public class CPU 
{
    public static final Logger LOGGER = Logger.getLogger(CPU.class);
    public void start()
    {
        LOGGER.info("cpu is start...");
    }
    
    public void shutDown()
    {
        LOGGER.info("CPU is shutDown...");
    }
}

public class Disk
{
    public static final Logger LOGGER = Logger.getLogger(Disk.class);
    public void start()
    {
        LOGGER.info("Disk is start...");
    }
    
    public void shutDown()
    {
        LOGGER.info("Disk is shutDown...");
    }
}

public class Memory
{
    public static final Logger LOGGER = Logger.getLogger(Memory.class);
    public void start()
    {
        LOGGER.info("Memory is start...");
    }
    
    public void shutDown()
    {
        LOGGER.info("Memory is shutDown...");
    }
}

public class Computer
{
    public static final Logger LOGGER = Logger.getLogger(Computer.class);
    
    private CPU cpu;
    private Memory memory;
    private Disk disk;
    public Computer()
    {
        cpu = new CPU();
        memory = new Memory();
        disk = new Disk();
    }
    public void start()
    {
        LOGGER.info("Computer start begin");
        cpu.start();
        disk.start();
        memory.start();
        LOGGER.info("Computer start end");
    }
    
    public void shutDown()
    {
        LOGGER.info("Computer shutDown begin");
        cpu.shutDown();
        disk.shutDown();
        memory.shutDown();
        LOGGER.info("Computer shutDown end...");
    }
}

public class Cilent {
    public static final Logger LOGGER = Logger.getLogger(Cilent.class);
    public static void main(String[] args) 
    {
        Computer computer = new Computer();
        computer.start();
        LOGGER.info("=================");
        computer.shutDown();
    }

}