java读取邮件

Posted 2020-06-09

package com.zz.mail;  
  
import java.io.FileNotFoundException;  
import java.io.FileOutputStream;  
import java.io.IOException;  
import java.io.InputStream;  
import java.io.UnsupportedEncodingException;  
import java.util.Properties;  
import javax.mail.Address;  
import javax.mail.Folder;  
import javax.mail.Message;  
import javax.mail.MessagingException;  
import javax.mail.Multipart;  
import javax.mail.NoSuchProviderException;  
import javax.mail.Part;  
import javax.mail.Session;  
import javax.mail.Store;  
import javax.mail.internet.InternetAddress;  
import javax.mail.internet.MimeUtility;  

/** 
* 邮件接受测试 
*  
*/ 
public class POP3MailReceiverTest {  
    public POP3MailReceiverTest() {  
        try {
            // 1. 设置连接信息, 生成一个 Session  
            String protocol = "pop3";
            boolean isSSL = true;
            String host = "pop.163.com";
            int port = 995;
            String username = "[email protected]";
            String password = "****";
     
            Properties props = new Properties();
            props.put("mail.pop3.ssl.enable", isSSL);
            props.put("mail.pop3.host", host);
            props.put("mail.pop3.port", port);
     
            Session session = Session.getDefaultInstance(props);
            // 2. 获取 Store 并连接到服务器    
            Store store = session.getStore(protocol);
            store.connect(username, password);
            Folder folder = store.getDefaultFolder();// 默认父目录  
            if (folder == null) {  
                System.out.println("服务器不可用");  
                return;  
            }  
          /* 
           System.out.println("默认信箱名:" + folder.getName()); 
 
           Folder[] folders = folder.list();// 默认目录列表 
           for(int i = 0; i < folders.length; i++) { 
               System.out.println(folders[0].getName()); 
           } 
            System.out.println("默认目录下的子目录数: " + folders.length); 
            */  
            Folder popFolder = folder.getFolder("INBOX");// 获取收件箱  
            popFolder.open(Folder.READ_WRITE);// 可读邮件,可以删邮件的模式打开目录  
            // 4. 列出来收件箱 下所有邮件  
            Message[] messages = popFolder.getMessages();  
            // 取出来邮件数  
            int msgCount = popFolder.getMessageCount();  
            System.out.println("共有邮件: " + msgCount + "封");  
            // FetchProfile fProfile = new FetchProfile();// 选择邮件的下载模式,  
            // 根据网速选择不同的模式  
            // fProfile.add(FetchProfile.Item.ENVELOPE);  
            // folder.fetch(messages, fProfile);// 选择性的下载邮件  
            // 5. 循环处理每个邮件并实现邮件转为新闻的功能  
            for (int i = 0; i < msgCount; i++) {  
                // 单个邮件  
                System.out.println("第" + i +"邮件开始");  
                mailReceiver(messages[i]);  
                System.out.println("第" + i +"邮件结束");  
               //邮件读取用来校验  
                 messages[i].writeTo(new FileOutputStream("D:/pop3MailReceiver"+ i +".eml"));  
            }    
            // 7. 关闭 Folder 会真正删除邮件, false 不删除  
            popFolder.close(true);  
            // 8. 关闭 store, 断开网络连接  
            store.close();  
        } catch (NoSuchProviderException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        } catch (Exception e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
    }  
      
    /** 
     * 解析邮件 
     *  
     * @param messages 邮件对象 
     * @param i 
     * @return 
     * @throws IOException 
     * @throws MessagingException 
     * @throws FileNotFoundException 
     * @throws UnsupportedEncodingException 
     */  
    private void mailReceiver(Message msg)throws Exception{  
        // 发件人信息  
        Address[] froms = msg.getFrom();  
        if(froms != null) {  
            //System.out.println("发件人信息:" + froms[0]);  
            InternetAddress addr = (InternetAddress)froms[0];  
            System.out.println("发件人地址:" + addr.getAddress());  
            System.out.println("发件人显示名:" + addr.getPersonal());  
        }  
        System.out.println("邮件主题:" + msg.getSubject());  
        // getContent() 是获取包裹内容, Part相当于外包装  
        Object o = msg.getContent();  
        if(o instanceof Multipart) {  
            Multipart multipart = (Multipart) o ;  
            reMultipart(multipart);  
        } else if (o instanceof Part){  
            Part part = (Part) o;   
            rePart(part);  
        } else {  
            System.out.println("类型" + msg.getContentType());  
            System.out.println("内容" + msg.getContent());  
        }  
    }  
      
    /** 
     * @param part 解析内容 
     * @throws Exception 
     */  
    private void rePart(Part part) throws MessagingException,  
            UnsupportedEncodingException, IOException, FileNotFoundException {  
        if (part.getDisposition() != null) {  
          
            String strFileNmae = MimeUtility.decodeText(part.getFileName()); //MimeUtility.decodeText解决附件名乱码问题  
            System.out.println("发现附件: " +  MimeUtility.decodeText(part.getFileName()));  
            System.out.println("内容类型: " + MimeUtility.decodeText(part.getContentType()));  
            System.out.println("附件内容:" + part.getContent());  
            InputStream in = part.getInputStream();// 打开附件的输入流  
            // 读取附件字节并存储到文件中  
            java.io.FileOutputStream out = new FileOutputStream(strFileNmae);  
            int data;  
            while((data = in.read()) != -1) {  
                out.write(data);  
            }  
            in.close();  
            out.close();  
        } else {  
            if(part.getContentType().startsWith("text/plain")) {  
                System.out.println("文本内容：" + part.getContent());  
            } else {  
                //System.out.println("html内容：" + part.getContent());  
            }  
        }  
    }  
      
    /** 
     * @param multipart // 接卸包裹（含所有邮件内容(包裹+正文+附件)） 
     * @throws Exception 
     */  
    private void reMultipart(Multipart multipart) throws Exception {  
        //System.out.println("邮件共有" + multipart.getCount() + "部分组成");  
        // 依次处理各个部分  
        for (int j = 0, n = multipart.getCount(); j < n; j++) {  
            //System.out.println("处理第" + j + "部分");  
            Part part = multipart.getBodyPart(j);//解包, 取出 MultiPart的各个部分, 每部分可能是邮件内容,  
            // 也可能是另一个小包裹(MultipPart)  
            // 判断此包裹内容是不是一个小包裹, 一般这一部分是 正文 Content-Type: multipart/alternative  
            if (part.getContent() instanceof Multipart) {  
                Multipart p = (Multipart) part.getContent();// 转成小包裹  
                //递归迭代  
                reMultipart(p);  
            } else {  
                rePart(part);  
            }  
         }  
    }  
      
    /** 
     * @param args 
     */  
    public static void main(String[] args) {  
        new POP3MailReceiverTest();  
    }  
}