利用JavaMail实现邮件的收取
???? 昨天写了一个利用JavaMail发送邮件的示例，本着有始有终的原则。今天写了一篇利用JavaMail收取邮件的示例。由于实力有限，代码写的不周到的地方，请大家见亮。本人只是写了一个简单的例子，在实际项目开发中，还有很多东西需要读者自己去斟酌和修改。废话不多说，直接上代码。
1、一些参数配置的常量类
package com.bao.receivemail;/** * 邮件配置的常量类 */public class Config {public static String MAIL_HOST = "pop3.163.com";//服务器ippublic static int MAIL_PORT = 110;//端口public static String MAIL_TYPE = "pop3";//服务类型public static String MAIL_AUTH = "true";public static String MAIL_ATTACH_PATH = "upload/recMail/";//附件存放目录}2、邮件的收取类
package com.bao.receivemail;import java.io.BufferedInputStream;import java.io.BufferedOutputStream;import java.io.File;import java.io.FileOutputStream;import java.io.InputStream;import java.text.SimpleDateFormat;import java.util.Properties;import javax.mail.BodyPart;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.URLName;import javax.mail.internet.InternetAddress;import javax.mail.internet.MimeMessage;import javax.mail.internet.MimeUtility;import com.sun.mail.pop3.POP3Message;/** * 邮件的收取类 */public class ReceiveMailHandler { /** * 获取session会话的方法 * @return * @throws Exception */ private Session getSessionMail() throws Exception { Properties properties = System.getProperties(); properties.put("mail.smtp.host", Config.MAIL_HOST); properties.put("mail.smtp.auth", Config.MAIL_AUTH); Session sessionMail = Session.getDefaultInstance(properties, null); return sessionMail; } /** * 接收邮件 * @param 邮箱的用户名和密码 * @return 无 */public void receiveMail(String userName,String passWord) { Store store = null; Folder folder = null; int messageCount = 0; URLName urln = null;try{//进行用户邮箱连接urln = new URLName(Config.MAIL_TYPE, Config.MAIL_HOST, Config.MAIL_PORT, null,userName,passWord); store = getSessionMail().getStore(urln); store.connect();//获得邮箱内的邮件夹Folder对象，以"只读"打开folder = store.getFolder("INBOX");//打开收件箱folder.open(Folder.READ_ONLY);//设置只读//获得邮件夹Folder内的所有邮件个数messageCount = folder.getMessageCount();// 获取所有邮件个数 //获取新邮件处理System.out.println("============>>邮件总数："+messageCount);if(messageCount > 0){Message[] messages = folder.getMessages(messageCount,messageCount);//读取最近的一封邮件for(int i = 0;i < messages.length;i++) {String content = getMailContent((Part)messages[i]);//获取内容 if (isContainAttach((Part)messages[i])) { saveAttachMent((Part)messages[i],Config.MAIL_ATTACH_PATH); } System.out.println("=====================>>开始显示邮件内容<<====================="); System.out.println("发送人: " + getFrom(messages[i])); System.out.println("主题: " + getSubject(messages[i])); System.out.println("内容: " + content); System.out.println("发送时间: " + new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(((MimeMessage) messages[i]).getSentDate())); System.out.println("是否有附件: " + (isContainAttach((Part)messages[i]) ? "有附件" : "无附件")); System.out.println("=====================>>结束显示邮件内容<<====================="); ((POP3Message) messages[i]).invalidate(true);}}}catch(Exception e){e.printStackTrace();}finally{if(folder != null && folder.isOpen()){try {folder.close(true);} catch (MessagingException e) {e.printStackTrace();}}if(store.isConnected()){try {store.close();} catch (MessagingException e) {e.printStackTrace();}}} } /** * 获得发件人的地址 * @param message：Message * @return 发件人的地址 */private String getFrom(Message message) throws Exception { InternetAddress[] address = (InternetAddress[]) ((MimeMessage) message).getFrom(); String from = address[0].getAddress(); if (from == null){ from = ""; } return from; } /** * 获得邮件主题 * @param message：Message * @return 邮件主题 */private String getSubject(Message message) throws Exception { String subject = ""; if(((MimeMessage) message).getSubject() != null){ subject = MimeUtility.decodeText(((MimeMessage) message).getSubject());// 将邮件主题解码 } return subject; } /** * 获取邮件内容 * @param part：Part */private String getMailContent(Part part) throws Exception { StringBuffer bodytext = new StringBuffer();//存放邮件内容//判断邮件类型,不同类型操作不同if (part.isMimeType("text/plain")) { bodytext.append((String) part.getContent()); } else if (part.isMimeType("text/html")) { bodytext.append((String) part.getContent()); } else if (part.isMimeType("multipart/*")) { Multipart multipart = (Multipart) part.getContent(); int counts = multipart.getCount(); for (int i = 0; i < counts; i++) { getMailContent(multipart.getBodyPart(i)); } } else if (part.isMimeType("message/rfc822")) { getMailContent((Part) part.getContent()); } else {} return bodytext.toString(); } /** * 判断此邮件是否包含附件 * @param part：Part * @return 是否包含附件 */private boolean isContainAttach(Part part) throws Exception { boolean attachflag = false; if (part.isMimeType("multipart/*")) { Multipart mp = (Multipart) part.getContent(); for (int i = 0; i < mp.getCount(); i++) { BodyPart mpart = mp.getBodyPart(i); String disposition = mpart.getDisposition(); if ((disposition != null) && ((disposition.equals(Part.ATTACHMENT)) || (disposition.equals(Part.INLINE)))) attachflag = true; else if (mpart.isMimeType("multipart/*")) { attachflag = isContainAttach((Part) mpart); } else { String contype = mpart.getContentType(); if (contype.toLowerCase().indexOf("application") != -1) attachflag = true; if (contype.toLowerCase().indexOf("name") != -1) attachflag = true; } } } else if (part.isMimeType("message/rfc822")) { attachflag = isContainAttach((Part) part.getContent()); } return attachflag; } /** * 保存附件 * @param part：Part * @param filePath：邮件附件存放路径 */private void saveAttachMent(Part part,String filePath) throws Exception { String fileName = ""; //保存附件到服务器本地 if (part.isMimeType("multipart/*")) { Multipart mp = (Multipart) part.getContent(); for (int i = 0; i < mp.getCount(); i++) { BodyPart mpart = mp.getBodyPart(i); String disposition = mpart.getDisposition(); if ((disposition != null) && ((disposition.equals(Part.ATTACHMENT)) || (disposition.equals(Part.INLINE)))) { fileName = mpart.getFileName(); if (fileName != null) { fileName = MimeUtility.decodeText(fileName); saveFile(fileName, mpart.getInputStream(),filePath); } } else if (mpart.isMimeType("multipart/*")) { saveAttachMent(mpart,filePath); } else { fileName = mpart.getFileName(); if (fileName != null) { fileName = MimeUtility.decodeText(fileName); saveFile(fileName, mpart.getInputStream(),filePath); } } } } else if (part.isMimeType("message/rfc822")) { saveAttachMent((Part) part.getContent(),filePath); } } /** * 保存附件到指定目录里 * @param fileName：附件名称 * @param in：文件输入流 * @param filePath：邮件附件存放基路径 */ private void saveFile(String fileName, InputStream in,String filePath) throws Exception { File storefile = new File(filePath); if(!storefile.exists()){ storefile.mkdirs(); } BufferedOutputStream bos = null; BufferedInputStream bis = null; try { bos = new BufferedOutputStream(new FileOutputStream(filePath + "\" + fileName)); bis = new BufferedInputStream(in); int c; while ((c = bis.read()) != -1) { bos.write(c); bos.flush(); } } catch (Exception e) { throw e; } finally { if(bos != null){ bos.close(); } if(bis != null){ bis.close(); } } } }?3、测试程序
package com.bao.main;import com.bao.receivemail.ReceiveMailHandler;public class Main {public static void main(String[] args) {try {new ReceiveMailHandler().receiveMail("username", "password");} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}}运行结果会在控制台打印出来，只读取了邮箱中最新的那一封邮件。如果有附件，附件会自动保存到项目中你设置的文件目录中。程序不上传了，大家自己看下吧！谢谢大家的支持^.^！
辛苦啦~~~