/*
* Copyright 2002-2012 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.integration.samples.mailattachments.support;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import javax.mail.BodyPart;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.Part;
import javax.mail.internet.ContentType;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.ParseException;
import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;
import org.springframework.util.Assert;
/**
* Utility Class for parsing mail messages.
*
* @author Gunnar Hillert
* @since 2.2
*
*/
public final class EmailParserUtils {
private static final Logger LOGGER = Logger.getLogger(EmailParserUtils.class);
/** Prevent instantiation. */
private EmailParserUtils() {
throw new AssertionError();
}
/**
* Parses a mail message. The respective message can either be the root message
* or another message that is attached to another message.
*
* If the mail message is an instance of {@link String}, then a {@link EmailFragment}
* is being created using the email message's subject line as the file name,
* which will contain the mail message's content.
*
* If the mail message is an instance of {@link Multipart} then we delegate
* to {@link #handleMultipart(File, Multipart, javax.mail.Message, List)}.
*
* @param directory The directory for storing the message. If null this is the root message.
* @param mailMessage The mail message to be parsed. Must not be null.
* @param emailFragments Must not be null.
*/
public static void handleMessage(final File directory,
final javax.mail.Message mailMessage,
final List<EmailFragment> emailFragments) {
Assert.notNull(mailMessage, "The mail message to be parsed must not be null.");
Assert.notNull(emailFragments, "The collection of emailfragments must not be null.");
final Object content;
final String subject;
try {
content = mailMessage.getContent();
subject = mailMessage.getSubject();
} catch (IOException e) {
throw new IllegalStateException("Error while retrieving the email contents.", e);
} catch (MessagingException e) {
throw new IllegalStateException("Error while retrieving the email contents.", e);
}
final File directoryToUse;
if (directory == null) {
directoryToUse = new File(subject);
} else {
directoryToUse = new File(directory, subject);
}
if (content instanceof String) {
emailFragments.add(new EmailFragment(new File(subject), "message.txt", content));
}
else if (content instanceof Multipart) {
Multipart multipart = (Multipart) content;
handleMultipart(directoryToUse, multipart, mailMessage, emailFragments);
}
else {
throw new IllegalStateException("This content type is not handled - " + content.getClass().getSimpleName());
}
}
/**
* Parses any {@link Multipart} instances that contain text or Html attachments,
* {@link InputStream} instances, additional instances of {@link Multipart}
* or other attached instances of {@link javax.mail.Message}.
*
* Will create the respective {@link EmailFragment}s representing those attachments.
*
* Instances of {@link javax.mail.Message} are delegated to
* {@link #handleMessage(File, javax.mail.Message, List)}. Further instances
* of {@link Multipart} are delegated to
* {@link #handleMultipart(File, Multipart, javax.mail.Message, List)}.
*
* @param directory Must not be null
* @param multipart Must not be null
* @param mailMessage Must not be null
* @param emailFragments Must not be null
*/
public static void handleMultipart(File directory, Multipart multipart, javax.mail.Message mailMessage, List<EmailFragment> emailFragments) {
Assert.notNull(directory, "The directory must not be null.");
Assert.notNull(multipart, "The multipart object to be parsed must not be null.");
Assert.notNull(mailMessage, "The mail message to be parsed must not be null.");
Assert.notNull(emailFragments, "The collection of emailfragments must not be null.");
final int count;
try {
count = multipart.getCount();
if (LOGGER.isInfoEnabled()) {
LOGGER.info(String.format("Number of enclosed BodyPart objects: %s.", count));
}
}
catch (MessagingException e) {
throw new IllegalStateException("Error while retrieving the number of enclosed BodyPart objects.", e);
}
for (int i = 0; i < count; i++) {
final BodyPart bp;
try {
bp = multipart.getBodyPart(i);
}
catch (MessagingException e) {
throw new IllegalStateException("Error while retrieving body part.", e);
}
final String contentType;
String filename;
final String disposition;
final String subject;
try {
contentType = bp.getContentType();
filename = bp.getFileName();
disposition = bp.getDisposition();
subject = mailMessage.getSubject();
if (filename == null && bp instanceof MimeBodyPart) {
filename = ((MimeBodyPart) bp).getContentID();
}
}
catch (MessagingException e) {
throw new IllegalStateException("Unable to retrieve body part meta data.", e);
}
if (LOGGER.isInfoEnabled()) {
LOGGER.info(String.format("BodyPart - Content Type: '%s', filename: '%s', disposition: '%s', subject: '%s'",
new Object[]{contentType, filename, disposition, subject}));
}
if (Part.ATTACHMENT.equalsIgnoreCase(disposition)) {
LOGGER.info(String.format("Handdling attachment '%s', type: '%s'", filename, contentType));
}
final Object content;
try {
content = bp.getContent();
}
catch (IOException e) {
throw new IllegalStateException("Error while retrieving the email contents.", e);
}
catch (MessagingException e) {
throw new IllegalStateException("Error while retrieving the email contents.", e);
}
if (content instanceof String) {
if (Part.ATTACHMENT.equalsIgnoreCase(disposition)) {
emailFragments.add(new EmailFragment(directory, i + "-" + filename, content));
LOGGER.info(String.format("Handdling attachment '%s', type: '%s'", filename, contentType));
}
else {
final String textFilename;
final ContentType ct;
try {
ct = new ContentType(contentType);
}
catch (ParseException e) {
throw new IllegalStateException("Error while parsing content type '" + contentType + "'.", e);
}
if ("text/plain".equalsIgnoreCase(ct.getBaseType())) {
textFilename = "message.txt";
}
else if ("text/html".equalsIgnoreCase(ct.getBaseType())) {
textFilename = "message.html";
}
else {
textFilename = "message.other";
}
emailFragments.add(new EmailFragment(directory, textFilename, content));
}
}
else if (content instanceof InputStream) {
final InputStream inputStream = (InputStream) content;
final ByteArrayOutputStream bis = new ByteArrayOutputStream();
try {
IOUtils.copy(inputStream, bis);
}
catch (IOException e) {
throw new IllegalStateException("Error while copying input stream to the ByteArrayOutputStream.", e);
}
emailFragments.add(new EmailFragment(directory, filename, bis.toByteArray()));
}
else if (content instanceof javax.mail.Message) {
handleMessage(directory, (javax.mail.Message) content, emailFragments);
}
else if (content instanceof Multipart) {
final Multipart mp2 = (Multipart) content;
handleMultipart(directory, mp2, mailMessage, emailFragments);
}
else {
throw new IllegalStateException("Content type not handled: " + content.getClass().getSimpleName());
}
}
}
}