使用javaMail收邮件 支持附件下载

javaMail 发送 复杂 邮件 附件

使用javaMail收邮件主要有两种协议，一种是pop3，一种是imap。这两种协议都可以用来收邮件，但是在其中的处理上是有区别的。pop3是不支持判断邮件是否为已读的，也就是说你不能直接从收件箱里面取到未读邮件，这需要自己进行判断，然而imap就提供了这样的功能，使用imap时可以很轻松的判断该邮件是否为已读或未读或其他。

 

此外收件箱中的每一封邮件都对应着一个MessageNumber，所以可以通过一个MessageNumber拿到对应的那封邮件。如：Message message = folder.getMessage(messageNumber);

 

pop3和imap主要区别就是能否判断邮件状态的问题，其他的操作都差不多.

 

pop3收邮件和解析邮件：

package com.clxx.test;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
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.Session;
import javax.mail.Store;
import javax.mail.internet.MimeMultipart;

public class Email2 {

    public static void main(String args[]) throws MessagingException,
            IOException {
        Properties props = new Properties();
        props.setProperty("mail.store.protocol", "pop3");
        props.setProperty("mail.pop3.host", "pop3.sohu.com");
        Session session = Session.getDefaultInstance(props);
        Store store = session.getStore("pop3");
        store.connect("[email protected]", "password");
        Folder folder = store.getFolder("INBOX");
        folder.open(Folder.READ_WRITE);

        // 全部邮件数
        int messageCount = folder.getMessageCount();
        System.out.println(messageCount);
        Message[] messages = folder.getMessages();
        for (int i = 0; i < messages.length; i++) {
            Message message = messages[i];
            System.out.println(message.getSubject());
            // 删除邮件
            // message.setFlag(Flags.Flag.DELETED, true);
            // 标记为已读
            // message.setFlag(Flags.Flag.SEEN, true);

            //pop3没有判断邮件是否为已读的功能，要使用Imap才可以
            /*Flags flags = message.getFlags();
            if (flags.contains(Flags.Flag.SEEN))
                System.out.println("这是一封已读邮件");
            else {
                System.out.println("未读邮件");
                message.setFlag(Flags.Flag.SEEN, true);
            }*/
            System.out.println("发送时间：" + message.getSentDate());
            System.out.println("主题：" + message.getSubject());
            System.out.println("内容：" + message.getContent());
            //获取所有的Header，头信息
            Enumeration headers = message.getAllHeaders();
            System.out.println("----------------------allHeaders-----------------------------");
        /*  while (headers.hasMoreElements()) {
                Header header = (Header)headers.nextElement();
                System.out.println(header.getName()+" ======= "+header.getValue());
            }*/

            //解析邮件内容
            Object content = message.getContent();
            if (content instanceof MimeMultipart) {
                MimeMultipart multipart = (MimeMultipart) content;
                parseMultipart(multipart);
            }
            System.out
                    .println("========================================================");
            System.out
                    .println("========================================================");

        }

        folder.close(true);
        store.close();
    }

    /**
     * 对复杂邮件的解析
     * @param multipart
     * @throws MessagingException
     * @throws IOException
     */
    public static void parseMultipart(Multipart multipart) throws MessagingException, IOException {
        int count = multipart.getCount();
        System.out.println("couont =  "+count);
        for (int idx=0;idx<count;idx++) {
            BodyPart bodyPart = multipart.getBodyPart(idx);
            System.out.println(bodyPart.getContentType());
            if (bodyPart.isMimeType("text/plain")) {
                System.out.println("plain................."+bodyPart.getContent());
            } else if(bodyPart.isMimeType("text/html")) {
                System.out.println("html..................."+bodyPart.getContent());
            } else if(bodyPart.isMimeType("multipart/*")) {
                Multipart mpart = (Multipart)bodyPart.getContent();
                parseMultipart(mpart);

            } else if (bodyPart.isMimeType("application/octet-stream")) {
                String disposition = bodyPart.getDisposition();
                System.out.println(disposition);
                if (disposition.equalsIgnoreCase(BodyPart.ATTACHMENT)) {
                    String fileName = bodyPart.getFileName();
                    InputStream is = bodyPart.getInputStream();
                    copy(is, new FileOutputStream("D:\\"+fileName));
                }
            }
        }
    }

    /**
     * 文件拷贝，在用户进行附件下载的时候，可以把附件的InputStream传给用户进行下载
     * @param is
     * @param os
     * @throws IOException
     */
    public static void copy(InputStream is, OutputStream os) throws IOException {
        byte[] bytes = new byte[1024];
        int len = 0;
        while ((len=is.read(bytes)) != -1 ) {
            os.write(bytes, 0, len);
        }
        if (os != null)
            os.close();
        if (is != null)
            is.close();
    }


}

package com.clxx.test;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
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.Session;
import javax.mail.Store;
import javax.mail.internet.MimeMultipart;

public class Email2 {

	public static void main(String args[]) throws MessagingException,
			IOException {
		Properties props = new Properties();
		props.setProperty("mail.store.protocol", "pop3");
		props.setProperty("mail.pop3.host", "pop3.sohu.com");
		Session session = Session.getDefaultInstance(props);
		Store store = session.getStore("pop3");
		store.connect("[email protected]", "password");
		Folder folder = store.getFolder("INBOX");
		folder.open(Folder.READ_WRITE);

		// 全部邮件数
		int messageCount = folder.getMessageCount();
		System.out.println(messageCount);
		Message[] messages = folder.getMessages();
		for (int i = 0; i < messages.length; i++) {
			Message message = messages[i];
			System.out.println(message.getSubject());
			// 删除邮件
			// message.setFlag(Flags.Flag.DELETED, true);
			// 标记为已读
			// message.setFlag(Flags.Flag.SEEN, true);
			
			//pop3没有判断邮件是否为已读的功能，要使用Imap才可以
			/*Flags flags = message.getFlags();
			if (flags.contains(Flags.Flag.SEEN))
				System.out.println("这是一封已读邮件");
			else {
				System.out.println("未读邮件");
				message.setFlag(Flags.Flag.SEEN, true);
			}*/
			System.out.println("发送时间：" + message.getSentDate());
			System.out.println("主题：" + message.getSubject());
			System.out.println("内容：" + message.getContent());
			//获取所有的Header，头信息
			Enumeration headers = message.getAllHeaders();
			System.out.println("----------------------allHeaders-----------------------------");
		/*	while (headers.hasMoreElements()) {
				Header header = (Header)headers.nextElement();
				System.out.println(header.getName()+" ======= "+header.getValue());
			}*/
			
			//解析邮件内容
			Object content = message.getContent();
			if (content instanceof MimeMultipart) {
				MimeMultipart multipart = (MimeMultipart) content;
				parseMultipart(multipart);
			}
			System.out
					.println("========================================================");
			System.out
					.println("========================================================");

		}

		folder.close(true);
		store.close();
	}
	
	/**
	 * 对复杂邮件的解析
	 * @param multipart
	 * @throws MessagingException
	 * @throws IOException
	 */
	public static void parseMultipart(Multipart multipart) throws MessagingException, IOException {
		int count = multipart.getCount();
		System.out.println("couont =  "+count);
		for (int idx=0;idx<count;idx++) {
			BodyPart bodyPart = multipart.getBodyPart(idx);
			System.out.println(bodyPart.getContentType());
			if (bodyPart.isMimeType("text/plain")) {
				System.out.println("plain................."+bodyPart.getContent());
			} else if(bodyPart.isMimeType("text/html")) {
				System.out.println("html..................."+bodyPart.getContent());
			} else if(bodyPart.isMimeType("multipart/*")) {
				Multipart mpart = (Multipart)bodyPart.getContent();
				parseMultipart(mpart);
				
			} else if (bodyPart.isMimeType("application/octet-stream")) {
				String disposition = bodyPart.getDisposition();
				System.out.println(disposition);
				if (disposition.equalsIgnoreCase(BodyPart.ATTACHMENT)) {
					String fileName = bodyPart.getFileName();
					InputStream is = bodyPart.getInputStream();
					copy(is, new FileOutputStream("D:\\"+fileName));
				}
			}
		}
	}
	
	/**
	 * 文件拷贝，在用户进行附件下载的时候，可以把附件的InputStream传给用户进行下载
	 * @param is
	 * @param os
	 * @throws IOException
	 */
	public static void copy(InputStream is, OutputStream os) throws IOException {
		byte[] bytes = new byte[1024];
		int len = 0;
		while ((len=is.read(bytes)) != -1 ) {
			os.write(bytes, 0, len);
		}
		if (os != null)
			os.close();
		if (is != null)
			is.close();
	}
	

}

 

 

使用imap协议接收邮件：

package com.clxx.test;

import java.util.Properties;

import javax.mail.Flags;
import javax.mail.Folder;
import javax.mail.Message;
import javax.mail.Session;

import com.sun.mail.imap.IMAPFolder;
import com.sun.mail.imap.IMAPStore;

/**
 * 使用imap协议获取未读邮件数
 *
 * @author w
 *
 */
public class Email3 {

    public static void main(String[] args) throws Exception {
        String user = "[email protected]";// 邮箱的用户名
        String password = "password"; // 邮箱的密码

        Properties prop = System.getProperties();
        prop.put("mail.store.protocol", "imap");
        prop.put("mail.imap.host", "imap.sohu.com");

        Session session = Session.getInstance(prop);

        int total = 0;
        IMAPStore store = (IMAPStore) session.getStore("imap"); // 使用imap会话机制，连接服务器
        store.connect(user, password);
        IMAPFolder folder = (IMAPFolder) store.getFolder("INBOX"); // 收件箱
        folder.open(Folder.READ_WRITE);
        // 获取总邮件数
        total = folder.getMessageCount();
        System.out.println("-----------------共有邮件：" + total
                + " 封--------------");
        // 得到收件箱文件夹信息，获取邮件列表
        System.out.println("未读邮件数：" + folder.getUnreadMessageCount());
        Message[] messages = folder.getMessages();
        int messageNumber = 0;
        for (Message message : messages) {
            System.out.println("发送时间：" + message.getSentDate());
            System.out.println("主题：" + message.getSubject());
            System.out.println("内容：" + message.getContent());
            Flags flags = message.getFlags();
            if (flags.contains(Flags.Flag.SEEN))
                System.out.println("这是一封已读邮件");
            else {
                System.out.println("未读邮件");
            }
            System.out
                    .println("========================================================");
            System.out
                    .println("========================================================");
            //每封邮件都有一个MessageNumber，可以通过邮件的MessageNumber在收件箱里面取得该邮件
            messageNumber = message.getMessageNumber();
        }
        Message message = folder.getMessage(messageNumber);
        System.out.println(message.getContent()+message.getContentType());
        // 释放资源
        if (folder != null)
            folder.close(true);
        if (store != null)
            store.close();
    }

}