We help IT Professionals succeed at work.

Run-time error while using a third-party jar file in swing application

vsk76 asked
Last Modified: 2013-12-14
I am using a third-party tool - mdate.jar to use the lt.monarch.swing.JDateField class in my Java Swing application.
When I try to create an object of the class like -
import lt.monarch.swing.JDateField;
private JDateField strtDate = new JDateField();
it compiles down perfectly but I get a run time error as follows:
Exception in thread "AWT-EventQueue-3" java.lang.NoClassDefFoundError: lt/monarch/swing/JDateField

Please help me if I am missing something to achieve this.
Watch Question

Mick BarryJava Developer
Top Expert 2010

you need to include the jar in your classpath


I have included it in the classpath, but even then I am getting the same error.

Am I missing something else? Please suggest
Mick BarryJava Developer
Top Expert 2010

how are you running it?


I compile down all my classes onto the server and access the applets from the asps.

It is a web application and I have also placed the jar in the web-inf folder. Also I have placed the mdate.jar in the jre\lib\ext folder.

Also as you said I have included it in the classpath.

Java Developer
Top Expert 2010
This one is on us!
(Get your first solution completely free - no credit card required)

Gain unlimited access to on-demand training courses with an Experts Exchange subscription.

Get Access
Why Experts Exchange?

Experts Exchange always has the answer, or at the least points me in the correct direction! It is like having another employee that is extremely experienced.

Jim Murphy
Programmer at Smart IT Solutions

When asked, what has been your best career decision?

Deciding to stick with EE.

Mohamed Asif
Technical Department Head

Being involved with EE helped me to grow personally and professionally.

Carl Webster
CTP, Sr Infrastructure Consultant
Empower Your Career
Did You Know?

We've partnered with two important charities to provide clean water and computer science education to those who need it most. READ MORE

Ask ANY Question

Connect with Certified Experts to gain insight and support on specific technology challenges including:

  • Troubleshooting
  • Research
  • Professional Opinions
Unlock the solution to this question.
Join our community and discover your potential

Experts Exchange is the only place where you can interact directly with leading experts in the technology field. Become a member today and access the collective knowledge of thousands of technology experts.

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.