#487: Moved header filtering logic from MimeMessageParser to EmailConverter. Now, this is now done the build process in EmailConverter, so all headers remain preserved after initial parsing.

Author: bbottema

Diff for: modules/simple-java-mail/src/main/java/org/simplejavamail/converter/EmailConverter.java

@@ -14,6 +14,7 @@
 import org.simplejavamail.api.email.EmailPopulatingBuilder;
 import org.simplejavamail.api.email.OriginalSmimeDetails;
 import org.simplejavamail.api.email.OriginalSmimeDetails.SmimeMode;
+import org.simplejavamail.api.internal.general.HeadersToIgnoreWhenParsingExternalEmails;
 import org.simplejavamail.api.internal.outlooksupport.model.EmailFromOutlookMessage;
 import org.simplejavamail.api.internal.outlooksupport.model.OutlookMessage;
 import org.simplejavamail.api.internal.smimesupport.builder.SmimeParseResult;
@@ -644,7 +645,15 @@ private static EmailPopulatingBuilder buildEmailFromMimeMessage(@NotNull final E
 		if (parsed.getReplyToAddresses() != null) {
 			builder.withReplyTo(parsed.getReplyToAddresses().getPersonal(), parsed.getReplyToAddresses().getAddress());
 		}
-		builder.withHeaders(parsed.getHeaders());
+
+		for (val headerEntry : parsed.getHeaders().entrySet()) {
+			if (!HeadersToIgnoreWhenParsingExternalEmails.shouldIgnoreHeader(headerEntry.getKey())) {
+				for (Object headerValue : headerEntry.getValue()) {
+					builder.withHeader(headerEntry.getKey(), headerValue);
+				}
+			}
+		}
+
 		if (parsed.getDispositionNotificationTo() != null) {
 			builder.withDispositionNotificationTo(parsed.getDispositionNotificationTo());
 		}

Diff for: modules/simple-java-mail/src/main/java/org/simplejavamail/converter/internal/mimemessage/MimeMessageParser.java

@@ -152,7 +152,6 @@ private static MimeDataSource parseAttachment(@Nullable final String contentId,
 				.build();
 	}
 
-	@SuppressWarnings("StatementWithEmptyBody")
 	private static void parseHeader(final DecodedHeader header, @NotNull final ParsedMimeMessageComponents parsedComponents) {
 		val headerValue = decodeText(header.getValue());
 		val headerName = decodeText(header.getName());
@@ -163,13 +162,11 @@ private static void parseHeader(final DecodedHeader header, @NotNull final Parse
 			parsedComponents.returnReceiptTo = createAddress(headerValue, "Return-Receipt-To");
 		} else if (isEmailHeader(header, "Return-Path")) {
 			parsedComponents.bounceToAddress = createAddress(headerValue, "Return-Path");
-		} else if (!HeadersToIgnoreWhenParsingExternalEmails.shouldIgnoreHeader(headerName)) {
+		} else {
 			if (!parsedComponents.headers.containsKey(headerName)) {
 				parsedComponents.headers.put(headerName, new ArrayList<>());
 			}
 			parsedComponents.headers.get(headerName).add(MimeUtility.unfold(headerValue));
-		} else {
-			// header recognized, but not relevant (see #HEADERS_TO_IGNORE)
 		}
 	}