ImapMailReceiver不在只读文件夹上尝试任何存储操作（失败）[已限制]；

Question

我花了一天的时间来寻找这种异常的一些解释。我尝试以编程方式配置ImapMailReceiver和ImapIdleChannelAdapter。

在 Pro Spring Integration 书中，我没有找到有关此问题的任何教程，只是一些小信息。

public void loadMessages() {
        ImapIdleChannelAdapter imapIdleChannelAdapter = null;
        ImapMailReceiver imapMailReceiver = null;
        try {
            imapMailReceiver = new ImapMailReceiver("imaps://" + URLEncoder.encode(USERNAME, "UTF-8") + ":" + PASSWORD + "@imap.gmail.com:993/INBOX");
            imapMailReceiver.setShouldMarkMessagesAsRead(true);
            imapMailReceiver.setShouldDeleteMessages(false);

            Properties javaMailProperties = new Properties();
            javaMailProperties.put(MAIL_IMAP_SOCKET_FACTORY_CLASS, environment.getProperty(MAIL_IMAP_SOCKET_FACTORY_CLASS, SOCKET_FACTORY_CLASS));
            javaMailProperties.put(MAIL_IMAP_SOCKET_FACTORY_FALLBACK, environment.getProperty(MAIL_IMAP_SOCKET_FACTORY_FALLBACK, Boolean.class, SOCKET_FACTORY_FALLBACK));
            javaMailProperties.put(MAIL_STORE_PROTOCOL, environment.getProperty(MAIL_STORE_PROTOCOL, INBOX_MAIL_PROTOCOL));
            javaMailProperties.put(MAIL_DEBUG, environment.getProperty(MAIL_DEBUG, Boolean.class, MAIL_DEBUG_VAL));
            imapMailReceiver.setJavaMailProperties(javaMailProperties);

            imapMailReceiver.setJavaMailAuthenticator(new Authenticator() {
                @Override
                protected PasswordAuthentication getPasswordAuthentication() {
                    return new PasswordAuthentication(USERNAME, PASSWORD);
                }
            });


            ThreadPoolTaskScheduler threadPoolTaskScheduler = new ThreadPoolTaskScheduler();
            threadPoolTaskScheduler.setPoolSize(environment.getProperty(RECEIVE_MESSAGE_POOL_SIZE, Integer.class, DEFAULT_RECEIVE_MESSAGE_POOL_SIZE));
            threadPoolTaskScheduler.afterPropertiesSet();

            DirectChannel directChannel = new DirectChannel();
            directChannel.subscribe(new MessageHandler() {
                @Override
                public void handleMessage(Message<?> message) throws org.springframework.messaging.MessagingException {
                    LOGGER.info("Message: " + message);

                }
            });


            imapIdleChannelAdapter = new ImapIdleChannelAdapter(imapMailReceiver);
            imapIdleChannelAdapter.setAutoStartup(true);
            imapIdleChannelAdapter.setShouldReconnectAutomatically(true);
            imapIdleChannelAdapter.setTaskScheduler(threadPoolTaskScheduler);
            imapIdleChannelAdapter.setOutputChannel(directChannel);
            imapIdleChannelAdapter.start();
        } catch (IllegalStateException iex){
            LOGGER.debug("Receiving messages failed", iex);
            iex.printStackTrace();
            imapIdleChannelAdapter.stop();
            try{
                imapMailReceiver.destroy();
            } catch (Exception ex){
                LOGGER.debug("Impossible destroy imapMailReceiver", ex);
                ex.printStackTrace();
            }
        } catch (UnsupportedEncodingException uex) {
            LOGGER.debug("UnsupportedEncoding Exception", uex);
            uex.printStackTrace();
        }
    }

我的堆栈跟踪

09:13:27,429  INFO ImapMailReceiver:251 - attempting to receive mail from folder [INBOX]
09:13:34,840  WARN ImapIdleChannelAdapter:230 - error occurred in idle task
javax.mail.MessagingException: A13 NO STORE attempt on READ-ONLY folder (Failure) [THROTTLED];
  nested exception is:
    com.sun.mail.iap.CommandFailedException: A13 NO STORE attempt on READ-ONLY folder (Failure) [THROTTLED]
    at com.sun.mail.imap.IMAPMessage.setFlags(IMAPMessage.java:858)
    at javax.mail.Message.setFlag(Message.java:574)
    at org.springframework.integration.mail.AbstractMailReceiver.setMessageFlags(AbstractMailReceiver.java:317)
    at org.springframework.integration.mail.AbstractMailReceiver.postProcessFilteredMessages(AbstractMailReceiver.java:283)
    at org.springframework.integration.mail.AbstractMailReceiver.receive(AbstractMailReceiver.java:272)
    at org.springframework.integration.mail.ImapIdleChannelAdapter$IdleTask.run(ImapIdleChannelAdapter.java:216)
    at org.springframework.integration.mail.ImapIdleChannelAdapter$ReceivingTask.run(ImapIdleChannelAdapter.java:184)
    at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54)
    at org.springframework.scheduling.concurrent.ReschedulingRunnable.run(ReschedulingRunnable.java:81)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:178)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:292)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:722)

我也发现这样的决定

http://harikrishnan83.wordpress.com/2009/01/24/access-gmail-with-imap-using-
java-mail-api/

http://metoojava.wordpress.com/2010/03/21/java-
使用Javamailapi接收邮件的代码

但是我不明白为什么人们使用这种方式来获取消息（主要来源是这个决定，因为我什至在Spring Pro
Integration和Spring文档中都找不到这种解决方案）

请，任何人都可以向我解释1）在这种情况下，我应该使用ImapIdleChannelAdapter，并且当使用Session进行存储和连接到邮箱时。2）为什么现在出现异常“不对只读文件夹尝试存储”

Answer 1

您应该打电话imapMailReceiver.afterPropertiesSet()，这会切换this.folderOpenMode = Folder.READ_WRITE;。就您而言，它看起来就在这里：

imapMailReceiver.setJavaMailAuthenticator(new Authenticator() {
...
});

imapMailReceiver.afterPropertiesSet();

实际上，几乎所有的Spring Integration组件都应配置为Spring
Bean，并且Container将注意它们的初始化。新的4.0版本为JavaConfig提供了足够的选项：https ://spring.io/blog/2014/04/30/spring-
integration-4-0-released 。

对我来说，目前尚不清楚为什么默认情况下是这样，Folder.READ_ONLY并且对此没有任何影响。

随意提出JIRA问题：https :
//jira.spring.io/browse/INT

在这种情况下，我应该使用ImapIdleChannelAdapter，而在使用Session进行存储和连接到邮箱时。

实际上，这取决于您的邮件提供商。Spring
Integration提供了两个组件：Pop3MailReceiver和ImapMailReceiver。当然Imap更好，因为它不将消息提取到本地目录并支持Listener。Pop3您应该定期ping通。