使用javamail查看有附件的邮件

以下是使用 JavaMail API 查看有附件的邮件的示例代码：

import java.io.IOException;
import java.util.Properties;

import javax.mail.BodyPart;
import javax.mail.Folder;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.Session;
import javax.mail.Store;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMultipart;

public class MailAttachmentViewer {
    public static void main(String[] args) throws Exception {
        Properties properties = new Properties();
        properties.put("mail.store.protocol", "imaps");
        properties.put("mail.imaps.host", "imap.gmail.com");
        properties.put("mail.imaps.port", "993");
        properties.put("mail.imaps.starttls.enable", "true");

        Session emailSession = Session.getDefaultInstance(properties);

        Store store = emailSession.getStore("imaps");
        store.connect("your-email@gmail.com", "your-password");

        Folder emailFolder = store.getFolder("INBOX");
        emailFolder.open(Folder.READ_ONLY);

        Message[] messages = emailFolder.getMessages();
        for (int i = 0; i < messages.length; i++) {
            Message message = messages[i];
            System.out.println("Subject: " + message.getSubject());
            System.out.println("From: " + message.getFrom()[0]);

            Object content = message.getContent();
            if (content instanceof Multipart) {
                Multipart multipart = (Multipart) content;
                for (int j = 0; j < multipart.getCount(); j++) {
                    BodyPart bodyPart = multipart.getBodyPart(j);
                    if (bodyPart instanceof MimeBodyPart) {
                        MimeBodyPart mimeBodyPart = (MimeBodyPart) bodyPart;
                        if (mimeBodyPart.getDisposition() != null && mimeBodyPart.getDisposition().equalsIgnoreCase("attachment")) {
                            System.out.println("Attachment found: " + mimeBodyPart.getFileName());
                            // if you want to download the attachment, use the following code:
                            // mimeBodyPart.saveFile("/path/to/save/attachment/" + mimeBodyPart.getFileName());
                        } else {
                            System.out.println("Text: " + mimeBodyPart.getContent().toString());
                        }
                    }
                }
            } else {
                System.out.println("Text: " + content.toString());
            }
        }

        emailFolder.close(false);
        store.close();
    }
}

请注意，如果您想下载附件，您需要取消注释示例代码中的一行，将附件保存到您的本地计算机上。