Why am I getting this NoClassDefFoundError from my code? - noclassdeffounderror

Question

I have been trying to use a Jar file as a library in my code, and it compiles fine. However, at runtime, I keep getting the NoClassDefFoundError message. Why is this happening? I have included the Jar file in the compile path and the runtime path too.
Here is the error message:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
at org.apache.pdfbox.cos.COSDocument.(COSDocument.java:51)
at org.apache.pdfbox.pdmodel.PDDocument.(PDDocument.java:136)
at processing.PDFToJPG.main(PDFToJPG.java:58)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 3 more
Here is my code:
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
public static void main(String[] args) {
try {
PDDocument doc = new PDDocument();
} catch (Exception e) {
e.printStackTrace();
}
}
I am using NetBeans IDE as well as Windows 10
This is my setting for compile classpath:
[
This is my setting for runtime classpath:
[
EDIT: Thank you for your help, it really worked. All i needed to do was to download the dependencies Jar file, not editing the classpath like what i have been trying to do

Answer 1

I think you need another jars besides the one you have already included. Try to add common-logging 1.4. Apparently, there is a dependency between pdfbox1.8.jar and this jar as stated on their site.
EDIT: There are more dependencies fontbox and jempbox to take in account as well.
EDIT2: I made a zip with all dependencies needed you can download it here.

Answer 2

I agree with Aurelien's post: it looks like you are missing Apache Commons Logging - and other runtime dependencies.
You might want to consider creating your project as a 'Maven' Project (And Netbeans supports Maven pretty well): and then adding 'pdfbox' as a 'dependency'; this should make life a lot easier for you - since Maven will fetch any other required dependencies.
You can get the 'Maven Coordinates' for the various PDFBox versions from here:
http://mvnrepository.com/artifact/org.apache.pdfbox/pdfbox
If you want to build your final project into a single JAR containing all the deps; or to create a separate 'lib' directory of them: you will have to make some minor changes to the Maven project file ('pom.xml') to do this.
This Stackoverflow Post has an example of doing that.