spring-integration - Spring集成IMAP-文件夹关闭异常

Question

我正在尝试使用 spring 集成获取基本的 Imapmailreceiver，但我无意中发现了一个粘性文件夹关闭异常。阅读电子邮件内容时，我经常收到文件夹关闭异常，但我能够正确获取主题。

非常感谢任何帮助。

<强>1。我的应用上下文如下

<int:channel id="emails"/>

<util:properties id="javaMailProperties">
    <prop key="mail.imap.socketFactory.class">javax.net.ssl.SSLSocketFactory</prop>
    <prop key="mail.imap.socketFactory.fallback">false</prop>
    <prop key="mail.store.protocol">imaps</prop>
    <prop key="mail.debug">false</prop>
</util:properties>
<int-mail:imap-idle-channel-adapter id="mailAdapter"
                             store-uri="ACTUALCREDENTIALHERE"
                              java-mail-properties="javaMailProperties"
                              channel="emails"
                              should-delete-messages="true"
                              auto-startup="false"
                              should-mark-messages-as-read="true" />
<int:service-activator id="receiveEmail" input-channel="emails" ref="MessageReceiver"/>
<bean id="MessageReceiver" class="org.springframework.integration.mail.imapidle.MessageReceiver" />
</beans>

<强>2。主APP如下

    ApplicationContext ac = new ClassPathXmlApplicationContext("/META-INF/spring/integration/gmail.xml");


 ImapIdleChannelAdapter ic=(ImapIdleChannelAdapter)ac
    .getBean("mailAdapter");

    ic.start();

<强>3。服务激活器如下

public class MessageReceiver {
    public void handle(javax.mail.Message message){
        MailToStringTransformer m2s = new MailToStringTransformer();
            m2s.setCharset("utf-8");


//payload instanceof MimeMultipart
            if (message instanceof MimeMessage) {
                try {
                 System.out.println("inside mimemessagehandler");
                   // javax.mail.Message mailMessage = (javax.mail.Message) payload;
                    System.out.println(message.getSubject());
                    System.out.println(getTextFromMessage(message));

                    Address[] receipts = message.getAllRecipients();
                    System.out.println("RECEIPIENTS MAIL ID");
                    if (receipts != null && receipts.length > 0) {
                        for (int i = 0; i < receipts.length; i++) {
                            System.out.println(((InternetAddress) receipts[i]).getAddress());
                        }
                    }

                    System.out.println("FROM MAIL ID");
                    Address[] froms = message.getFrom();
                    String email = froms == null ? null
                            : ((InternetAddress) froms[0]).getAddress();
                    System.out.println(email);

                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

            }

        }



    private static  String getTextFromMessage(javax.mail.Message message) throws Exception {
    String result = "";
    if (message.isMimeType("text/plain")) {
        result = message.getContent().toString();
    } else if (message.isMimeType("multipart/*")) {
        MimeMultipart mimeMultipart = (MimeMultipart) message.getContent();
        result = getTextFromMimeMultipart(mimeMultipart);
    }
    return result;
}

private static String getTextFromMimeMultipart(MimeMultipart mimeMultipart) throws Exception {
    String result = "";

    int count = mimeMultipart.getCount();
    System.out.println("CCC "+count);
    for (int i = 0; i < count; i++) {
       // mimeMultipart.toString()
        BodyPart bodyPart = mimeMultipart.getBodyPart(i);
        if (bodyPart.isMimeType("text/plain")) {
           result = mimeMultipart.toString();//(String) bodyPart.getContent();

        } else if (bodyPart.isMimeType("text/html")) {
            String html = (String) bodyPart.getContent();
            // result = result + "\n" + org.jsoup.Jsoup.parse(html).text();
        } else if (bodyPart.getContent() instanceof MimeMultipart) {
            result = result + getTextFromMimeMultipart((MimeMultipart) bodyPart.getContent());
        }
    }
    return result;
}

}

--- 异常(exception)情况

javax.mail.FolderClosedException

      at javax.mail.internet.MimeBodyPart.getContent(MimeBodyPart.java:659)
      at org.springframework.integration.mail.imapidle.MessageReceiver.getTextFromMimeMultipart(MessageReceiver.java:101)
      at org.springframework.integration.mail.imapidle.MessageReceiver.getTextFromMessage(MessageReceiver.java:83)
      at org.springframework.integration.mail.imapidle.MessageReceiver.handle(MessageReceiver.java:41)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at 

Answer 1

好吧，如果 Folder 已经关闭，看起来我们无法从 MimeBodyPart 获取内容。看起来我们在 AbstractMailReceiver.receive() 中遇到了这种情况:

            }
                return converted;
            }
            else {
                return filteredMessages;
            }
        }
        finally {
            MailTransportUtils.closeFolder(this.folder, this.shouldDeleteMessages);
        }

不确定为什么我们在接收后但在发送数据流之前关闭那里的文件夹，不过我建议您尝试为 ImapMailReceiver 使用 DefaultMailHeaderMapper。在那种情况下，MimeMessage 的内容在提到的 AbstractMailReceiver.receive() 内部转换为 org.springframework.messaging.Message:

if (this.headerMapper != null) {
                org.springframework.messaging.Message<?>[] converted =
                        new org.springframework.messaging.Message<?>[filteredMessages.length];
                int n = 0;
                for (MimeMessage message : filteredMessages) {
                    Map<String, Object> headers = this.headerMapper.toHeaders(message);
                    converted[n++] = getMessageBuilderFactory().withPayload(extractContent(message, headers))
                            .copyHeaders(headers)
                            .build();
                }
                return converted;
            }

与此同时，请提出 JIRA就此事，我们考虑修复 Folder.close() 不一致的问题。在我看来，根本不应该这样做，或者我们应该将它作为标题提供给最终用户，让他/她决定何时何地关闭文件夹。