带有gui的javamail多附件

Question

尝试用GUI做一个基本的邮件发送者应用程序，但无论我做什么都无法发送/添加多个附件(尝试了旧Stack Overflow问题中的大多数答案-不起作用，
我不想手动添加"multipart.addBodyPart(messageBodyPart("每个附件。有没有一种方法可以添加多个附件而不重复代码(。我错过了什么，出了什么问题？(作为附件添加的完整GUI照片和红色单词是变量名称
link=[1]：https://i.stack.imgur.com/KVVc9.png(

try 
{
Message message = new MimeMessage(session);
message.setFrom(new InternetAddress(FromMail));
message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(ToMail));
message.setSubject(SubjectMail);
//message.setText(ContentMail);

MimeBodyPart messageBodyPart = new MimeBodyPart();
messageBodyPart.setText(ContentMail);

Multipart multipart = new MimeMultipart();
multipart.addBodyPart(messageBodyPart);

messageBodyPart = new MimeBodyPart();

DataSource source = new FileDataSource(AttachmentPath);

messageBodyPart.setDataHandler(new DataHandler(source));
messageBodyPart.setFileName(attachment_name.getText());

multipart.addBodyPart(messageBodyPart);

message.setContent(multipart);

Transport.send(message);

JOptionPane.showMessageDialog(null, "success, message sent!");
} 
catch (Exception exp) 
{
JOptionPane.showMessageDialog(null, exp);
}
}
private void attachmentActionPerformed(java.awt.event.ActionEvent evt) {                                           
// TODO add your handling code here:

JFileChooser chooser = new JFileChooser();
chooser.setMultiSelectionEnabled(true);

Component frame = null;
chooser.showOpenDialog(frame);

File file = chooser.getSelectedFile();
AttachmentPath = file.getAbsolutePath();

//path_attachment.setText(AttachmentPath);
path_attachment_area.setText(AttachmentPath);
} 
String AttachmentPath;

Answer 1

这是一个最小的GUI，有两个按钮，Attach和Send，还有一个用于收集选定文件的文本区域，我没有复制您的完整GUI，所以您必须将其集成到代码中。

实际上，您只需要选中选择附件的onAttach()和将所有选定附件添加到消息中的onSend()。

请注意，文本区域仅用于显示所选文件，但文件列表保留在ArrayList中。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.Multipart;
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.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class TestEmail extends JPanel {
String fromEmail = "[e-mail]";
String toEmail = "[e-mail]";
protected JButton attachButton=new JButton("Add attachment(s)");
protected JButton sendButton=new JButton("Send");
protected JTextArea attachmentsArea=new JTextArea(10, 30);
protected JFileChooser chooser=new JFileChooser();

protected List<File> attachments=new ArrayList<File>();
public TestEmail() {
setLayout(new BorderLayout());
attachmentsArea.setEditable(false);
chooser.setMultiSelectionEnabled(true);
JScrollPane scrollPane=new JScrollPane(attachmentsArea);
add(scrollPane,BorderLayout.CENTER);

Box buttonPanel=new Box(BoxLayout.X_AXIS);
buttonPanel.add(Box.createHorizontalGlue());
buttonPanel.add(attachButton);
buttonPanel.add(sendButton);

add(buttonPanel,BorderLayout.SOUTH);
attachButton.addActionListener((e)->onAttach());
sendButton.addActionListener((e)->onSend());
}
public Session getSession() {
final String password = "mypassword";
Properties props = new Properties();
props.put("mail.smtp.host", "smtp.mydomain.com"); // SMTP Host
props.put("mail.smtp.port", "465");
props.put("mail.smtp.auth", "true"); // enable authentication
props.put("mail.smtp.socketFactory.class",
"javax.net.ssl.SSLSocketFactory");  
Authenticator auth = new Authenticator() {
// override the getPasswordAuthentication method
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(fromEmail, password);
}
};
return Session.getInstance(props, auth);
}
public void onAttach() {
if (chooser.showOpenDialog(this)==JFileChooser.APPROVE_OPTION) {
for (File f: chooser.getSelectedFiles()) {
if (!f.isDirectory()&&!attachments.contains(f)) {
attachments.add(f);
attachmentsArea.append(f.getAbsolutePath()+"n");
}
}
}
}

public void onSend() {
try {
Session session = getSession();
Message message = new MimeMessage(session);
message.setFrom(new InternetAddress(fromEmail));
message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toEmail));
message.setSubject("A subject");

MimeBodyPart messageBodyPart = new MimeBodyPart();
messageBodyPart.setText("Dummy message, just to send attachments.");

Multipart multipart = new MimeMultipart();
multipart.addBodyPart(messageBodyPart);

for (File f: attachments) {
MimeBodyPart part=new MimeBodyPart();
part.attachFile(f);
multipart.addBodyPart(part);
}
message.setContent(multipart);
Transport.send(message);
JOptionPane.showMessageDialog(this, "Message successfully sent", "Success", JOptionPane.INFORMATION_MESSAGE);
} catch (Exception ex) {
ex.printStackTrace();
JOptionPane.showMessageDialog(this, "Exception sending e-mail:n"+ex.getMessage(),"Error", JOptionPane.ERROR_MESSAGE);
}
}

public static void main(String[] args) {
EventQueue.invokeLater(()->{
JFrame frame=new JFrame("Sendmail");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(new TestEmail());
frame.pack();
frame.setVisible(true);
});
}
}