javax.activation.UnsupportedDataTypeException: no object DCH for MIME type multipart/mixed; boundary

Question

Currently I'm inline of writing a code that will be listening to a directory. when the directory is updated with .apk file, I'll send a mail with this .apk file to a gmail account. I'm using Jnotify and JAVA Mail in my program.

The Error I'm getting is,

javax.mail.MessagingException: IOException while sending message;
  nested exception is:
javax.activation.UnsupportedDataTypeException: no object DCH for MIME type multipart/mixed; boundary="----=_Part_0_145238.1392728439484"

I looked for the solutions given in the stackoverflow for help but none of them where helpful.

Thanks in Advance

public void fileCreated(int wd, String rootPath, String name) {
    print("created " + rootPath + " : " + name);

    if (name.contains(".apk"))
      SendEmail(name);
    else
        System.out.println("Not the APK file");
}

void SendEmail(String strname){
    String Path = "D:/POC/Email/apk folder/"+strname;
    System.out.println("Path->" + Path);

    Properties props = new Properties();
    props.put("mail.smtp.host","173.194.78.108");
    props.put("mail.smtp.socketFactory.port", "465");
    props.put("mail.smtp.socketFactory.class","javax.net.ssl.SSLSocketFactory");
    props.put("mail.smtp.auth","true");
    props.put("mail.smtp.port","465");

    System.out.println("Properties has been set properly");

    Session session = Session.getDefaultInstance(props,
        new javax.mail.Authenticator(){
            protected PasswordAuthentication getPasswordAuthentication(){
                return new PasswordAuthentication("SenderEmailID@gmail.com", "senderPassword");
            }
        }
    );

    System.out.println("Session Created successfully");

    try{
        Message message = new MimeMessage(session); 
        message.setFrom(new InternetAddress("SenderEmailID@gmail.com"));
        message.setRecipients(Message.RecipientType.TO, InternetAddress.parse("ToReceiverEmailID@gmail.com"));
        message.setSubject("Android : " + strname);

        MimeBodyPart msgbody = new MimeBodyPart();
        msgbody.setText("This is the message content which is sent using JAVA MAIL 1.4.5");
        Multipart mulpart = new MimeMultipart();
        mulpart.addBodyPart(msgbody);

        //Attachement Starts here.
        msgbody = new MimeBodyPart();
        javax.activation.DataSource source = new FileDataSource(Path);
        msgbody.setDataHandler(new DataHandler(source));
        msgbody.setFileName(strname);
        message.setContent(mulpart);

        System.out.println("Attached the message going to start transporting the mail");

        //If I've the code before sending the email is getting sent but without attachment. 
        //Thread.currentThread().setContextClassLoader( getClass().getClassLoader() );

        Transport.send(message);
        System.out.println("Mail Sent successfully");
    }
    catch(MessagingException msg){
        msg.printStackTrace();
    }
    catch(Exception e){
        e.printStackTrace();
    }
}

Answer 1

JavaMail depends on some configuration files to map MIME types to Java classes (e.g., multipart/mixed to javax.mail.internet.MimeMultipart). These configuration files are loaded using the ClassLoader for the application. If the ClassLoader doesn't function properly, these configuration files won't be found.

You can simply add below lines .. that solves the issue .

MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap(); 
mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html"); 
mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml"); 
mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain"); 
mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed"); 
mc.addMailcap("message/rfc822;; x-java-content- handler=com.sun.mail.handlers.message_rfc822"); 

Answer 2

This issue can get a solution by taking up the below two steps.

1. Make sure java mail is 1.4.7.(Previously I used 1.4.5 which led to all confusions). Download it from http://www.oracle.com/technetwork/java/index-138643.html
2. Add this piece of code before sending the message:

    Thread.currentThread().setContextClassLoader( getClass().getClassLoader() );

Answer 3

Adding the current thread before sending the email is the solution:

Thread.currentThread().setContextClassLoader( getClass().getClassLoader() );

Answer 4

I am busy converting a Java 8 project to Java 10. At the same time I have been updating all of the dependencies. I was getting a similar exception and none of the above solutions worked for me.

I have the following in my pom.xml:

<dependency>
    <groupId>com.sun.mail</groupId>
    <artifactId>javax.mail</artifactId>
    <version>1.6.1</version>
</dependency>

I did a bit more research and found the following link:

http://www.jguru.com/faq/view.jsp?EID=237257

So I tried adding the following dependency to my pom.xml:

<dependency>
    <groupId>javax.activation</groupId>
    <artifactId>activation</artifactId>
    <version>1.1.1</version>
 </dependency>

That fixed the problem, I was able to send mail with attachments again.

Answer 5

The answer from Som worked for me. However I had to modify the mappings as I was using JavaMail DSN, and needed those mailcap entries also (included below, including Som's answer):

// Original answer from Som:
MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap();
mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html");
mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml");
mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain");
mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed");
mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822");

// Additional elements to make DSN work 
mc.addMailcap("multipart/report;;  x-java-content-handler=com.sun.mail.dsn.multipart_report");
mc.addMailcap("message/delivery-status;; x-java-content-handler=com.sun.mail.dsn.message_deliverystatus");
mc.addMailcap("message/disposition-notification;; x-java-content-handler=com.sun.mail.dsn.message_dispositionnotification");
mc.addMailcap("text/rfc822-headers;;   x-java-content-handler=com.sun.mail.dsn.text_rfc822headers");

As it turns out, it was adding the DSN JAR into my fat JAR (using shadowJar/Gradle) that caused the problem: the META-INF/mailcap from the DSN jar was overwriting the core one.

Answer 6

Tell me more about the environment in which your code is running. What JDK are you using? Are you running in an application server?

The JavaBeans Activation Framework (JAF) looks for configuration files that tell how to map MIME types to the Java classes (DataContentHandlers) that handle them. It uses the ClassLoader to find the configuration files. If there are problems with the ClassLoader, the configuration files might not be found.

You might want to try the workaround described here, but of course it would be better to determine the root cause of the problem for you.

Finally, you might want to simplify your program by fixing some of these common JavaMail mistakes.

Answer 7

If it's a android project, it's highly possible the proguard stripped out unused classes by mistake, please add the following lines in the proguard file to fix the problem without modifying the code directly:

-keep class com.sun.mail.handlers.**
-dontwarn com.sun.mail.handlers.handler_base

Answer 8

Som's answer (MailcapCommandMap) worked for me with Spring war Portlets in Liferay 7.1 ga1. However, I had to remove Tomcat's mail.jar from tomcat/lib/ext and replace it with javax.mail-1.6.2.jar, then make sure the dependency is scoped as provided in the project's pom.xml:

<dependency>
    <groupId>com.sun.mail</groupId>
    <artifactId>javax.mail</artifactId>
    <version>1.6.2</version>
    <scope>provided</scope>
</dependency>

Answer 9

Under OSGI, the following workaround allows the javax.activation bundle to load the "META-INF/mailcap" resource from the javax.mail bundle :

Thread.currentThread().setContextClassLoader(javax.mail.Message.class.getClassLoader());

Note : character sets conversions may have limitations with this workaround...

Answer 10

If your build.xml does this: zipfileset src="javamail-1.4.7/mail.jar" excludes="META-INF/"**

Then you're stripping out the configuration information.

Answer 11

Even I had faced same issue. I tried different versions of javamail it didnt work. The problem was Transport.send() was using MailCapCommandMap class from the default java jdk (JAVA 8 in my case) that loaded outdated mailcap files.

So I used the latest version of JAVA after which it used MailCapCommandMap from the activation package which loaded the correct mailcap file.

If any anyone faces same problem in future just add a breakpoint in MailCapCommandMap classes available so that u know which mailcap file it is using.

Answer 12

A similar problem appeared when running a Java 8 S/MIME parsing code on Java 12. Relevant (missing) DCH was for a custom MIME type message/disposition-notification.

Unlike in old Java's native javax.activation.ObjectDataContentHandler, the external javax.activation:activation library for Java 9+, does not seem to tolerate "unknown" MIME types; earlier, multipart "parts" with such custom content-types (not found in mailcap meta-files) were still consumed if they contained byte[] or String content - but not anymore.

// old native
    public void writeTo(Object obj, String mimeType, OutputStream os) throws IOException {
        if (this.dch != null) {
            this.dch.writeTo(obj, mimeType, os);
        } else if (obj instanceof byte[]) {
            os.write((byte[])((byte[])obj));
        } else {
            if (!(obj instanceof String)) {
                throw new UnsupportedDataTypeException("no object DCH for MIME type " + this.mimeType);
            }

            OutputStreamWriter osw = new OutputStreamWriter(os);
            osw.write((String)obj);
            osw.flush();
        }
    }


// new javax.activation:activation
    public void writeTo(Object obj, String mimeType, OutputStream os)
                        throws IOException {
    if (dch != null)
        dch.writeTo(obj, mimeType, os);
    else
        throw new UnsupportedDataTypeException(
                "no object DCH for MIME type " + this.mimeType);
    }

Solution was to define an entry for message/disposition-notification (it can be safely interpreted as text) in a mailcap file; technically similar to @Som's answer, but we all love no-code solutions, right?

message/disposition-notification;;x-java-content-handler=com.sun.mail.handlers.text_plain

and bundle it into the JAR (classpath); e.g. with Maven:

    <build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>META-INF/mailcap</include>
                </includes>
            </resource>
        </resources>
    </build>

Also noteworthy: setting a -Djavax.activation.debug=true system property on the JVM, greatly helps in tracing issues related to such mailcap loading, handling, fallbacks etc.