명품 자바 프로그래밍(개정4판) 제 5장 실습문제

1번.

class TV{
	private int size;
	public TV(int size) { this.size=size;}
	protected int getSize() { return size;}
}

class ColorTV extends TV{
	private int colorSize;
	public ColorTV(int size,int colorSize) {
		super(size);
		this.colorSize=colorSize;
	}
	public void printProperty() {
		System.out.println(getSize()+"인치 "+colorSize+"컬러");
	}
}

public class p0501 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		ColorTV myTV= new ColorTV(32,1024);
		myTV.printProperty();
	}

}

---

2번.

class TV{
	private int size;
	public TV(int size) { this.size=size;}
	protected int getSize() { return size;}
}

class ColorTV extends TV{
	private int colorSize;
	public ColorTV(int size,int colorSize) {
		super(size);
		this.colorSize=colorSize;
	}
	public void printProperty() {
		System.out.println(getSize()+"인치 "+colorSize+"컬러");
	}
}


class IPTV extends ColorTV{
	String ipAddress;
	
	public IPTV(String ip,int size,int colorSize) {
		super(size,colorSize);
		ipAddress=ip;
	}
	@Override
	public void printProperty() {
		System.out.print("나의 IPTV는 "+ipAddress+" 주소의 ");
		super.printProperty();
	}
}

public class p0502 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		IPTV iptv= new IPTV("192.1.1.2",32,2048);
		iptv.printProperty();
	}

}

---

3번.

import java.util.Scanner;

abstract class Converter{
	abstract protected double convert(double src);
	abstract protected String getSrcString();
	abstract protected String getDestString();
	protected  double ratio;
	
	public void run() {
		Scanner scanner = new Scanner(System.in);
		System.out.println(getSrcString()+"을 "+getDestString()+"로 바꿉니다.");
		System.out.print(getSrcString()+"을 입력하세요>> ");
		double val=scanner.nextDouble();
		double res=convert(val);
		System.out.println("변환 결과: "+res+getDestString()+"입니다.");
		scanner.close();
	}
}

class Won2Dollar extends Converter{
	public Won2Dollar(double ratio) {
		this.ratio=ratio;
	}
	protected double convert(double src) {
		return src/ratio;
	}
	
	protected String getSrcString() {
		return "원";
	}
	
	protected String getDestString() {
		return "달러";
	}
}

public class p0503 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Won2Dollar toDollar=new Won2Dollar(1200);
		toDollar.run();
	}

}

---

4번.

import java.util.Scanner;

abstract class Converter{
	abstract protected double convert(double src);
	abstract protected String getSrcString();
	abstract protected String getDestString();
	protected  double ratio;
	
	public void run() {
		Scanner scanner = new Scanner(System.in);
		System.out.println(getSrcString()+"을 "+getDestString()+"로 바꿉니다.");
		System.out.print(getSrcString()+"을 입력하세요>> ");
		double val=scanner.nextDouble();
		double res=convert(val);
		System.out.println("변환 결과: "+res+getDestString()+"입니다.");
		scanner.close();
	}
}

class Km2Mile extends Converter{
	
	public Km2Mile(double ratio) {
		this.ratio=ratio;
	}
	protected double convert(double src) {
		return src/ratio;
	}
	
	protected String getSrcString() {
		return "Km";
	}
	
	protected String getDestString() {
		return "mile";
	}
}

public class p0504 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Km2Mile toMile=new Km2Mile(1.6);
		toMile.run();
	}

}

---

5번.

class Point{
	private int x,y;
	public Point(int x,int y) {this.x=x;this.y=y;}
	public int getX() {return x;}
	public int getY() {return y;}
	protected void move(int x,int y) {
		this.x=x;
		this.y=y;
	}
}

class ColorPoint extends Point{
	String color;
	public ColorPoint(int x,int y,String color) {
		super(x,y);
		this.color=color;
	}
	public void setXY(int x,int y) {
		move(x,y);
	}
	public void setColor(String color) {
		this.color=color;
	}
	public String toString() {
		return color+"색의 ("+getX()+","+getY()+")의 점";
	}
}

public class p0505 {
	public static void main(String[] args) {
		ColorPoint cp=new ColorPoint(5, 5, "YELLOW");
		cp.setXY(10, 20);
		cp.setColor("RED");
		String str=cp.toString();
		System.out.println(str+"입니다.");
	}
}

---

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6번.

class Point{
	private int x,y;
	public Point(int x,int y) {this.x=x;this.y=y;}
	public int getX() {return x;}
	public int getY() {return y;}
	protected void move(int x,int y) {
		this.x=x;
		this.y=y;
	}
}

class ColorPoint extends Point{
	String color;
	public ColorPoint() {
		super(0,0);
		color="BLACK";
	}
	public ColorPoint(int x,int y) {
		super(x,y);
		color="BLACK";
	}
	public ColorPoint(int x,int y,String color) {
		super(x,y);
		this.color=color;
	}
	public void setXY(int x,int y) {
		move(x,y);
	}
	public void setColor(String color) {
		this.color=color;
	}
	public String toString() {
		return color+"색의 ("+getX()+","+getY()+")의 점";
	}
}


public class p0506 {
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		ColorPoint zeroPoint = new ColorPoint();
		System.out.println(zeroPoint.toString()+"입니다.");
		
		ColorPoint cp=new ColorPoint(10,10);
		cp.setXY(5, 5);
		cp.setColor("RED");
		System.out.println(cp.toString()+"입니다.");
	}
}

---

7번.

class Point{
	private int x,y;
	public Point(int x,int y) {this.x=x;this.y=y;}
	public int getX() {return x;}
	public int getY() {return y;}
	protected void move(int x,int y) {
		this.x=x;
		this.y=y;
	}
}

class Point3D extends Point{
	int z;
	public Point3D(int x,int y,int z) {
		super(x,y);
		this.z=z;
	}
	public void moveUp() {
		z++;
	}
	public void moveDown() {
		z--;
	}
	public String toString() {
		return "("+getX()+","+getY()+","+z+")의 점";
	}
	public void move(int x,int y,int z) {
		super.move(x, y);
		this.z=z;
	}
}

public class p0507 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Point3D p=new Point3D(1, 2, 3);
		System.out.println(p.toString()+"입니다.");
		
		p.moveUp();
		System.out.println(p.toString()+"입니다.");
		
		p.moveDown();
		p.move(10, 10);
		System.out.println(p.toString()+"입니다.");
		
		p.move(100,200,300);
		System.out.println(p.toString()+"입니다.");
		
	}

}

---

8번.

class Point{
	private int x,y;
	public Point(int x,int y) {this.x=x;this.y=y;}
	public int getX() {return x;}
	public int getY() {return y;}
	protected void move(int x,int y) {
		this.x=x;
		this.y=y;
	}
}

class PositivePoint extends Point{
	public PositivePoint() {
		super(0,0);
	}
	public PositivePoint(int x,int y) {
		super(x,y);
		if(getX()<0||getY()<0) {
			move(0,0);
		}
	}
	public String toString() {
		return "("+getX()+","+getY()+")"+"의 점";
	}
	protected void move(int x1,int y1) {
		if(x1<0||y1<0) {
			return;
		}
		else {
			super.move(x1, y1);
		}
	}
}

public class p0508 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		PositivePoint p=new PositivePoint();
		p.move(10, 10);
		System.out.println(p.toString()+"입니다.");
		
		p.move(-5, 5);
		System.out.println(p.toString()+"입니다.");
		
		PositivePoint p2=new PositivePoint(-10,-10);
		System.out.println(p2.toString()+"입니다.");
	}

}

---

9번.

import java.util.Scanner;

interface Stack{
	int length();
	int capacity();
	String pop();
	boolean push(String val);
}

class StringStack implements Stack{
	String[] arr;
	int len,cap;
	public StringStack(int n) {
		arr=new String[n];
		len=0;
		cap=n;
	}
	
	public int length() {
		return len;
	}
	
	public int capacity() {
		return cap;
	}
	
	public String pop() {
		return arr[--len];
	}
	
	public boolean push(String val) {
		if(len==cap) {
			System.out.println("스택이 꽉 차서 푸시 불가!");
			return false;
		}
		else {
			arr[len++]=val;
			return true;
		}
	}	
	
	public boolean isEmpty() {
		if(len==0) {
			return true;
		}
		else {
			return false;
		}
	}
	
	public void print() {
		System.out.print("스택에 저장된 모든 문자열 팝 :");
		while(!isEmpty()) {
			System.out.print(" "+pop());
		}
		System.out.println();
	}
}

public class p0509 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc=new Scanner(System.in);
		System.out.print("총 스택 저장 공간의 크기 입력 >>");
		
		int n=sc.nextInt();
		StringStack ss=new StringStack(n);
		
		String op;
		while(true) {
			System.out.print("문자열 입력 >> ");
			op=sc.next();
			if(op.equals("그만")) {
				break;
			}
			ss.push(op);
		}
		ss.print();
	}

}

---

10번.

abstract class PairMap{
	protected String keyArray[];
	protected String valueArray[];
	abstract String get(String key);
	abstract void put(String key,String value);
	abstract String delete(String key);
	abstract int length();
}

class Dictionary extends PairMap{
	private int num;
	//생성자로 배열을 초기화
	public Dictionary(int n) {
		num=0;
		keyArray=new String[n];
		valueArray=new String[n];
	}
	
	String get(String key) {
		for(int i=0;i<num;i++) {
			//입력된 키값과 같은게 있으면 리턴
			if(keyArray[i].equals(key)){
				return valueArray[i];
			}
		}
		return null;
	}
	
	void put(String key,String value) {
		for(int i=0;i<num;i++) {
			//만약에 키값이 같은게 있으면 벨류값 수정
			if(keyArray[i].equals(key)) {
				valueArray[i]=value;
				return;
			}
		}
		//아니면 추가
		valueArray[num]=value;
		keyArray[num++]=key;
		return;
	}
	String delete(String key) {
		String deleteData=null;
		for(int i=0;i<num;i++) {
			//삭제하려는 키값이 존재하면 저장 후 삭제
			if(keyArray[i].equals(key)){
				deleteData=valueArray[i];
				for(int j=i;j<num-1;j++) {
					valueArray[j]=valueArray[j+1];
					keyArray[j]=keyArray[j+1];
				}
				num--;
			}
		}
		//저장한 값을 반환
		return deleteData;
	}
	int length() {
		return num;
	}
}

public class p0510 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Dictionary dic=new Dictionary(10);
		dic.put("황기태","자바");
		dic.put("이재문","파이선");
		dic.put("이재문", "C++");
		System.out.println("이재문의 값은 "+dic.get("이재문"));
		System.out.println("황기태의 값은 "+dic.get("황기태"));
		dic.delete("황기태");
		System.out.println("황기태의 값은 "+dic.get("황기태"));
	}

}

---

11번.

import java.util.Scanner;

abstract class Calc{
	int a,b;
	abstract void setValue(int a,int b);
	abstract int calculate();
}

class Add extends Calc{
	void setValue(int a,int b) {
		this.a=a;
		this.b=b;
	}
	
	int calculate() {
		return a+b;
	}
}

class Sub extends Calc{
	void setValue(int a,int b) {
		this.a=a;
		this.b=b;
	}
	
	int calculate() {
		return a-b;
	}
}

class Mul extends Calc{
	void setValue(int a,int b) {
		this.a=a;
		this.b=b;
	}
	
	int calculate() {
		return a*b;
	}
}

class Div extends Calc{
	void setValue(int a,int b) {
		this.a=a;
		this.b=b;
	}
	
	int calculate() {
		if(b==0) {
			System.out.println("0으로 나눌 수 없어요");
		}
		else {
			System.out.println(a/b);
		}
	}
}

public class p0511 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc=new Scanner(System.in);
		System.out.print("두 정수와 연산자를 입력하시오>>");
		int a=sc.nextInt();
		int b=sc.nextInt();
		String op=sc.next();
		Calc sp;
		switch(op.charAt(0)) {
		case '+':
			sp=new Add();
			break;
		case '-':
			sp=new Sub();
			break;
		case '*':
			sp=new Mul();
			break;
		case '/':
			sp=new Div();
			break;
		default:
			return ;
		}
		sp.setValue(a, b);
		System.out.println(sp.calculate());
	}

}

---

12번.

import java.util.Scanner;

abstract class Shape{
	private Shape next;
	public Shape() {
		next=null;
	}
	public void setNext(Shape obj) {
		next=obj;
	}
	public Shape getNext() {
		return next;
	}
	public abstract void draw();
}

class Line extends Shape{
	public Line() {
		super();
	}
	//오버라이딩
	public void draw() {
		System.out.println("Line");
	}
}

class Rect extends Shape{
	public Rect() {
		super();
	}
	//오버라이딩
	public void draw() {
		System.out.println("Rect");
	}
}

class Circle extends Shape{
	public Circle() {
		super();
	}
	//오버라이딩
	public void draw() {
		System.out.println("Circle");
	}
}

class GraphicEditor{
	private Shape head,tail;
	private Scanner sc;
	
	//기본생성자
	public GraphicEditor(){
		head=null;
		tail=null;
		sc=new Scanner(System.in);
	}
	
	//에디터 실행 메서드
	void runEditor() {
		int choice;
		System.out.println("그래픽 에디터 beauty을 실행합니다.");
		
		do {
		System.out.print("삽입(1), 삭제(2), 모두 보기(3), 종료(4)>>");
		choice=sc.nextInt();
			switch(choice) {
			case 1:
				System.out.print("Line(1), Rect(2), Circle(3)>>");
				int option=sc.nextInt();
				put(option);
				break;
			case 2:
				System.out.print("삭제할 도형의 위치>>");
				int index=sc.nextInt();
				delete(index);
				break;
			case 3:
				print();
				break;
			case 4:
				break;
			default:
				System.out.println("다시 입력해주세요");
				break;
			}
		}while(choice!=4);
		System.out.println("beauty을 종료합니다.");
	}
	
	//리스트에 넣는 메서드
	void put(int num) {
		Shape g;
		//입력번호에 따라 Line,Rect,Circle객체 생성
		switch(num) {
		case 1:
			g=new Line();
			break;
		case 2:
			g=new Rect();
			break;
		case 3:
			g=new Circle();
			break;
		default:
			System.out.println("다시입력해주세요");
			return;
		}
		//리스트에 연결
		if(head==null) {
			head=g;
			tail=g;
		}
		else {
			tail.setNext(g);
			tail=g;
		}
		return;
	}
	void delete(int index) {
		Shape cur=head;
		Shape temp=head;
		if(head==null) {
			System.out.println("삭제할 수 없습니다.");
			return;
		}
		//리스트에서 해당 인덱스의 노드 삭제
		if(index==1) {
			if(head==tail) {
				tail=head=null;
				return;
			}
			else {
				head=head.getNext();
				return;
			}
		}
		else {
			int i;
			for(i=1;i<index;i++) {
				temp=cur;
				cur=cur.getNext();
				if(cur==null) {
					System.out.println("삭제할 수 없습니다.");
					return;
				}
			}
			if(cur==tail) {
				tail=temp;
				tail.setNext(null);
			}
			else {
				temp.setNext(cur.getNext());
			}
		}
	}
	
	void print() {
		Shape d=head;
		while(d!=null) {
			d.draw();
			d=d.getNext();
		}
	}
}

public class p0512 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		GraphicEditor ge=new GraphicEditor();
		ge.runEditor();
	}

}

---

13번.

interface Shape{
	final double PI=3.14;
	void draw();
	double getArea();
	default public void redraw() {
		System.out.print("--- 다시 그립니다. ");
		draw();
	}
}

class Circle implements Shape{
	int r;
	public Circle(int r) {
		this.r=r;
	}
	public void draw() {
		System.out.println("반지름이 "+r+"인 원 입니다.");
	}
	public double getArea() {
		return r*r*PI;
	}
}

public class p0513 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Shape donut=new Circle(10);
		donut.redraw();
		System.out.println("면적은 "+donut.getArea());
	}

}

---

14번.

interface Shape{
	final double PI=3.14;
	void draw();
	double getArea();
	default public void redraw() {
		System.out.print("--- 다시 그립니다. ");
		draw();
	}
}

class Circle implements Shape{
	int r;
	public Circle(int r) {
		this.r=r;
	}
	public void draw() {
		System.out.println("반지름이 "+r+"인 원 입니다.");
	}
	public double getArea() {
		return r*r*PI;
	}
}

class Oval implements Shape{
	int x,y;
	public Oval(int x,int y) {
		this.x=x;
		this.y=y;
	}
	public double getArea() {
		return x*y*PI; 
	}
	public void draw() {
		System.out.println(x+"x"+y+"에 내접하는 타원입니다.");
	}
}

class Rect implements Shape{
	int x,y;
	public Rect(int x,int y) {
		this.x=x;
		this.y=y;
	}
	public double getArea() {
		return x*y;
	}
	public void draw() {
		System.out.println(x+"x"+y+"크기의 사각형 입니다.");
	}
}

public class p0514 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Shape [] list= new Shape[3];
		list[0] = new Circle(10);
		list[1]=new Oval(20,30);
		list[2]=new Rect(10,40);
		for(int i=0;i<list.length;i++) list[i].redraw();
		for(int i=0;i<list.length;i++) System.out.println("면적은 "+list[i].getArea());
	}	

}