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how to avoid using javac -cp

I have a Java class which uses a .jar file.
Every time that I want to compile this class, I have to do something like javac -cp ".:myJar.jar" myClass.java and every time that I want to execute it, I have to do the similar thing but with java instead of javac.
Is there a way to avoid doing this?
I know that I could put this jar file into my class path but I don't want to do that. I don't neither want to do a maven projet.

There is nothing preventing you from using an IDE, taking advantage of all its super useful features when developing the program, and then submit just the source code and associated jars to the professor.
Advantages of using IDE that your professor don't need:
Syntax color-coded editors with auto-complete.
Built-in display of javadoc, so you know what all the built-in Java methods do, and how they work.
Instant high-lighting of syntax errors.
Never having to compile the code, since IDE always keeps the code compiled.
Easy single-button execution of the program when you want to run it.
Debugger. Very important feature when your code is not working as you intended.
... more ...

library for Java/Groovy code analysis

I have a project that should analyze Java and Groovy code and build a special script from the source code.
Googling code analysis libraries didn't really result in anything useful for me.
But someone gave me a link to the Spoon project to analyze Java code.
Right now, the only parts that I need from Spoon are to give a set of .java files and it will return me the source code in a big data structure provided by Spoon.
So far the code that I use:
private CtPackage analyzeSourceCode()
{
Launcher spoon = new Launcher();
this.javaFiles.forEach(spoon::addInputResource);
spoon.buildModel();
return spoon.getFactory().Package().getRootPackage();
}
After which, I build up whatever I need from the packages returned.
(Note that I also require the actual executions, not only the data structures and members of the source code.)
But this only works for .java files and not for .groovy files... which brings me back to the point where I need a library to analyze Groovy code.
This one also doesn't allow me to use Java and Groovy together, so I need something else anyway.
Can anyone tell me what I am doing wrong in my google searches or provide me with links to a library that can analyze Java and Groovy code?

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.

Compiling a Java Project using Compiler API

I'm trying to compile a whole java project dynamically using the Compiler API. My initial thoughts of achieving this is to first know how to compile it in one-line using command line, then apply the same principle/parameters on the compiler object. Problem is, I never did, err, compiled using CLI. (Disadvantage of using an IDE? Haha)
So, am I on the right track? Moreover, can the project compilation achieved in one line execution? I'm having a hard time figuring this out because of the fact that it's a project, it contains packages galore.

So you either want to learn javac or Java Compiler API?
If you want CLI compilation look at javac (Linux | windows).
Alternatively for API, then programmatic use of Java's compiler API will definitely require more that one line, this will get you the compiler:
JavaCompilercompiler =ToolProvider.getSystemJavaCompiler();
Then you'll still need to load classes, write out byte code, and possibly package as a JAR.
You should use StandardJavaFileManager as you've probably many classes to manage, there's an example in the top of the JavaCompiler javadoc, but search for StandardJavaFileManager+JavaCompiler+example to find clearer examples like this blog post.

Dynamically generating java class from a java program

At the build(compile) time of my project I need to do code-generation for a java class. The generated java class is a java bean class with a set of getters and setters. At the build time I am getting the name of the class and names of variables. So what I need to do is dynamically generate the java bean from the information which I have.
eg. At the compile time I am getting following data.
class-name=Test
variable-name=aaa
So the generate class should look like following.
public class Test {
public String aaa;
public void setVar(String str) {
this.aaa = str;
}
public String getVar(){
return this.aaa;
}
}
When I searched for a tool that I can use, I found Arch4j [1] interesting but the problem with that is it is not compatible with Apache 2.0 license. I am looking for a project/tool that is compatible with Apache 2.0 license.
I would appreciate if someone can give me some insight on how I can do this.
[1] - http://arch4j.sourceforge.net/components/generator/index.html

Why not just generate the .java file during your build, using a custom ant task or Maven plugin? This seems like a rather easy task which doesn't need any complex library. You could even use a template file with placeholders for the class name and the field name, and generate the real .java file using a replace task.

JET from Eclipse can be used:
http://eclipse.org/articles/Article-JET/jet_tutorial1.html
It can be called by ant: http://help.eclipse.org/helios/index.jsp?topic=/org.eclipse.jet.doc/references/ant/antTasks.xhtml
And I think from maven: http://mvnrepository.com/artifact/org.eclipse/jet/0.8.0-v20070605

Take a look at javax.tools package. You can create and load a dynamically generated class only with that package.
Just bear in mind you need the JDK available and that's not re-distributable so your customer would need to downloaded it separately ( just like you do in any IDE today )
http://download.oracle.com/javase/6/docs/api/javax/tools/package-summary.html
For instance, you can invoke the java compiler programatically with:
http://download.oracle.com/javase/6/docs/api/javax/tools/JavaCompiler.html
And you can load it with URLClassLoader

Odd suggestion, but it seems like you want to generate beans. Why not use something like apache common's DynaBean? They allow you to create beans at run time. Here is an example of using DynaBean.
Of course this is at run time and not compile time. For compile time, I would recommend using an ant task to compile your source and add a dependency for compile on generation of your classes. You can handle the classes generation by writing a small java application that uses velocity as the java class template's engine.
So your ant task on compile first calls a small java program that generates the java class files using velocity template (delete the old files in ant if needed). Then compile as normal.