#107: Implemented forwarding, improved replying

#102: When parsing MimeMessage to Email, also include the Return-Path as bounceToAddress
#95: When parsing MimeMessage to Email, also include the Return-Receipt-To
#93: When parsing MimeMessage to Email, also include the Disposition-Notification-To
Other: Overhauled MimeMessageParser to be more useful and usable (including better exceptions)

src/main/java/org/simplejavamail/converter/EmailConverter.java

@@ -2,6 +2,7 @@
 
 import org.simplejavamail.converter.internal.mimemessage.MimeMessageHelper;
 import org.simplejavamail.converter.internal.mimemessage.MimeMessageParser;
+import org.simplejavamail.converter.internal.mimemessage.MimeMessageParser.ParsedMimeMessageComponents;
 import org.simplejavamail.converter.internal.msgparser.OutlookMessageParser;
 import org.simplejavamail.email.Email;
 import org.simplejavamail.email.Recipient;
@@ -14,7 +15,6 @@
 import javax.annotation.Nonnull;
 import javax.mail.MessagingException;
 import javax.mail.Session;
-import javax.mail.internet.AddressException;
 import javax.mail.internet.InternetAddress;
 import javax.mail.internet.MimeMessage;
 import java.io.ByteArrayInputStream;
@@ -51,12 +51,9 @@ private EmailConverter() {
 	 * @param mimeMessage The MimeMessage from which to create the {@link Email}.
 	 */
 	public static Email mimeMessageToEmail(@Nonnull final MimeMessage mimeMessage) {
+		checkNonEmptyArgument(mimeMessage, "mimeMessage");
 		final Email email = new Email(false);
-		try {
-			fillEmailFromMimeMessage(email, checkNonEmptyArgument(mimeMessage, "mimeMessage"));
-		} catch (MessagingException | IOException e) {
-			throw new EmailConverterException(format(EmailConverterException.PARSE_ERROR_MIMEMESSAGE, e.getMessage()), e);
-		}
+		fillEmailFromMimeMessage(email, MimeMessageParser.parseMimeMessage(mimeMessage));
 		return email;
 	}
 
@@ -231,58 +228,53 @@ public static String outlookMsgToEML(@Nonnull final InputStream outloookMsgInput
 		Helpers
 	 */
 
-	private static void fillEmailFromMimeMessage(@Nonnull final Email email, @Nonnull final MimeMessage mimeMessage)
-			throws MessagingException, IOException {
+	private static void fillEmailFromMimeMessage(@Nonnull final Email email, @Nonnull final ParsedMimeMessageComponents parsed) {
 		checkNonEmptyArgument(email, "email");
-		checkNonEmptyArgument(mimeMessage, "mimeMessage");
-		final MimeMessageParser parser = new MimeMessageParser(mimeMessage).parse();
-		final InternetAddress from = parser.getFrom();
-		email.setFromAddress(from.getPersonal(), from.getAddress());
-		final InternetAddress replyTo = parser.getReplyTo();
-		email.setReplyToAddress(replyTo.getPersonal(), replyTo.getAddress());
-		for (final Map.Entry<String, Object> header : parser.getHeaders().entrySet()) {
-			if (!fillPredefinedHeader(email, header)) {
-				email.addHeader(header.getKey(), header.getValue());
-			}
+		checkNonEmptyArgument(parsed, "parsedMimeMessageComponents");
+		if (parsed.getFromAddress() != null) {
+			email.setFromAddress(parsed.getFromAddress().getPersonal(), parsed.getFromAddress().getAddress());
+		}
+		if (parsed.getReplyToAddresses() != null) {
+			email.setReplyToAddress(parsed.getReplyToAddresses().getPersonal(), parsed.getReplyToAddresses().getAddress());
+		}
+		for (final Map.Entry<String, Object> header : parsed.getHeaders().entrySet()) {
+			email.addHeader(header.getKey(), header.getValue());
 		}
-		email.setId(mimeMessage.getMessageID());
-		for (final InternetAddress to : parser.getTo()) {
+		InternetAddress dnTo = parsed.getDispositionNotificationTo();
+		if (dnTo != null) {
+			email.setDispositionNotificationTo(new Recipient(dnTo.getPersonal(), dnTo.getAddress(), null));
+		}
+		InternetAddress rrTo = parsed.getReturnReceiptTo();
+		if (rrTo != null) {
+			email.setReturnReceiptTo(new Recipient(rrTo.getPersonal(), rrTo.getAddress(), null));
+		}
+		InternetAddress bTo = parsed.getBounceToAddress();
+		if (bTo != null) {
+			email.setBounceToRecipient(new Recipient(bTo.getPersonal(), bTo.getAddress(), null));
+		}
+		email.setId(parsed.getMessageId());
+		for (final InternetAddress to : parsed.getToAddresses()) {
 			email.addNamedToRecipients(to.getPersonal(), to.getAddress());
 		}
 		//noinspection QuestionableName
-		for (final InternetAddress cc : parser.getCc()) {
+		for (final InternetAddress cc : parsed.getCcAddresses()) {
 			email.addNamedCcRecipients(cc.getPersonal(), cc.getAddress());
 		}
-		for (final InternetAddress bcc : parser.getBcc()) {
+		for (final InternetAddress bcc : parsed.getBccAddresses()) {
 			email.addNamedBccRecipients(bcc.getPersonal(), bcc.getAddress());
 		}
-		email.setSubject(parser.getSubject());
-		email.setText(parser.getPlainContent());
-		email.setTextHTML(parser.getHtmlContent());
-		for (final Map.Entry<String, DataSource> cid : parser.getCidMap().entrySet()) {
+		email.setSubject(parsed.getSubject() != null ? parsed.getSubject() : "");
+		email.setText(parsed.getPlainContent());
+		email.setTextHTML(parsed.getHtmlContent());
+		for (final Map.Entry<String, DataSource> cid : parsed.getCidMap().entrySet()) {
 			final String cidName = checkNonEmptyArgument(cid.getKey(), "cid.key");
 			email.addEmbeddedImage(extractCID(cidName), cid.getValue());
 		}
-		for (final Map.Entry<String, DataSource> attachment : parser.getAttachmentList().entrySet()) {
+		for (final Map.Entry<String, DataSource> attachment : parsed.getAttachmentList().entrySet()) {
 			email.addAttachment(extractCID(attachment.getKey()), attachment.getValue());
 		}
 	}
 
-	private static boolean fillPredefinedHeader(@Nonnull Email email, @Nonnull Map.Entry<String, Object> header) throws AddressException {
-		if (header.getKey().equals("Disposition-Notification-To")) {
-			email.setUseDispositionNotificationTo(true);
-			InternetAddress internetAddress = new InternetAddress((String) header.getValue());
-			email.setDispositionNotificationTo(new Recipient(internetAddress.getPersonal(), internetAddress.getAddress(), null));
-			return true;
-		} else if (header.getKey().equals("Return-Receipt-To")) {
-			email.setUseReturnReceiptTo(true);
-			InternetAddress internetAddress = new InternetAddress((String) header.getValue());
-			email.setReturnReceiptTo(new Recipient(internetAddress.getPersonal(), internetAddress.getAddress(), null));
-			return true;
-		}
-		return false;
-	}
-
 	private static void fillEmailFromOutlookMessage(@Nonnull final Email email, @Nonnull final OutlookMessage outlookMessage) {
 		checkNonEmptyArgument(email, "email");
 		checkNonEmptyArgument(outlookMessage, "outlookMessage");

src/main/java/org/simplejavamail/converter/EmailConverterException.java

@@ -12,8 +12,6 @@ class EmailConverterException extends MailException {
 
 	static final String PARSE_ERROR_EML = "Error parsing EML data: %s";
 
-	static final String PARSE_ERROR_MIMEMESSAGE = "Error parsing MimeMessage: %s";
-
 	public EmailConverterException(final String message, final Exception cause) {
 		super(message, cause);
 	}

src/main/java/org/simplejavamail/converter/internal/mimemessage/MimeMessageHelper.java

@@ -89,19 +89,20 @@ protected void updateMessageID() throws MessagingException {
 		setRecipients(email, message);
 		// fill multipart structure
 		setTexts(email, messageRoot.multipartAlternativeMessages);
+		configureForwarding(email, messageRoot.multipartRootMixed);
 		setEmbeddedImages(email, messageRoot.multipartRelated);
-		setAttachments(email, messageRoot.multipartRoot);
-		message.setContent(messageRoot.multipartRoot);
+		setAttachments(email, messageRoot.multipartRootMixed);
+		message.setContent(messageRoot.multipartRootMixed);
 		setHeaders(email, message);
 		message.setSentDate(new Date());
 
 		if (email.isApplyDKIMSignature()) {
 			return signMessageWithDKIM(message, email);
 		}
-
+		
 		return message;
 	}
-
+	
 	/**
 	 * Fills the {@link Message} instance with recipients from the {@link Email}.
 	 *
@@ -157,6 +158,24 @@ private static void setTexts(final Email email, final MimeMultipart multipartAlt
 			multipartAlternativeMessages.addBodyPart(messagePartHTML);
 		}
 	}
+
+	/**
+	 * If provided, adds the {@code emailToForward} as a MimeBodyPart to the mixed multipart root.
+	 * <p>
+	 * <strong>Note:</strong> this is done without setting {@code Content-Disposition} so email clients can choose
+	 * how to display embedded forwards. Most client will show the forward as inline, some may show it as attachment.
+	 */
+	private static void configureForwarding(@Nonnull final Email email, @Nonnull final MimeMultipart multipartRootMixed) {
+		if (email.getEmailToForward() != null) {
+			try {
+				final BodyPart fordwardedMessage = new MimeBodyPart();
+				fordwardedMessage.setContent(email.getEmailToForward(), "message/rfc822");
+				multipartRootMixed.addBodyPart(fordwardedMessage);
+			} catch (MessagingException e) {
+				e.printStackTrace();
+			}
+		}
+	}
 
 	/**
 	 * Fills the {@link Message} instance with the embedded images from the {@link Email}.
@@ -307,7 +326,7 @@ public static MimeMessage signMessageWithDKIM(final MimeMessage message, final E
 			dkimSigner.setZParam(false);
 			return new DkimMessage(message, dkimSigner);
 		} catch (IOException | NoSuchAlgorithmException | InvalidKeySpecException | MessagingException e) {
-			throw new MimeMessageException(MimeMessageException.INVALID_DOMAINKEY, e);
+			throw new MimeMessageParseException(MimeMessageParseException.INVALID_DOMAINKEY, e);
 		}
 	}
 
@@ -316,44 +335,47 @@ public static MimeMessage signMessageWithDKIM(final MimeMessage message, final E
 	 * using JavaMail.<br> <br> The constructor creates a new email message constructed from {@link MimeMultipart} as follows:
 	 * <p/>
 	 * <pre>
-	 * - root
+	 * - mixed root
 	 * 	- related
 	 * 		- alternative
 	 * 			- mail tekst
 	 * 			- mail html tekst
 	 * 		- embedded images
+	 * 	- forwarded message
 	 * 	- attachments
 	 * </pre>
 	 *
 	 * @author Benny Bottema
 	 */
 	private static class MimeEmailMessageWrapper {
 
-		private final MimeMultipart multipartRoot;
+		private final MimeMultipart multipartRootMixed;
 
 		private final MimeMultipart multipartRelated;
 
 		private final MimeMultipart multipartAlternativeMessages;
 
 		/**
 		 * Creates an email skeleton structure, so that embedded images, attachments and (html) texts are being processed properly.
+		 *
+		 * Some more <a href="https://blogs.technet.microsoft.com/exchange/2011/04/21/mixed-ing-it-up-multipartmixed-messages-and-you/.">helpful reading material</a>.
 		 */
 		MimeEmailMessageWrapper() {
-			multipartRoot = new MimeMultipart("mixed");
+			multipartRootMixed = new MimeMultipart("mixed");
 			final MimeBodyPart contentRelated = new MimeBodyPart();
 			multipartRelated = new MimeMultipart("related");
 			final MimeBodyPart contentAlternativeMessages = new MimeBodyPart();
 			multipartAlternativeMessages = new MimeMultipart("alternative");
 			try {
 				// construct mail structure
-				multipartRoot.addBodyPart(contentRelated);
+				multipartRootMixed.addBodyPart(contentRelated);
 				contentRelated.setContent(multipartRelated);
 				multipartRelated.addBodyPart(contentAlternativeMessages);
 				contentAlternativeMessages.setContent(multipartAlternativeMessages);
 			} catch (final MessagingException e) {
-				throw new MimeMessageException(e.getMessage(), e);
+				throw new MimeMessageParseException(e.getMessage(), e);
 			}
 		}
 
 	}
-}
+}

src/main/java/org/simplejavamail/converter/internal/mimemessage/MimeMessageParseException.java

@@ -0,0 +1,41 @@
+package org.simplejavamail.converter.internal.mimemessage;
+
+import org.simplejavamail.MailException;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import static org.simplejavamail.internal.util.Preconditions.checkNonEmptyArgument;
+
+/**
+ * This exception is used to communicate errors during parsing of a {@link javax.mail.internet.MimeMessage}.
+ *
+ * @author Benny Bottema
+ */
+@SuppressWarnings("serial")
+class MimeMessageParseException extends MailException {
+
+	static final String INVALID_DOMAINKEY = "Error signing MimeMessage with DKIM";
+	static final String ERROR_PARSING_FROMADDRESS = "Error parsing from-address";
+	static final String ERROR_PARSING_ADDRESS = "Error parsing [%s] address";
+	static final String ERROR_PARSING_DISPOSITION = "Error parsing MimeMessage disposition";
+	static final String ERROR_PARSING_CONTENT = "Error parsing MimeMessage Content";
+	static final String ERROR_PARSING_MULTIPART_COUNT = "Error parsing MimeMessage multipart count";
+	static final String ERROR_GETTING_BODYPART_AT_INDEX = "Error getting bodypart at index %s";
+	static final String ERROR_GETTING_CONTENT_ID = "Error getting content ID";
+	static final String ERROR_GETTING_FILENAME = "Error getting file name";
+	static final String ERROR_GETTING_ALL_HEADERS = "Error getting all headers";
+	static final String ERROR_GETTING_DATAHANDLER = "Error getting data handler";
+	static final String ERROR_GETTING_CONTENT_TYPE = "Error getting content type";
+	static final String ERROR_GETTING_INPUTSTREAM = "Error getting input stream";
+	static final String ERROR_READING_CONTENT = "Error reading content";
+	static final String ERROR_DECODING_TEXT = "Error decoding text";
+	static final String ERROR_GETTING_RECIPIENTS = "Error getting [%s] recipient types";
+	static final String ERROR_GETTING_SUBJECT = "Error getting subject";
+	static final String ERROR_GETTING_MESSAGE_ID = "Error getting message ID";
+	static final String ERROR_PARSING_REPLY_TO_ADDRESSES = "Error parsing replyTo addresses";
+
+	MimeMessageParseException(@Nonnull final String message, @Nullable final Exception cause) {
+		super(checkNonEmptyArgument(message, "message"), cause);
+	}
+}