结构型模式：Facade（外观）

http://zh.wikipedia.org/wiki/%E5%A4%96%E8%A7%80%E6%A8%A1%E5%BC%8F

/* Complex parts */
 
class CPU {
        public void freeze() { ... }
        public void jump(long position) { ... }
        public void execute() { ... }
}
 
class Memory {
        public void load(long position, byte[] data) {
                ...
        }
}
 
class HardDrive {
        public byte[] read(long lba, int size) {
                ...
        }
}
 
/* Façade */
 
class Computer {
        public void startComputer() {
                cpu.freeze();
                memory.load(BOOT_ADDRESS, hardDrive.read(BOOT_SECTOR, SECTOR_SIZE));
                cpu.jump(BOOT_ADDRESS);
                cpu.execute();
        }
}
 
/* Client */
 
class You {
        public static void main(String[] args) {
                Computer facade = new Computer();
                facade.startComputer();
        }
}