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Create API jar like Android does with stubbed methods?

I'm looking to distribute a custom API and know the classes will be available at run time. I would like my public and protected methods / classes to be included in a jar I can distribute but I don't want any other source code and I would like to throw an exception if that jars code is actually executed.
This is the exact behaviour the Android framework jar has when you attempt to execute the jar directly.
My question is how to I create the same jar from my source without manually going through and creating each stubbed method. I would like this to scale as my API grows.

I believe you can use for that purpose the mkstubs tool: https://github.com/android/platform_development/tree/master/tools/mkstubs
As #CommonsWare mentioned stubs in AOSP are generated by javadoc DroidDoc script, read here: How are .java files in android_stubs_current_intermediates directory generated?

One possibility is to write a Java compiler which outputs a copy of your source code with empty method bodies or a body work a single statement which throws an exception. Then you can use normal dev tools to compile the generated classes.

Generate a Java class from Clojurescript using Rhino

I'd like to do the following: I have a simple function written in Clojure/ClojureScript:
(defn add
[a b]
(+ a b))
I want to wrap this function into a Java class and put it in a jar so that I can access it in an existing Java/Android project. My previous approach was to use gen-class and create an uberjar. This however leads to some problems.
As an alternative approach I considered compiling the function using ClojureScript (a solution also suggested by Sam Beran).
So far I understand how to:
compile javascript files into Java classes
put them in a .jar
Compile ClojureScript
I'm not struggling to get the ClojureScript output into a format that can be passed on to the Rhino compiler.
Any thoughts?
IMPORTANT NOTE: I do not want to create a class with a main function as is done here!

One general way of going about this would be to:
At build time:
run the ClojureScript compiler to generate a JavaScript file
put the JavaScript file into the resource directory.
compile the Java class that uses it
make a jar file (an Uberjar or a normal Unterjar)
this Java class should:
make a java class that on initialization start up Rhino
on instantiation runs the javascript from the resource.
On a desktop of server you may not get the same awesome startup times My. Beran reported on android because processes on android have the advantage of starting life with a warmed up runtime with Rhino ready to go from the moment they start (they inherit it from the Zygote process)

In Java, is there a logical reason why I cannot say "java MyClass.class " from command line?

Maybe this question may be splitting hairs, but when I compile a file from command line like :
javac MyClass.java
then afterward I cannot run it by saying
java MyClass.class
I have to call:
java MyClass
What is the motivation for this notation?

Because you run a class on the classpath, which may be contained inside a jar for example. You couldn't use your syntax in that case.

Java compiler needs a compilation unit; this is by default (at least) a java source file, with the whole of classes defined in it and its dependencies.
Java interpreter (the jvm) needs a single class with a main method as entry point of the execution - it must start somewhere.

You'd have to ask Sun (now Oracle) for the development history, but I do want to point out that for folks who are just using Java rather than developing Java, "java DoSomething" is easier to remember, and to type, than "java DoSomething.class"

There is no way to run a Java program that is not a class. For that reason, there is no reason to mandate typing the ".class". You might also invoke a class from within a JAR on your path, or directly, but it's still instantiating a class (possibly a "default" class from the Manifest).

Because the name of the class is MyClass and not MyClass.class. And when running java you specify the CLASS NAME and not the PATH to the actual compiled file.
For more in depth knowledge I guess Sun & Oracle will have to answer :)

Imagine that you have a class named package and you have a class named Class, in a package named package,
--CurrentFolder
--package
Class.class
package.class
so executing java package.class may lead to an undecidability to the compiler!

Issue running java program from batch file, runs fine in IDE

I'm doing some basic java homework for a class on my new laptop - issue is, I can't seem to get the program to compile and run from my batch file using the directions the instructor gave me.
I've set the Path variable to my JDK inside the Environment Variables settings.
My program is a simple shipping program to keep track of shipment information - I have the program working flawlessly in NetBeans (which our instructor advised us to use for developing the code), but he's going to be testing them using batch files, so we're also advised to test them on our systems with one we create prior to turning them in - pretty straightforward.
Issue is, I cannot seem to get this to work. I've never done it before, but I've used .bat files to compile and run C++ programs, as well as using makefiles on a unix system, so I feel like I'm absolutely stupid for not figuring this out on my own, but none of my searches have returned any fruitful solutions that help at all.
My program consists of 3 .java files:
Shipment.java - an interface that contains abstracted methods that are implemented in the ShipmentHW1 class
ShipmentHW1.java - a class that implements the abstracted methods from Shipment and has constructors, etc to create a usable object
TestShipment.java - the main class of this program, which utilizes and creates ShipmentHW1 objects based on preset parameters. This is super duper basic stuff here, and again, it runs perfectly fine inside the NetBeans IDE.
The instructions given to us state to have the batch file inside the package directory (which in this case I've set aside a seperate folder on my desktop titled "shipping", which is the package name - shouldn't be any issues there), where the 3 .java files are located as well.
They say if you don't need to explicitly list the path to the JDK, then you can simply have
javac TestShipment.java
java TestShipment.java
pause
Afterwards I get errors talking about how it "cannot find symbol Shipment s = new ShipmentHW1();"
I've tried adding imports, but since they're in the same package it shouldn't even be an issue.
Directory path is
C:\Users\X\Desktop\shipping
All 7 files are contained within:
TestShipment.java
TestShipment.class
Shipment.java
Shipment.class
ShipmentHW1.java
ShipmentHW1.class
doHW1.bat
Does anyone have any idea? I can provide more information if I've been too vague
Also, I'm on Windows 8 if that makes any difference

Solved
Batch file now reads
javac TestShipment.java Shipment.java ShipmentHW1.java
cd ..
java shipment.TestShipment
pause
and it works like a charm. Anyone have any ideas why I had to call the package.class instead of just compiling it regularly?

Try doing
javac TestShipment.java
java TestShipment
pause

Without seeing the contents of TestShipment.java, I'll assume you have some dependency on the Shipment and ShipmentHW1 classes. As such, when you execute a program that uses the TestShipment class, you need to have the .class files for each of the three (and any other dependencies).
So you will have to compile Shipment.java and ShipmentHW1.java as well before running your java command. If they are in the same package, you're good, if not, you will have to specify an appropriate value for the -cp option.
When running java with a class name, you need to specify the fully qualified class name.

If your .java files are declared to be in the 'shipping' package, then you probably need to be running java from the parent directory of 'shipping', e.g.
cd <path>/shipping
javac TestShipment.java
cd ..
java shipping/TestShipment

Accessing a Python object from Java Code in Jython 2.5

I have an application using Jython 2.1.
In the app I was using jythonc to convert the python scripts to java classes and then include these classes in my webapp like any other.
So I was able to assign package name to python scripts and access these classes like any other java class.
Now I plan to migrate to Jython 2.5. Jython 2.5 has removed support for jythonc.
So I tried to use
jython -m compileall /path/to/my/python/scripts.
When I do that I get all the compiled bytecode files in the same folder. Each of the files have names like myclass$py.class (where my python file is myclass.py).
My questions -
First of all can I access these classes in another normal java
class?
If so, what is the class name I should use ? When I use it like new
myclass() my code does not compile.
Is there a way, I can assign / force a package name or class name
for the generated bytecode with compileall?
Note -
I need to upgrade to jython 2.5 because I need newer versions of
python that it supports.
I would like to stick with pre-compiling the
python code into bytecode, as I want to do optimizations on the
bytecode. So the recommended object factory method is only a
last resort. I am assuming the object factory approach will not allow
me to process the generated bytecode.
Any help is appreciated.