dispostion.equals(Part.ATTACHMENT)||dispostion.equals(Part.INLINE))){ filename = mpart.getFileName(); if(filename.toLowerCase().indexOf("gb2312")!=-1){ filename = MimeUtility.decodeText(filename); } saveFile(filename,mpart.getInputStream()); }else if(mpart.isMimeType("multipart/*")){ saveAttchMent(mpart); }else{ filename = mpart.getFileName(); if(filename != null&&(filename.toLowerCase().indexOf("gb2312")!=-1)){ filename = MimeUtility.decodeText(filename); } saveFile(filename,mpart.getInputStream()); } } }else if(part.isMimeType("message/rfc822")){ saveAttchMent((Part) part.getContent()); } } /** * 获得保存附件的地址 * @return */ public String getSaveAttchPath() { return saveAttchPath; } /** * 设置保存附件地址 * @param saveAttchPath */ public void setSaveAttchPath(String saveAttchPath) { this.saveAttchPath = saveAttchPath; } /** * 设置日期格式 * @param dateformate */ public void setDateformate(String dateformate) { this.dateformate = dateformate; } /** * 保存文件内容 * @param filename * @param inputStream * @throws IOException */ private void saveFile(String filename, InputStream inputStream) throws IOException { String osname = System.getProperty("os.name"); String storedir = getSaveAttchPath(); String sepatror = ""; if(osname == null){ osname = ""; } if(osname.toLowerCase().indexOf("win")!=-1){ sepatror = "//"; if(storedir==null||"".equals(storedir)){ storedir = "d://temp"; } }else{ sepatror = "/"; storedir = "/temp"; } File storefile = new File(storedir+sepatror+filename); System.out.println("storefile's path:"+storefile.toString()); BufferedOutputStream bos = null; BufferedInputStream bis = null; try { bos = new BufferedOutputStream(new FileOutputStream(storefile)); bis = new BufferedInputStream(inputStream); int c; while((c= bis.read())!=-1){ bos.write(c); bos.flush(); } } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{ bos.close(); bis.close(); } } public void recive(Part part,int i) throws MessagingException, IOException{ System.out.println("------------------START-----------------------"); System.out.println("Message"+i+" subject:" + getSubject()); System.out.println("Message"+i+" from:" + getFrom()); System.out.println("Message"+i+" isNew:" + isNew()); boolean flag = isContainAttch(part); System.out.println("Message"+i+" isContainAttch:" +flag); System.out.println("Message"+i+" replySign:" + getReplySign()); getMailContent(part); System.out.println("Message"+i+" content:" + getBodyText()); setSaveAttchPath("c://temp//"+i); if(flag){ saveAttchMent(part); } System.out.println("------------------END-----------------------"); }}邮件接收与工具类的使用，有好几种邮件接收的写法！：
看了很多网上其他代码，pop3Server的值是pop.mail.163.com，但是试了试不成功，还有 user的值既可以是带有 [email protected]也可以是username。
如果收件邮箱是163邮箱，必须先登陆163邮箱中设置，开启pop3服务。至于别的邮箱暂不知道。
public static void main(String[] args) throws Exception { // 连接pop3服务器的主机名、协议、用户名、密码 String pop3Server = "pop.163.com"; String protocol = "pop3"; String user = "username"; String pwd = "password"; // 创建一个有具体连接信息的Properties对象 Properties props = new Properties(); props.setProperty("mail.store.protocol", protocol); props.setProperty("mail.pop3.host", pop3Server); // 使用Properties对象获得Session对象 Session session = Session.getInstance(props); session.setDebug(true); // 利用Session对象获得Store对象，并连接pop3服务器 Store store = session.getStore(); store.connect(pop3Server, user, pwd); // 获得邮箱内的邮件夹Folder对象，以"只读"打开 Folder folder = store.getFolder("inbox"); folder.open(Folder.READ_ONLY); // 获得邮件夹Folder内的所有邮件Message对象 Message [] messages = folder.getMessages(); ReciveMail rm = null; for(int i=0;i< messages.size() ;i++){ rm = new ReciveMail((MimeMessage) messages[i]); rm.recive(messages[i],i);; } folder.close(false); store.close(); }