Javamail未讀消息返回最後一條消息而不是未讀

Question

這是我的代碼，它應該會得到未讀消息。不過，它正在返回收件箱中的最後一條消息。有什麼建議麼？

import javax.mail.*; 
import javax.mail.internet.*; 
import javax.mail.search.*; 
import java.util.*; 
import com.sun.mail.pop3.POP3SSLStore; 

public class MailClient { 
public static void main(String[] args) { 
    try { 
     Properties props = new Properties(); 
     props.setProperty("mail.pop3.connectionpooltimeout", "3000"); 
     props.setProperty("mail.pop3.connectiontimeout", "3000"); 
     props.setProperty("mail.pop3.timeout", "3000"); 

     Session session; 

      URLName url = new URLName("pop3","pop.gmail.com",995,"","email@gmail.com","pwd"); 
    session = Session.getInstance(props, null); 
    Store store = new POP3SSLStore(session,url); 
    store.connect(); 

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

    Flags seen = new Flags(Flags.Flag.SEEN); 
    FlagTerm unseenFlagTerm = new FlagTerm(seen,false); 
    Message message[] = folder.search(unseenFlagTerm); 

    for (int i=0, n = message.length;i<20;i++) { 
     System.out.println("Message " + (i + 1)); 
        System.out.println("From : " + message[i].getFrom()[0]); 
        System.out.println("Subject : " + message[i].getSubject()); 
        System.out.println("Sent Date : " + message[i].getSentDate()); 
    } 
    folder.close(false); 
    store.close(); 
    } 
    catch (MessagingException e) { 
      System.out.println("Error: " + e); 
     } 
    } 
} 

Answer 1

POP3協議不支持任何標誌，所以它不能告訴你消息是否被讀取。請參閱javadocs for the com.sun.mail.pop3 package for more information。

Answer 2

你可以嘗試使用如下，並試試看;

int messageCount = folder.getUnreadMessageCount(); 

if(messageCount>0){ 
Message[] messages = folder.getMessages(); 
}