design sketch

Code

package com.mabo.email;

import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;
import javax.mail.*;
import javax.mail.internet.*;
import java.io.File;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
/** * @Author mabo * @Description smtp service  *  Send E-mail  *  The email address of the sender is : NetEase mail box 、QQ mailbox 、139 mailbox  *  Unlimited receiving mailbox  *  Recommended QQ Of smtp The server , Faster  *  It is not recommended to use 139 mailbox  * 139 mailbox , Unable to send mail without attachments  */

public class EmailTest{
    
    //QQsmtp The server 
    private static final String QQHost="smtp.qq.com";
    private static final String QQPort="587";
    // NetEase smtp The server 
    private static final String WangYiHost="smtp.163.com";
    private static final String WangYiPort="25";
    //139 mailbox , Cannot send without attachments 
    private static final String E139Host="smtp.139.com";
    private static final String E139Port="25";

    public static void main(String[] args) throws Exception {
    
        // The sender's email is qq mailbox 
        String username="[email protected]";
        // To configure QQsmtp The token after the server succeeds 
        String password="xxxsfqvondjee";
        // Email address 1
        String receive1="[email protected]";
        // Email address 2
        String receive2="[email protected]";

// // The sender is Netease email 
// String username = "[email protected]";
// // Configure Netease smtp The token after the server succeeds 
// String password = "xxxHWSRPNFHI";
// //  Email address 1
// String receive1="[email protected]";

// // The sender is 139 mailbox 
// String username = "[email protected]";
// // Configure Netease smtp The token after the server succeeds 
// String password = "xxx63ce95564ce00";
// // Email address 1
// String receive1="[email protected]";


        // Attachments sent 
        List<String> list=new ArrayList<>();
        list.add("F:/test.doc");
        list.add("F:/testw copy .doc");

        // Mail recipient collection 
        List<String> listReceiver=new ArrayList<>();
        
        listReceiver.add(receive1);
        listReceiver.add(receive2);

        // Send mail without attachments 
        sendEmailNoFile(username,password,receive1," title , No attachment "," Text , No attachment ");

        // Send with attachment , Messages with multiple recipients and attachments 
        sendEmail(username,password,listReceiver," title , With accessories "," Text , With accessories ",list);

        System.out.println(" Send successfully ");
    }

    /** * @Author mabo * @Description  E-mail , Include attachments  * String sender, Sender email  * String password , Mailbox token  * List<String> receives, Recipient mailbox collection  * String subject, title  * String content, Text  * List<String> files File name , by null Do not send attachments  */
    public static void sendEmail(String sender,String password ,List<String> receivers,String subject, String content,List<String> files) throws Exception {
    
        String host;
        String port;
        if (sender.contains("@163.com")){
    
            host =WangYiHost;
            port =WangYiPort;
        }
        else if (sender.contains("@qq.com")){
    
            host =QQHost;
            port =QQPort;
        }
        else if (sender.contains("@139.com")){
    
            host =E139Host;
            port =E139Port;
        }
        else {
    
            throw  new Exception(" The current sender email does not support smtp The server ");
        }
        //  establish Properties  Class is used to record some properties of the mailbox 
        Properties props = new Properties();
        //  Express SMTP Send E-mail , Authentication is required 
        props.put("mail.smtp.auth", "true");
        // Fill in here SMTP The server 
        props.put("mail.smtp.host", host);
        // Port number ,QQ Mailbox port 587
        props.put("mail.smtp.port", port);
        //  Fill in here , The account number of the writer 
        props.put("mail.user", sender);
        //  Fill in here 16 position STMP password 
        props.put("mail.password", password);

        //  Build authorization information , Used for SMTP Authentication 
        Authenticator authenticator = new Authenticator() {
    

            protected PasswordAuthentication getPasswordAuthentication() {
    
                //  user name 、 password 
                String userName = props.getProperty("mail.user");
                String password = props.getProperty("mail.password");
                return new PasswordAuthentication(userName, password);
            }
        };
        //  Use environment properties and authorization information , Create a mail session 
        Session session = Session.getInstance(props, authenticator);
        session.setDebug(true);
        try {
    
            List<File> attaches = new ArrayList<File>();
            if (files!=null){
    
                for (String file: files) {
    
                    File attach = new File(file);
                    attaches.add(attach);
                }
            }
            // according to session establish MimeMessage
            MimeMessage message = new MimeMessage(session);
            // Sender 
            message.setFrom(new InternetAddress(sender));
            // The recipient 
            for (String receive:
                    receivers) {
    
                message.addRecipient(Message.RecipientType.TO, new InternetAddress(receive));
            }


            // The theme 
            message.setSubject(subject);

            Multipart multipart = new MimeMultipart();
            // Message body 
            BodyPart contentPart = new MimeBodyPart();
            contentPart.setContent(content, "text/html;charset=utf-8");
            multipart.addBodyPart(contentPart);
            // Email attachment 
            if(attaches.size()>0) {
    
                for(File attachment : attaches) {
    
                    BodyPart attachmentPart = new MimeBodyPart();
                    DataSource source = new FileDataSource(attachment);
                    attachmentPart.setDataHandler(new DataHandler(source));
                    // Avoid the processing of Chinese garbled code 
                    attachmentPart.setFileName(MimeUtility.encodeWord(attachment.getName()));
                    multipart.addBodyPart(attachmentPart);
                }
            }
            message.setContent(multipart);
            // Save message 
            message.saveChanges();
            Transport.send(message);
        } catch (AddressException e) {
    
            throw new AddressException(" Receiving mailbox not found ");
        } catch (MessagingException e) {
    
            throw new MessagingException(" fail in send ");
        } catch (UnsupportedEncodingException e) {
    
            throw new UnsupportedEncodingException(" fail in send ");
        }


    }

    /** * @Author mabo * @Description  Send mail one-to-one , Do not include attachments  * String sender, Sender email  * String password , Mailbox token  * String receives, Recipient email  * String subject, title  * String content, Text  */
    public static void sendEmailNoFile(String sender,String password ,String receiver,String subject, String content) throws Exception {
    
        ArrayList<String> objects = new ArrayList<>();
        objects.add(receiver);
        sendEmail(sender,password,objects,subject,content,null);
    }

}

How to open QQ mailbox SMTP service

NetEase and QQ Opening of mailbox SMTP The service settings are similar

1. Enter the mailbox , Click Settings
   
2. Click to enter the account or account security
   
3. Glide down to find SMTP service , Click to open , The installation prompt step sending SMS is enabled
   
   

4. SMS verification succeeded , Get password , That is... In the code password, Then you can start using it in your code

How to open Netease mailbox SMTP service

1. Enter the home page , Click Settings , Click on POP3/SMTP/IMAP
   

2. Click to open smtp service
   

3. According to the prompt , Send SMS verification code , Finally get the token , You can use smtp service