安卓开发：如何使用企业邮箱而非Gmail实现后台发送邮件功能

1 实现逻辑说明 #

你现有两套方案中，Intent唤起系统邮件选择器的方案需要用户手动操作，BackgroundMail是Gmail专属适配工具类，没有自定义SMTP配置入口，无法直接复用。企业邮箱后台发送需要基于通用SMTP协议实现，使用Android适配版JavaMail库即可完成。

2 第一步：添加依赖 #

在app模块的build.gradle的dependencies代码块中添加如下依赖：

implementation 'com.sun.mail:android-mail:1.6.7'
implementation 'com.sun.mail:android-activation:1.6.7'

3 第二步：自定义企业邮件发送工具类 #

import android.os.AsyncTask;
import java.util.Properties;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
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.activation.DataHandler;
import javax.activation.FileDataSource;

public class EnterpriseMailSender extends AsyncTask<Void, Void, Boolean> {
    // 以下企业邮箱SMTP参数请先找你司邮箱管理员确认正确值
    private static final String SMTP_HOST = "smtp.wind.energy";
    private static final String SMTP_PORT = "465";
    private static final boolean USE_SSL = true;

    private final String senderEmail = "m.nebo@wind.energy";
    private final String senderPassword = "你的企业邮箱密码/授权码";
    private final String receiverEmail;
    private final String subject;
    private final String content;
    private final String attachmentPath; // 无附件传null即可

    public EnterpriseMailSender(String receiverEmail, String subject, String content, String attachmentPath) {
        this.receiverEmail = receiverEmail;
        this.subject = subject;
        this.content = content;
        this.attachmentPath = attachmentPath;
    }

    @Override
    protected Boolean doInBackground(Void... voids) {
        Properties props = new Properties();
        props.put("mail.smtp.host", SMTP_HOST);
        props.put("mail.smtp.port", SMTP_PORT);
        props.put("mail.smtp.auth", "true");
        if(USE_SSL){
            props.put("mail.smtp.socketFactory.port", SMTP_PORT);
            props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
            props.put("mail.smtp.socketFactory.fallback", "false");
        } else {
            props.put("mail.smtp.starttls.enable", "true");
        }

        Session session = Session.getInstance(props, new Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(senderEmail, senderPassword);
            }
        });

        try {
            MimeMessage message = new MimeMessage(session);
            message.setFrom(new InternetAddress(senderEmail));
            message.addRecipient(Message.RecipientType.TO, new InternetAddress(receiverEmail));
            message.setSubject(subject);

            // 组装正文和附件
            MimeMultipart multipart = new MimeMultipart();
            // 正文部分
            MimeBodyPart textPart = new MimeBodyPart();
            textPart.setText(content);
            multipart.addBodyPart(textPart);

            // 附件部分
            if(attachmentPath != null && !attachmentPath.isEmpty()){
                MimeBodyPart attachmentPart = new MimeBodyPart();
                FileDataSource source = new FileDataSource(attachmentPath);
                attachmentPart.setDataHandler(new DataHandler(source));
                attachmentPart.setFileName(source.getName());
                multipart.addBodyPart(attachmentPart);
            }

            message.setContent(multipart);
            Transport.send(message);
            return true;
        } catch (MessagingException e) {
            e.printStackTrace();
            return false;
        }
    }

    @Override
    protected void onPostExecute(Boolean success) {
        super.onPostExecute(success);
        // 此处可自定义发送结果回调逻辑，比如成功提示、失败重试
    }
}

4 第三步：调用示例 #

和你原来BackgroundMail的调用逻辑一致，直接在需要发邮件的地方调用即可：

// 带附件发送示例
String pdfPath = filePath.exists() ? Pdf_Path : null;
new EnterpriseMailSender(Commen.Email_Abrechnung, emailBetreff, emailText, pdfPath).execute();

注意事项 #

• 先在AndroidManifest.xml中添加必要权限：

<uses-permission android:name="android.permission.INTERNET" />
<!-- 读取附件需要的存储权限，根据你的targetSdk版本适配 -->
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_MEDIA_IMAGES" />

• 多数企业邮箱SMTP发信需要使用授权码而非账号登录密码，需要提前确认
• 不要把邮箱密码硬编码在客户端代码中，容易被反编译泄露，生产环境建议把发信逻辑放到后端服务，客户端仅调用后端发信接口
• 安卓10及以上版本需要适配分区存储规则，确保附件路径可被正常读取

内容的提问来源于stack exchange，提问作者Nebo Mohamed