I'm trying to throw an exception from a method, but when I compile the below code:

class launcher{
public static void main(String[] args){
    try{
        getError();
        System.out.println("Line: try block");
    }catch(myException e){
        System.out.println("Line: catch block");
    }finally{
        System.out.println("Line: finally block");
    }
    System.out.println("Line: EOF main");
}
static void getError() throws myException{
        throw new myException();
    }
}

I get the following compiler error:

launcher.java:14: error: cannot find symbol
    static void getError() throws ^myException{

  symbol:   class myException

  location: class launcher

It seems as if it can't understand what is myException?

Problem reason and solution

The problem is, that you haven't imported your Exception to the launcher class. Exceptions are classes so need to be declared as a typical class.

Huge problem

You start class names with lowercase letters which makes your class non-readable. Your classes should be called: Launcher (or better Test) and MyException instead of myException.

You can create your own Exceptions. The following is a declaration of MyException which you might find helpful:

MyException

public class MyException extends RuntimeException {
    public MyException() {
        super();
    }
}

Then import your new class and you'll be able to throw it.