Problems with ClassLoader and Jar-Files

1. I'm not good in englisch (writing).
2. I have the problem, that i want to load a object from an application in Jar-File A out of the Jar-File B. I set the CLASSPATH for B with System.setProperty("java.class.path", <ClassPath>); . Then i tried to get the Class-object from a class of B. I do it with getClass().getForName("package.Name");.
But everytime i get a ClassNotFoundException. Where is the Error? Or how can i load a class out of a Jar-File and get an instance? I hope you can help me..
Tobain

The error is that classes are loaded from the classpath as it existed when the program started. Changing the system property that was copied from the classpath has no effect, as you have seen. I have heard that you can write your own ClassLoader if you want to load classes from arbitrary locations, but I do not know how to do that myself.

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