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：

Java代码








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("username@sohu.com", "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("username@sohu.com", "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：

Java代码








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 = "username@sohu.com";// 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();
}

}