Question

我正在尝试使用android中的javamail api获取no.of消息，no.of已删除消息和no.of总消息的详细信息。但是对于已删除的消息，我总是得到-1。我找不到是什么原因/错误所以请帮助我。这是我的代码 class Readmails扩展了AsyncTask {

    Folder inbox;
    Folder inbox2;
     Properties props = System.getProperties();


    @Override
    protected String doInBackground(String... params) {
        // TODO Auto-generated method stub
         props.setProperty("mail.store.protocol", "imaps");
         try
         {
         /*  Create the session and get the store for read the mail. */
         Session session = Session.getDefaultInstance(props, null);
         Store store = session.getStore("imaps");
         store.connect("imap.gmail.com","test123@gmail.com", "testmycode12345");

         /*  Mention the folder name which you want to read. */
         inbox = store.getFolder("Inbox");

         System.out.println("No of Unread Messages : " + inbox.getUnreadMessageCount());
         System.out.println("No of New Messages : " +    inbox.getNewMessageCount());
         System.out.println("No of Deleted Messages : " +inbox.getDeletedMessageCount());
         System.out.println("No of total  Messages : " + inbox.getMessageCount());
         System.out.println("No of Type Messages : " + inbox.getType());
         /*Open the inbox using store.*/
         inbox.open(Folder.READ_ONLY);



         /*  Get the messages which is unread in the Inbox*/
         Message messages[] = inbox.search(new FlagTerm(new Flags(Flag.SEEN), false));

         /* Use a suitable FetchProfile    */
         FetchProfile fp = new FetchProfile();
         fp.add(FetchProfile.Item.ENVELOPE);
         fp.add(FetchProfile.Item.CONTENT_INFO);
         inbox.fetch(messages, fp);

         try
         {
         inbox.close(true);
         store.close();
         }
         catch (Exception ex)
         {
         System.out.println("Exception arise at the time of read mail");
         ex.printStackTrace();
         }
         }
         catch (NoSuchProviderException e)
         {
         e.printStackTrace();
         System.exit(1);
         }
         catch (MessagingException e)
         {
         e.printStackTrace();
         System.exit(2);
         }
        return null;
    }

}

Answer 1

在打开收件箱之前，您正在呼叫getDeletedMessageCount()。

请参阅代码中的this comment，它表示在已关闭的文件夹中返回-1。将您的来电移至inbox.open()

以上的println

为什么folder.getDeletedMessageCount（）总是返回-1？

1 个答案: