This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
The import statement is a little bit like the path statement in operating systems. It just makes stuff available, it doesn't do anything to bring it into your program. The import statement has a negligable (zero?)performance overhead. It is not, and I repeat NOT like the include statement in C/C++, and is entirely different to the extends statement.