JavaMail学习札记（四）、使用POP3协议接收并解析电子邮件（全）

JavaMail学习笔记（四）、使用POP3协议接收并解析电子邮件（全）

package org.yangxin.study.jm; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.UnsupportedEncodingException; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Properties; import javax.mail.Address; import javax.mail.BodyPart; import javax.mail.Flags; import javax.mail.Folder; import javax.mail.Message; import javax.mail.MessagingException; import javax.mail.Multipart; import javax.mail.Part; import javax.mail.Session; import javax.mail.Store; import javax.mail.internet.InternetAddress; import javax.mail.internet.MimeMessage; import javax.mail.internet.MimeMultipart; import javax.mail.internet.MimeUtility; /** * 使用POP3协议接收邮件 */ public class POP3ReceiveMailTest { public static void main(String[] args) throws Exception { receive(); } /** * 接收邮件 */ public static void receive() throws Exception { // 准备连接服务器的会话信息 Properties props = new Properties(); props.setProperty("mail.store.protocol", "pop3"); // 协议 props.setProperty("mail.pop3.port", "110"); // 端口 props.setProperty("mail.pop3.host", "pop3.163.com"); // pop3服务器 // 创建Session实例对象 Session session = Session.getInstance(props); Store store = session.getStore("pop3"); store.connect("xyang0917@163.com", "123456abc"); // 获得收件箱 Folder folder = store.getFolder("INBOX"); /* Folder.READ_ONLY：只读权限 * Folder.READ_WRITE：可读可写（可以修改邮件的状态） */ folder.open(Folder.READ_WRITE); //打开收件箱 // 由于POP3协议无法获知邮件的状态,所以getUnreadMessageCount得到的是收件箱的邮件总数 System.out.println("未读邮件数: " + folder.getUnreadMessageCount()); // 由于POP3协议无法获知邮件的状态,所以下面得到的结果始终都是为0 System.out.println("删除邮件数: " + folder.getDeletedMessageCount()); System.out.println("新邮件: " + folder.getNewMessageCount()); // 获得收件箱中的邮件总数 System.out.println("邮件总数: " + folder.getMessageCount()); // 得到收件箱中的所有邮件,并解析 Message[] messages = folder.getMessages(); parseMessage(messages); //释放资源 folder.close(true); store.close(); } /** * 解析邮件 * @param messages 要解析的邮件列表 */ public static void parseMessage(Message ...messages) throws MessagingException, IOException { if (messages == null || messages.length < 1) throw new MessagingException("未找到要解析的邮件!"); // 解析所有邮件 for (int i = 0, count = messages.length; i < count; i++) { MimeMessage msg = (MimeMessage) messages[i]; System.out.println("------------------解析第" + msg.getMessageNumber() + "封邮件-------------------- "); System.out.println("主题: " + getSubject(msg)); System.out.println("发件人: " + getFrom(msg)); System.out.println("收件人：" + getReceiveAddress(msg, null)); System.out.println("发送时间：" + getSentDate(msg, null)); System.out.println("是否已读：" + isSeen(msg)); System.out.println("邮件优先级：" + getPriority(msg)); System.out.println("是否需要回执：" + isReplySign(msg)); System.out.println("邮件大小：" + msg.getSize() * 1024 + "kb"); boolean isContainerAttachment = isContainAttachment(msg); System.out.println("是否包含附件：" + isContainerAttachment); if (isContainerAttachment) { saveAttachment(msg, "c:\\mailtmp\\"+msg.getSubject() + "_"); //保存附件 } StringBuffer content = new StringBuffer(30); getMailTextContent(msg, content); System.out.println("邮件正文：" + (content.length() > 100 ? content.substring(0,100) + "..." : content)); System.out.println("------------------第" + msg.getMessageNumber() + "封邮件解析结束-------------------- "); System.out.println(); } } /** * 获得邮件主题 * @param msg 邮件内容 * @return 解码后的邮件主题 */ public static String getSubject(MimeMessage msg) throws UnsupportedEncodingException, MessagingException { return MimeUtility.decodeText(msg.getSubject()); } /** * 获得邮件发件人 * @param msg 邮件内容 * @return 姓名 <Email地址> * @throws MessagingException * @throws UnsupportedEncodingException */ public static String getFrom(MimeMessage msg) throws MessagingException, UnsupportedEncodingException { String from = ""; Address[] froms = msg.getFrom(); if (froms.length < 1) throw new MessagingException("没有发件人!"); InternetAddress address = (InternetAddress) froms[0]; String person = address.getPersonal(); if (person != null) { person = MimeUtility.decodeText(person) + " "; } else { person = ""; } from = person + "<" + address.getAddress() + ">"; return from; } /** * 根据收件人类型，获取邮件收件人、抄送和密送地址。如果收件人类型为空，则获得所有的收件人 * <p>Message.RecipientType.TO 收件人</p> * <p>Message.RecipientType.CC 抄送</p> * <p>Message.RecipientType.BCC 密送</p> * @param msg 邮件内容 * @param type 收件人类型 * @return 收件人1 <邮件地址1>, 收件人2 <邮件地址2>, ... * @throws MessagingException */ public static String getReceiveAddress(MimeMessage msg, Message.RecipientType type) throws MessagingException { StringBuffer receiveAddress = new StringBuffer(); Address[] addresss = null; if (type == null) { addresss = msg.getAllRecipients(); } else { addresss = msg.getRecipients(type); } if (addresss == null || addresss.length < 1) throw new MessagingException("没有收件人!"); for (Address address : addresss) { InternetAddress internetAddress = (InternetAddress)address; receiveAddress.append(internetAddress.toUnicodeString()).append(","); } receiveAddress.deleteCharAt(receiveAddress.length()-1); //删除最后一个逗号 return receiveAddress.toString(); } /** * 获得邮件发送时间 * @param msg 邮件内容 * @return yyyy年mm月dd日 星期X HH:mm * @throws MessagingException */ public static String getSentDate(MimeMessage msg, String pattern) throws MessagingException { Date receivedDate = msg.getSentDate(); if (receivedDate == null) return ""; if (pattern == null || "".equals(pattern)) pattern = "yyyy年MM月dd日 E HH:mm "; return new SimpleDateFormat(pattern).format(receivedDate); } /** * 判断邮件中是否包含附件 * @param msg 邮件内容 * @return 邮件中存在附件返回true，不存在返回false * @throws MessagingException * @throws IOException */ public static boolean isContainAttachment(Part part) throws MessagingException, IOException { boolean flag = false; if (part.isMimeType("multipart/*")) { MimeMultipart multipart = (MimeMultipart) part.getContent(); int partCount = multipart.getCount(); for (int i = 0; i < partCount; i++) { BodyPart bodyPart = multipart.getBodyPart(i); String disp = bodyPart.getDisposition(); if (disp != null && (disp.equalsIgnoreCase(Part.ATTACHMENT) || disp.equalsIgnoreCase(Part.INLINE))) { flag = true; } else if (bodyPart.isMimeType("multipart/*")) { flag = isContainAttachment(bodyPart); } else { String contentType = bodyPart.getContentType(); if (contentType.indexOf("application") != -1) { flag = true; } if (contentType.indexOf("name") != -1) { flag = true; } } if (flag) break; } } else if (part.isMimeType("message/rfc822")) { flag = isContainAttachment((Part)part.getContent()); } return flag; } /** * 判断邮件是否已读 * @param msg 邮件内容 * @return 如果邮件已读返回true,否则返回false * @throws MessagingException */ public static boolean isSeen(MimeMessage msg) throws MessagingException { return msg.getFlags().contains(Flags.Flag.SEEN); } /** * 判断邮件是否需要阅读回执 * @param msg 邮件内容 * @return 需要回执返回true,否则返回false * @throws MessagingException */ public static boolean isReplySign(MimeMessage msg) throws MessagingException { boolean replySign = false; String[] headers = msg.getHeader("Disposition-Notification-To"); if (headers != null) replySign = true; return replySign; } /** * 获得邮件的优先级 * @param msg 邮件内容 * @return 1(High):紧急 3:普通(Normal) 5:低(Low) * @throws MessagingException */ public static String getPriority(MimeMessage msg) throws MessagingException { String priority = "普通"; String[] headers = msg.getHeader("X-Priority"); if (headers != null) { String headerPriority = headers[0]; if (headerPriority.indexOf("1") != -1 || headerPriority.indexOf("High") != -1) priority = "紧急"; else if (headerPriority.indexOf("5") != -1 || headerPriority.indexOf("Low") != -1) priority = "低"; else priority = "普通"; } return priority; } /** * 获得邮件文本内容 * @param part 邮件体 * @param content 存储邮件文本内容的字符串 * @throws MessagingException * @throws IOException */ public static void getMailTextContent(Part part, StringBuffer content) throws MessagingException, IOException { //如果是文本类型的附件，通过getContent方法可以取到文本内容，但这不是我们需要的结果，所以在这里要做判断 boolean isContainTextAttach = part.getContentType().indexOf("name") > 0; if (part.isMimeType("text/*") && !isContainTextAttach) { content.append(part.getContent().toString()); } else if (part.isMimeType("message/rfc822")) { getMailTextContent((Part)part.getContent(),content); } else if (part.isMimeType("multipart/*")) { Multipart multipart = (Multipart) part.getContent(); int partCount = multipart.getCount(); for (int i = 0; i < partCount; i++) { BodyPart bodyPart = multipart.getBodyPart(i); getMailTextContent(bodyPart,content); } } } /** * 保存附件 * @param part 邮件中多个组合体中的其中一个组合体 * @param destDir 附件保存目录 * @throws UnsupportedEncodingException * @throws MessagingException * @throws FileNotFoundException * @throws IOException */ public static void saveAttachment(Part part, String destDir) throws UnsupportedEncodingException, MessagingException, FileNotFoundException, IOException { if (part.isMimeType("multipart/*")) { Multipart multipart = (Multipart) part.getContent(); //复杂体邮件 //复杂体邮件包含多个邮件体 int partCount = multipart.getCount(); for (int i = 0; i < partCount; i++) { //获得复杂体邮件中其中一个邮件体 BodyPart bodyPart = multipart.getBodyPart(i); //某一个邮件体也有可能是由多个邮件体组成的复杂体 String disp = bodyPart.getDisposition(); if (disp != null && (disp.equalsIgnoreCase(Part.ATTACHMENT) || disp.equalsIgnoreCase(Part.INLINE))) { InputStream is = bodyPart.getInputStream(); saveFile(is, destDir, decodeText(bodyPart.getFileName())); } else if (bodyPart.isMimeType("multipart/*")) { saveAttachment(bodyPart,destDir); } else { String contentType = bodyPart.getContentType(); if (contentType.indexOf("name") != -1 || contentType.indexOf("application") != -1) { saveFile(bodyPart.getInputStream(), destDir, decodeText(bodyPart.getFileName())); } } } } else if (part.isMimeType("message/rfc822")) { saveAttachment((Part) part.getContent(),destDir); } } /** * 读取输入流中的数据保存至指定目录 * @param is 输入流 * @param fileName 文件名 * @param destDir 文件存储目录 * @throws FileNotFoundException * @throws IOException */ private static void saveFile(InputStream is, String destDir, String fileName) throws FileNotFoundException, IOException { BufferedInputStream bis = new BufferedInputStream(is); BufferedOutputStream bos = new BufferedOutputStream( new FileOutputStream(new File(destDir + fileName))); int len = -1; while ((len = bis.read()) != -1) { bos.write(len); bos.flush(); } bos.close(); bis.close(); } /** * 文本解码 * @param encodeText 解码MimeUtility.encodeText(String text)方法编码后的文本 * @return 解码后的文本 * @throws UnsupportedEncodingException */ public static String decodeText(String encodeText) throws UnsupportedEncodingException { if (encodeText == null || "".equals(encodeText)) { return ""; } else { return MimeUtility.decodeText(encodeText); } } }测试结果：