• 고객이 바라는 것을 제대로 수행하는 소프트웨어.
  
• 객체지향으로 만들어진 코드들. (코드의 유연성)
  
• OCP의 원리 이용. (코드의 재사용성)
  

import java.io.*;

class Guitar {
	private GuitarProperty GP;
	Guitar() {
		this.GP = null;
	}
	Guitar(GuitarProperty GP) {
		this.GP = GP;
	}
	public void setGP(GuitarProperty nGP){
		this.GP = nGP;
	}
	public GuitarPeroperty getGP() {
		return this.GP;
	}
}
class GuitarProperty {
	private String serialNumber;
	private double price;
	private String builder;
	private String model;
	private String type;
	private String backWood;
	private String topWood;
	public String getserialNumber(){
	}
	GuitarProperty() {
		this.serialNumber = null;
		this.price = 0;
		this.builder = null;
		this.model = null;
		this.type = null;
		this.backWood = null;
		this.topWood = null;
	}
	GuitarProperty(String SN, double price, String builder, String model, String type, 
		String backWood, String topWood) {
		this.serialNumber = SN;
		this.price = price;
		this.builder = builder;
		this.model = model;
		this.type = type;
		this.backWood = backWood;
		this.topWood = topWood;
	}
	public String getserialNumber() {return this.serialNumber; }
	public double getPrice() { return this.price; }
	public void setPrice(double newprice) { this.price = newprice; }
	public String getBuilder() { return this.builder; }
	public String getModel() { return this.model; }
	public String getType() { return this.type; }
	public String getBackWood() { return this.backWood; }
	public String getTopWood() { return this.topWood; }
}
class GuitarList {
	public Guitar Guitar;
	public GuitarList next;
	GuitarList() {
		this.Guitar = null;
		this.next = null;
}
class Inventory{
	private GuitarList GuitarList;
	private GuitarList GLPointer;
	public void addGuitar(GuitarProperty newGuitar) {
		this.GLPointer = this.GuitarList;
		while (this.GLPointer.next != null) {
			this.GLPointer = this.GLPointer.next;
		}
		this.GLPointer.next = new GuitarList();
		this.GLPointer.next.Guitar = new Guitar(newGuitar);
	}
	public Guitar getGuitar(String sn){
		this.GLPointer = this.GuitarList;
		while(this.GLPointer.Guitar != null && this.GLPointer.Guitar.getGP().getserialNumber() != sn && this.GLPointer.next != null) {
			this.GLPointer = this.GLPointer.next;
		}
		if (this.GLPointer.next == null && this.GLPointer.Guitar.getGP().getserialNumber() != sn) {
			return null;
		}
		else {
			return this.GLPointer.Guitar;
		}
	}
	public Guitar Search(GuitarProperty SGP) {
	}
}