java.lang.ClassCastException: javax.mail.Session cannot be cast to javax.mail.Session

» java » java.lang.ClassCastException: javax.mail.Session cannot be cast to javax.mail.Session

By : Codar

Date : November 25 2020, 07:22 PM

help you fix your problem This problem occurs in the server because the lib of Tomcat and you application both have their own copy of mail.jar (in WEB-INF/lib), so the classloaders can load two different Session.If you delete the mail.jarfrom your application, this problem will be solved.

code :

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java.lang.ClassCastException: javax.mail.internet.MimeMultipart cannot be cast to java.lang.String at NewClass.m

By : user3336075

Date : March 29 2020, 07:55 AM

fixed the issue. Will look into that further This is the code that is intended to fetch up the email from Gmail server. Along with it also brings the subject and the sender separately. The inbox that i am checking has 5 messages.(some read and some unread) I wanted the html content to be visible , so i used JEditorPane , The error is here

code :

JEditorPane ep = new JEditorPane("text/html" , (String)msgs[i].getContent());

java.lang.ClassCastException: java.lang.String cannot be cast to javax.mail.Multipart

By : Naveesh Doolhur

Date : March 29 2020, 07:55 AM

wish help you to fix your issue Understand the Exception First!!!
Your message content returning String and you are trying to type cast to Multipart.

code :

Object content = msg.getContent();  
if (content instanceof String)  
{  
    String body = (String)content;  
    ...  
}  
else if (content instanceof Multipart)  
{  
    Multipart mp = (Multipart)content;  
    ...  
}

maven jetty plugin : javax.mail.Session cannot be cast to javax.mail.Session

By : Corey Engelhart

Date : March 29 2020, 07:55 AM

This might help you OK, this is baffling me. I am trying to get the jetty maven plugin running with mail. I am restricted to 6.1.15 because we are using JDK 1.6. , I fixed it using the following property

code :

<configuration>
   <systemProperties>
     <systemProperty>
        <key>org.mortbay.jetty.webapp.parentLoaderPriority</key>
        <value>true</value>
      </systemProperty>
    </systemProperties>
 </configuration>

java.lang.ClassCastException: com.sun.mail.handlers.multipart_mixed cannot be cast to javax.activation.DataContentHandle

By : Adi Pasho

Date : March 29 2020, 07:55 AM

fixed the issue. Will look into that further Whenever a subclass apparently can't be typecasted to its legitimate superclass, you have duplicate classes, loaded by different classloaders. Find where you load the activation (superclass) classes, eliminate all but one (typically you'll need to eliminate the one class that your own project brings) and use the provided one from the framework.
The Exception message names the classes in question but omits the classloaders participating in the game, which is why the message, on first attempt to understand it, doesn't make much sense. As soon as you know about multiple classloaders, thus multiple instances of javax.activation.DataContentHandler, it makes more sense.

Java mail with attachment: ClassCastException on javax.mail.Multipart

By : Satya

Date : March 29 2020, 07:55 AM

To fix this issue I had the same problem with the JavaMail 1.5.1 and OSGi. Using msg.getContent() always returned an InputStream when called from an OSGi bundle while it works perfectly when called from a simple Java test program.
Setting the default CommandMap didn't work for me, but I found a solution here: