邮件 API : Username and Password not accepted (Gmail)

Question

我想从我的 java 应用程序发送电子邮件到 gmail 帐户我使用了以下代码和 javaMail API，但是 Gmail 不接受用户名和密码并抛出异常 谁能帮我解决这个问题？

邮件服务.java

public class MailService {

    String email;
    String content;
    public void sendMail(String email,String content)
    {
        this.email=email;
        this.content=content;
        // Recipient's email ID needs to be mentioned.
          String to = email;

          // Sender's email ID needs to be mentioned
          String from = senderemail@gmail.com;
          final String username = "myusername";//change accordingly
          final String password = "*******";//change accordingly

          // Assuming you are sending email through relay.jangosmtp.net
          String host = "smtp.gmail.com";

          Properties props = new Properties();
          props.put("mail.smtp.auth", "true");
          props.put("mail.smtp.starttls.enable", "true");
          props.put("mail.smtp.host", host);
          props.put("mail.smtp.port", "587");

          // Get the Session object.
          Session session = Session.getInstance(props,
             new javax.mail.Authenticator() {
                protected PasswordAuthentication getPasswordAuthentication() {
                   return new PasswordAuthentication(username, password);
           }
             });

          try {
           // Create a default MimeMessage object.
           Message message = new MimeMessage(session);

           // Set From: header field of the header.
           message.setFrom(new InternetAddress(from));

           // Set To: header field of the header.
           message.setRecipients(Message.RecipientType.TO,
                   InternetAddress.parse(to));

           // Set Subject: header field
           message.setSubject("Did you get my message?");

           // Now set the actual message
           message.setText(content);

           // Send message
           Transport.send(message);

           System.out.println("Sent message successfully....");

          } catch (MessagingException e) {
             throw new RuntimeException(e);
          }
       }
    }

Answer 1

为了能够通过您的 gmail 帐户发送邮件消息，您应该在 Google 帐户安全设置中允许不安全的应用程序(从 gmail 的角度来看，您的应用程序是这样的)。

更新: 此外，如果您想查看调试消息，请使用下一个 java 邮件属性:

props.put("mail.debug", "true");

它可以帮助您了解幕后发生的事情。