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Author: filiphr

spring-integration-mail/src/main/java/org/springframework/integration/mail/AbstractMailReceiver.java

@@ -68,6 +68,7 @@
  * @author Dominik Simmen
  * @author Yuxin Wang
  * @author Ngoc Nhan
+ * @author Filip Hrisafov
  */
 public abstract class AbstractMailReceiver extends IntegrationObjectSupport implements MailReceiver, DisposableBean {
 
@@ -503,6 +504,12 @@ private Object byteArrayToContent(Map<String, Object> headers, ByteArrayOutputSt
 	}
 
 	private void postProcessFilteredMessages(Message[] filteredMessages) throws MessagingException {
+		// It is more intuitive use a local variable Message[] messages = filteredMessages;
+		// and then call setMessageFlagsAndMaybeDeleteMessages(messages); after the if, i.e. remove the else.
+		// However, in setMessageFlagsAndMaybeDeleteMessages we are calling Message#setFlag and Message#setFlags
+		// which have different implementations in different implementations of Message.
+		// e.g. IMAPMessage has a different implementation of those two methods.
+
 		// Copy messages to cause an eager fetch
 		if (this.headerMapper == null && (this.autoCloseFolder || this.simpleContent)) {
 			Message[] originalMessages = new Message[filteredMessages.length];

spring-integration-mail/src/test/java/org/springframework/integration/mail/ImapMailReceiverTests.java

@@ -109,6 +109,7 @@
  * @author Artem Bilan
  * @author Alexander Pinske
  * @author Dominik Simmen
+ * @author Filip Hrisafov
  */
 @SpringJUnitConfig
 @ContextConfiguration(