计算 Gmail 收件箱中的电子邮件数量

This is the code that counts the number of mails in the gmail inbox.

Properties props = new Properties();
    props.put("mail.pop3.host" , "pop.gmail.com");
    props.put("mail.pop3.user" , "username");
    props.put("mail.pop3.socketFactory" , 995 );
    props.put("mail.pop3.socketFactory.class" , "javax.net.ssl.SSLSocketFactory" );
    props.put("mail.pop3.port" , 995);
    Session session = Session.getDefaultInstance(props , new Authenticator() {
        @Override
                protected PasswordAuthentication getPasswordAuthentication() {
                    return new PasswordAuthentication( "username" , "password");
                }
    });
    try {
        Store store  = session.getStore("pop3");
        store.connect("pop.gmail.com" , "username" , "password");
        Folder fldr = store.getFolder("INBOX");
        fldr.open(Folder.HOLDS_MESSAGES);
        int count = fldr.getMessageCount();
        System.out.println(count);
    } catch(Exception exc) {
        System.out.println(exc + " error");
    }

我得到的计数等于 7，但我应该得到 3，因为我的收件箱中只有 3 条消息.