我需要JDK与Eclipse Helios和Tomcat 7.0.33一起使用吗？

Question

I want to develop dynamic web applications.

For this I am using Eclipse Helios and Tomcat 7.0.33. I have the JRE installed on my machine and I have provided the location of the JRE in the JAVA_HOME path.

But when I am running any servlet, I get the error:

" HTTP Status 404 " -- " The requested resource is not available "

Do I need a JDK in place of the JRE (meaning I have to set the path of the JDK in place of the JRE)? Or could there be another other reason why this error is happening?

Looking for Help!

Answer 1

If your servlets are already compiled then JRE will serve the purpose,

But they are compiled then you will JDK and other libraries( like servlet-api.jar, etc.) to compile you servlets.

In short JDK is for development where you want to develop something using Java.

And JRE is used when you already have compiled classes and you just want to run it.

You might want to refer to this :

What is the difference between JDK and JRE?

Answer 2

In theory, compiling with Eclipse's incremental compiler is sufficient. Running the application server with a JRE should be fine as well. I suppose your error is somewhere else. Anyway, I'd strongly recommend installing a JDK for developing a Java application. It comes with some handy tools and many 3rd party tools (Maven, eg) also require a real JDK compiler and can't work with Eclipse's built in compiler.

Answer 3

I had the same problem. The JDK was not the issue. After you compile your servlet you have to restart your tomcat server so it can load your class files before you try to access it through the web browser. No more 404 errors after that, servlets are running fine.