An internal error occurred during: "Loading descriptor for <Web Project>.". java.lang.NullPointerException

Question

I just downloaded Eclipse Luna on my new laptop and as soon as I have created a new Dynamic Web project and try to expand the project in the explorer, I get this error message:

"An internal error occurred during: "Loading descriptor for WebProjectTest.".
java.lang.NullPointerException"

I initially ignored the message, but when I go to add a servlet through the 'create servlet' window and type a name for the class I'm unable to press 'next'.

I have Java 1.7 installed and had no problems at all using Eclipse Juno on my old laptop

Answer 1

I just had this problem and realized that it was because I had accidentally downloaded the non-J2EE version of Eclipse. It looks like the plugins and Eclipse itself does not recognize that you're asking it to to J2EE things in a non-J2EE app and will throw mysterious errors and exceptions like this. My solution was to start over and download the J2EE version of Eclipse and reload the project in that.

I think it might be possible to upgrade a non-J2EE Eclipse by downloading all of the right tools but it is probably simpler to just re-download it.