I don't understand this answer? Here is the Q&A. What happens when you attempt to compile and run these two files in the same directory? //File P1.java package MyPackage; class P1{ void afancymethod(){ System.out.println("What a fancy method"); } } //File P2.java public class P2 extends P1{ afancymethod(); } 1) Both compile and P2 outputs "What a fancy method" when run 2) Neither will compile 3) Both compile but P2 has an error at run time 4) P1 compiles cleanly but P2 has an error at compile time Answer: 4) P1 compiles cleanly but P2 has an error at compile time Even though P2 is in the same directory as P1, because P1 was declared with the package statement it is not visible from P2
Actaully, it's quite simple. To use a package, you need to import it. If you add import MyPackage in P2.java, then it's fine. Remember, package != directory.
Don't get me started about those stupid light bulbs.