(Java) 发送邮件工具类

依赖文件

<!-- https://mvnrepository.com/artifact/com.sun.mail/javax.mail -->
<dependency>
    <groupId>com.sun.mail</groupId>
    <artifactId>javax.mail</artifactId>
    <version>1.6.2</version>
</dependency>

package com.newpay.common;

import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.*;
import javax.mail.internet.*;
import java.io.UnsupportedEncodingException;
import java.util.Date;
import java.util.Properties;

public class EmailUtils {

    //发送的邮箱 内部代码只适用qq邮箱
    private static final String USER = "xxxx@qq.com";
    //授权密码 通过QQ邮箱设置->账户->POP3/IMAP/SMTP/Exchange/CardDAV/CalDAV服务->开启POP3/SMTP服务获取
    private static final String PWD = "";

    private String[] to;
    private String[] cc;//抄送
    private String[] bcc;//密送
    private String[] fileList;//附件
    private String subject;//主题
    private String content;//内容，可以用html语言写


    //后加的防止题目过长或附件名称有中文进行全局定义
    static {
        System.setProperty("mail.mime.splitlongparameters","false");
        System.setProperty("mail.mime.charset","UTF-8");
    }

    public void sendMessage() throws MessagingException, UnsupportedEncodingException {
        // 配置发送邮件的环境属性
        final Properties props = new Properties();
        //下面两段代码是设置ssl和端口，不设置发送不出去。
        props.setProperty("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
        //props.setProperty("mail.smtp.port", "465");
        props.setProperty("mail.smtp.socketFactory.port", "465");
        // 表示SMTP发送邮件，需要进行身份验证
        // 设置传输协议
        props.setProperty("mail.transport.protocol", "smtp");
        props.put("mail.smtp.auth", "true");
        //QQ邮箱的服务器 如果是企业邮箱或者其他邮箱得更换该服务器地址
        props.put("mail.smtp.host", "smtp.qq.com");
        // 发件人的账号
        props.put("mail.user", USER);
        // 访问SMTP服务时需要提供的密码
        props.put("mail.password", PWD);

        // 构建授权信息，用于进行SMTP进行身份验证
        Authenticator authenticator = new Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                // 用户名、密码
                String userName = props.getProperty("mail.user");
                String password = props.getProperty("mail.password");
                return new PasswordAuthentication(userName, password);
            }
        };
        // 使用环境属性和授权信息，创建邮件会话
        Session mailSession = Session.getInstance(props, authenticator);
        // 创建邮件消息
        MimeMessage message = new MimeMessage(mailSession);
        BodyPart messageBodyPart = new MimeBodyPart();
        Multipart multipart = new MimeMultipart();
        // 设置发件人
        InternetAddress form = new InternetAddress(
                props.getProperty("mail.user"));
        message.setFrom(form);
        //发送
        if (to != null) {
            String toList = getMailList(to);
            InternetAddress[] iaToList = new InternetAddress().parse(toList);
            message.setRecipients(Message.RecipientType.TO, iaToList); // 收件人
        }
        //抄送
        if (cc != null) {
            String toListcc = getMailList(cc);
            InternetAddress[] iaToListcc = new InternetAddress().parse(toListcc);
            message.setRecipients(Message.RecipientType.CC, iaToListcc); // 抄送人
        }
        //密送
        if (bcc != null) {
            String toListbcc = getMailList(bcc);
            InternetAddress[] iaToListbcc = new InternetAddress().parse(toListbcc);
            message.setRecipients(Message.RecipientType.BCC, iaToListbcc); // 密送人
        }
        message.setSentDate(new Date()); // 发送日期 该日期可以随意写,你可以写上昨天的日期（效果很特别,亲测,有兴趣可以试试）,或者抽象出来形成一个参数。
        message.setSubject(subject); // 主题
        message.setText(content); // 内容
        //显示以html格式的文本内容
        messageBodyPart.setContent(content,"text/html;charset=utf-8");
        multipart.addBodyPart(messageBodyPart);
        //保存多个附件
        if(fileList!=null){
            addTach(fileList, multipart);
        }
        message.setContent(multipart);
        // 发送邮件
        Transport.send(message);
    }

    public void setTo(String[] to) {
        this.to = to;
    }

    public void setCc(String[] cc) {
        this.cc = cc;
    }

    public void setBcc(String[] bcc) {
        this.bcc = bcc;
    }

    public void setSubject(String subject) {
        this.subject = subject;
    }

    public void setContent(String content) {
        this.content = content;
    }

    public void setFileList(String[] fileList) {
        this.fileList = fileList;
    }

    private String getMailList(String[] mailArray) {
        StringBuffer toList = new StringBuffer();
        int length = mailArray.length;
        if (mailArray != null && length < 2) {
            toList.append(mailArray[0]);
        } else {
            for (int i = 0; i < length; i++) {
                toList.append(mailArray[i]);
                if (i != (length - 1)) {
                    toList.append(",");
                }
            }
        }
        return toList.toString();
    }

    //添加多个附件
    public void addTach(String fileList[], Multipart multipart) throws MessagingException, UnsupportedEncodingException {
        for (int index = 0; index < fileList.length; index++) {
            MimeBodyPart mailArchieve = new MimeBodyPart();
            FileDataSource fds = new FileDataSource(fileList[index]);
            mailArchieve.setDataHandler(new DataHandler(fds));
            mailArchieve.setFileName(MimeUtility.encodeText(fds.getName(),"UTF-8","B"));
            multipart.addBodyPart(mailArchieve);
        }
    }

}