java - 无法使用 Spring : javax. mail.FolderClosedException 读取电子邮件正文

Question

我正在尝试监听我的 Gmail 收件箱中收到的邮件。每次收到新邮件时，我都想查看它的主题和内容。

到目前为止，我有这个:

import java.io.IOException;

import javax.mail.BodyPart;
import javax.mail.Folder;
import javax.mail.internet.ContentType;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.mail.util.MimeMessageParser;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.integration.channel.DirectChannel;
import org.springframework.integration.mail.transformer.MailToStringTransformer;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHandler;
import org.springframework.messaging.MessagingException;


public class GmailInboundImapIdleAdapterTestApp {
    private static Log logger = LogFactory.getLog(GmailInboundImapIdleAdapterTestApp.class);

    public static void main (String[] args) throws Exception {
        @SuppressWarnings("resource")
        ClassPathXmlApplicationContext ac = new ClassPathXmlApplicationContext("/META-INF/spring/integration/gmail-imap-idle-config.xml");

        DirectChannel inputChannel = ac.getBean("receiveChannel", DirectChannel.class);

        inputChannel.subscribe(new MessageHandler() {
            public void handleMessage(Message<?> message){
                    MimeMessage mm = (MimeMessage) message.getPayload();
                    try {
                        System.out.println("Subject: "+mm.getSubject());
                        System.out.println("Body: "+readPlainContent(mm));
                    } 
                    catch (javax.mail.MessagingException e) {

                        System.out.println("MessagingException: "+e.getMessage());
                        e.printStackTrace();
                    }
                    catch (Exception e) {
                        System.out.println("Exception: "+e.getMessage());
                        e.printStackTrace();
                    }

            }
        });
    }

     private static String readHtmlContent(MimeMessage message) throws Exception {
            return new MimeMessageParser(message).parse().getHtmlContent();
        }

    private static String readPlainContent(MimeMessage message) throws Exception {
            return new MimeMessageParser(message).parse().getPlainContent();
        }
}

可以正确读取邮件主题。但邮件正文不太好。javax.mail.FolderClosedException 击中了我。如何解决这个问题？

Answer 1

正如 Gary 所说:simple-content="true" 或最近 autoCloseFolder = false:https://docs.spring.io/spring-integration/docs/5.2.0.RELEASE/reference/html/mail.html#mail-inbound

Starting with version 5.2, the autoCloseFolder option is provided on the mail receiver. Setting it to false doesn’t close the folder automatically after a fetch, but instead an IntegrationMessageHeaderAccessor.CLOSEABLE_RESOURCE header (see MessageHeaderAccessor API for more information) is populated into every message to producer from the channel adapter. It is the target application’s responsibility to call the close() on this header whenever it is necessary in the downstream flow: