从gmail阅读电子邮件无效

Question

我正在使用Java Mail API以及以下代码来阅读我的Gmail帐户中的电子邮件.

import java.util.Properties;
import javax.mail.Folder;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.NoSuchProviderException;
import javax.mail.Session;
import javax.mail.Store;

public class CheckMails {

   public static void check(String host, String storeType, String user,
      String password) 
   {
      try {
      Properties properties = new Properties();

      properties.put("mail.pop3.host", host);
      properties.put("mail.pop3.port", "995");
      properties.put("mail.pop3.starttls.enable", "true");
      Session emailSession = Session.getDefaultInstance(properties);

      //create the POP3 store object and connect with the pop server
      Store store = emailSession.getStore("pop3s");

      store.connect(host, user, password);

      //create the folder object and open it
      Folder emailFolder = store.getFolder("INBOX");
      emailFolder.open(Folder.READ_ONLY);

      // retrieve the messages from the folder in an array and print it
      Message[] messages = emailFolder.getMessages();
      System.out.println("messages.length---" + messages.length);

      for (int i = 0, n = messages.length; i < n; i++) {
         Message message = messages[i];
         System.out.println("---------------------------------");
         System.out.println("Email Number " + (i + 1));
         System.out.println("Subject: " + message.getSubject());
         System.out.println("From: " + message.getFrom()[0]);
         System.out.println("Text: " + message.getContent().toString());

      }

      //close the store and folder objects
      emailFolder.close(false);
      store.close();

      } catch (NoSuchProviderException e) {
         e.printStackTrace();
      } catch (MessagingException e) {
         e.printStackTrace();
      } catch (Exception e) {
         e.printStackTrace();
      }
   }
   public static void main(String[] args) {
      String host = "pop.gmail.com";// change accordingly
      String mailStoreType = "pop3";
      String username = "myemai@gmail.com";// change accordingly
      String password = "*******";// change accordingly

      check(host, mailStoreType, username, password);

   }

}

但我得到以下例外情况:

javax.mail.AuthenticationFailedException: [AUTH] Web login required: `    https://support.google.com/mail/bin/answer.py?answer=78754`
at com.sun.mail.pop3.POP3Store.protocolConnect(POP3Store.java:209)
at javax.mail.Service.connect(Service.java:364)
at javax.mail.Service.connect(Service.java:245)
at CheckMails.check(CheckMails.java:26)
at CheckMails.main(CheckMails.java:66)

但我收到了一封来自我的收件箱中的gmail的电子邮件,其中说"我们最近封锁了一个尝试使用您的Google帐户的登录信息".如何让程序正常工作？

Answer 1

用.改变你的emailSession变量

Session emailSession = Session.getInstance(props, new javax.mail.Authenticator() {
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication(userName, password);
    }
});

正如Gmail所说

某些应用和设备使用安全性较低的登录技术,这会使您的帐户更容易受到攻击.您可以关闭我们建议的这些应用的访问权限,或者如果您想要使用它们,请尽快启用访问权限.学到更多

只需点击下面的链接并停用Gmail安全设置即可.

禁用安全设置

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