Need help about jar file again!!

Question

I want to make some of my package used as library. And also put my application into executable jar file. I edited following codes:
uner path: D:\dd\b\b1
package b.b1;
public class Son
     int x = 10;
     public Son(){
     public int getX(){
          return x;
under path D:\b\b2
package b.b2;
import b.b1.Son;
public class Father
     public Father(){
     public static void main(String[] args)
          Son son = new Son();
          System.out.println("Hello World!"+son.getX());
Then I used jar tool make two jar files and also make one of then has specified main class Manifest.mf.
Here is my steps:
D:\bb>edit kk.txt
D:\bb>jar cmf kk.txt father.jar .\b\b2
D:\bb>jar cf son.jar .\b\b1
D:\bb>java -jar -classpath .;son.jar father.jar
Exception in thread "main" java.lang.NoClassDefFoundError: b/b1/Son
at b.b2.Father.main(Father.java:13)
I really do not know what's going on?
Interesting thing is I can get this result:
D:\bb>java -classpath .;son.jar b.b2.Father
Hello World!10
And if the father.jar does not depend on son.jar,
it is also works.
Thanks in advance.

Answer 1

I believe when you run with the -jar option, the classpath setting is ignore and you have to specify classpath in the manifest file.
From JDK Doc:
Class-Path :
The value of this attribute specifies the relative URLs of the extensions or libraries that this application or extension needs. URLs are separated by one or more spaces. The application or extension class loader uses the value of this attribute to construct its internal search path.
Sounds like you can specify a different path than the current directory, but you have to know beforehand what that path is.