Java发送邮件，带抄送和附件的代码详解编程语言

import java.io.UnsupportedEncodingException; 
import java.util.Properties; 
  
import javax.activation.DataHandler; 
import javax.activation.FileDataSource; 
import javax.mail.BodyPart; 
import javax.mail.Message; 
import javax.mail.MessagingException; 
import javax.mail.Multipart; 
import javax.mail.Session; 
import javax.mail.Transport; 
import javax.mail.internet.InternetAddress; 
import javax.mail.internet.MimeBodyPart; 
import javax.mail.internet.MimeMessage; 
import javax.mail.internet.MimeMultipart; 
import javax.mail.internet.MimeUtility; 
  
  
public class EmailManager {  
  
    private Properties props; //系统属性  
    private Session session; //邮件会话对象  
    private MimeMessage mimeMsg; //MIME邮件对象  
    private Multipart mp; //Multipart对象,邮件内容,标题,附件等内容均添加到其中后再生成MimeMessage对象  
       
    /** 
     * Constructor 
     * @param smtp 邮件发送服务器 
     */ 
    public EmailManager(){ 
        props = System.getProperties();   
        props.put("mail.smtp.auth","false");  
        session = Session.getDefaultInstance(props, null); 
        session.setDebug(true); 
        mimeMsg = new MimeMessage(session); 
        mp = new MimeMultipart();  
    }  
  
    /** 
     * Constructor 
     * @param smtp 邮件发送服务器 
     */ 
    public EmailManager(String smtp, String username, String password){  
        props = System.getProperties(); 
        props.put("mail.smtp.auth","true");  
        props.put("mail.smtp.host", smtp); 
        props.put("username", username); 
        props.put("password", password); 
        session = Session.getDefaultInstance(props, null); 
        session.setDebug(true); 
        mimeMsg = new MimeMessage(session); 
        mp = new MimeMultipart();  
    }  
  
    /**  
     * 发送邮件 
     */  
    public boolean sendMail(String from, String[] to, String[] copyto, String subject, String content, String filename) { 
        try { 
            //设置发信人 
            mimeMsg.setFrom(new InternetAddress(from));  
            //设置接收人 
            for (int i = 0; i < to.length; i++) { 
                mimeMsg.setRecipients(Message.RecipientType.TO, InternetAddress.parse(to[i]));  
            } 
            //设置抄送人 
            for (int i = 0; i < copyto.length; i++) { 
                mimeMsg.setRecipients(Message.RecipientType.CC, InternetAddress.parse(copyto[i]));  
            } 
            //设置主题 
            mimeMsg.setSubject(subject); 
            //设置正文 
            BodyPart bp = new MimeBodyPart();  
            bp.setContent(content, "text/html;charset=utf-8"); 
            mp.addBodyPart(bp); 
            //设置附件 
            bp = new MimeBodyPart(); 
            FileDataSource fileds = new FileDataSource(filename);  
            bp.setDataHandler(new DataHandler(fileds));  
            bp.setFileName(MimeUtility.encodeText(fileds.getName(),"UTF-8","B")); 
            mp.addBodyPart(bp);  
            mimeMsg.setContent(mp);  
            mimeMsg.saveChanges();  
            //发送邮件 
            if(props.get("mail.smtp.auth").equals("true")){ 
                Transport transport = session.getTransport("smtp");  
                transport.connect((String)props.get("mail.smtp.host"), (String)props.get("username"), (String)props.get("password"));  
                transport.sendMessage(mimeMsg, mimeMsg.getRecipients(Message.RecipientType.TO));  
                transport.sendMessage(mimeMsg, mimeMsg.getRecipients(Message.RecipientType.CC));  
                transport.close();  
            }else{ 
                Transport.send(mimeMsg); 
            } 
            System.out.println("邮件发送成功"); 
        } catch (MessagingException e) { 
            // TODO Auto-generated catch block 
            e.printStackTrace(); 
        } catch (UnsupportedEncodingException e) { 
            // TODO Auto-generated catch block 
            e.printStackTrace(); 
        } 
        return true; 
    } 
      
    public static void main(String[] args){ 
        String smtp = "smtp.163.com"; 
        String username="[email protected]"; 
        String password="xxx"; 
        String from = "[email protected]"; 
        String[] to = {"[email protected]"}; 
        String[] copyto = {"[email protected]"}; 
        String subject = "主题"; 
        String content = "邮件内容"; 
       String filename = "D://xxx.txt"; 
       EmailManager email = new EmailManager(smtp, username, password); 
       email.sendMail(from, to, copyto, subject, content, filename); 
    } 
      
}