java compile, directory confusion

[luftwaffe]

I think the answer to my question must be an obvious one and shorter than even the question I am a C++ programmer struggling with the first java program for a day or so. There is some code I have to port to java (not long, only a few classes but I have to keep the structure as must as possible). First I try to have two files compiled and running but could not achieve that for a day.

My current directory structure is like:
c:\MyProject\proj1.java\Api\_classes
c:\MyProject\proj1.java\Api\Api.java
c:\MyProject\proj1.java\Api\Test\Test.java

The files are like:
Api.java:

package Api;

public class Api {
}

Test.java:

package Api.Test;

import Api.*;

public class Test {
    public static void main(String[] args) {
        Api a = new Api();
        System.out.println("Hello, world");
    }
}

I actually created those with NetBeans and can compile/run. It needs to be integrated to the usual make process (now on Windows, later on linux). That should be no problem given that compilation of those will be successful (maybe .jar later, not that far yet).

So, how far I got:

C:\MyProject\proj1.java>javac -d C:\MyProject\proj1.java\_classes C:\MyProject\p
roj1.java\Api\Api.java

OK...

C:\MyProject\proj1.java>javac -d C:\MyProject\proj1.java\_classes C:\MyProject\p
roj1.java\Api\Test\Test.java

OK...

C:\MyProject\proj1.java>java -cp C:\MyProject\proj1.java\_classes C:\MyProject\p
roj1.java\_classes\Api\Test\Test
Caused by: java.lang.ClassNotFoundException: C:\MyProject\proj1.java\_classes\Ap
i\Test\Test
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
Could not find the main class: C:\MyProject\proj1.java\_classes\Api\Test\Test.
Program will exit.

FAIL...

Why?