//1. 함수 -> 메소드
// 자동완성 ctrl + space
// 컴파일 ctrl + F11
// 자동 정렬 ctrl + shift + f
/*
import java.util.*;
public class Main { //메인 클래스
public static void main(String[] args) {
// 자료형
int a=10;
long b; //long long int 아님 주의!1
float c;
double d;
char e; //문자
String f="love";//문자열
//출력 syso + ctrl +space
//System.out.println("hello");
//System.out.println("hello "+a);
//입력 Scanner 객체 생성
Scanner sc = new Scanner(System.in);
int x = sc.nextInt();
System.out.println(x);
float y = sc.nextFloat();
System.out.println(y);
String s = sc.next();
System.out.println(s);
String t = sc.nextLine(); // 한 줄
}
}
*/
/*
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a=sc.nextInt();
System.out.println(a);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
float a=sc.nextFloat();
System.out.printf("%.6f",a);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int a=sc.nextInt();
System.out.print(a+" "+a+" "+a);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
float a=sc.nextFloat();
float b=sc.nextFloat();
System.out.printf("%.2f",a*b);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int a=sc.nextInt();
int b=sc.nextInt();
System.out.printf("%.1f",a*b/2.0);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int a=sc.nextInt();
if(50<=a&&a<=70||a%6==0){
System.out.println("win");
}
else{
System.out.println("lose");
}
}
}
*/
/*
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
int b = sc.nextInt();
if (b >= 30) {
b -= 30;
}
else if (a != 0) {
a--;
b += 30;
}
else {
a = 23;
b += 30;
}
System.out.println(a + " " + b);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int a=sc.nextInt();
int b=sc.nextInt();
int c=sc.nextInt();
if(170<a&&170<b&&170<c) {
System.out.println("PASS");
}
else if(170>=a){
System.out.println("CRASH "+a);
}
else if(170>=b){
System.out.println("CRASH "+b);
}
else{
System.out.println("CRASH "+c);
}
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int a=sc.nextInt();
int b=sc.nextInt();
int c=sc.nextInt();
int n=sc.nextInt();
for(int i=1;i<n;i++) {
a=a*b+c;
}
System.out.println(a);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int a=sc.nextInt();
int b=sc.nextInt();
for(int i=a;i<=b;i++)
{
for(int j=1;j<=9;j++)
{
System.out.printf("%d*%d=%d\n",i,j,i*j);
}
}
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int n=sc.nextInt();
for(int i=n-1;i>=0;i--)
{
for(int j=1;j<=i;j++)
{
System.out.print(" ");
}
for(int j=1;j<=n;j++)
{
System.out.print("*");
}
System.out.println();
}
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int n=sc.nextInt();
for(int i=n-1;i>=0;i--)
{
for(int j=1;j<=i;j++)
{
System.out.print(" ");
}
for(int j=1;j<=n;j++)
{
System.out.print("*");
}
System.out.println();
}
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int n = sc.nextInt();
int arr[] = new int[n];
for(int i=0;i<n;i++){
arr[i]=sc.nextInt();
}
for(int i=0;i<n;i++){
for(int j=i;j<n;j++){
System.out.print(arr[j]+" ");
}
for(int j=0;j<=i-1;j++) {
System.out.print(arr[j]+" ");
}
System.out.println();
}
}
}
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int arr[]=new int[10];
for(int i=0;i<10;i++) {
arr[i]=sc.nextInt();
}
int k=sc.nextInt();
System.out.println(arr[k-1]);
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
String str = sc.nextLine();
for(int i=0;i<str.length();i++) {
System.out.print(str.charAt(i)+" ");
}
}
}
*/
/*
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
String str=sc.next();
for(int i=0;i<str.length();i++) {
System.out.println("'"+str.charAt(i)+"'");
}
}
}
*/
/*
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String s1 = sc.next();
String s2 = sc.next();
String s3 = sc.next();
if (s1.charAt(s1.length() - 1) == s2.charAt(0)&&s2.charAt(s2.length() - 1) == s3.charAt(0)&&s3.charAt(s3.length() - 1) == s1.charAt(0))
{
System.out.println("good");
}
else {
System.out.println("bad");
}
}
}
클래스 : 틀
필드 + 메소드(함수) + 생성자
객체 : 클래스로 찍어낸 것 들..
import java.util.*;
class Person{
//field 필드
int age;
String name;
//메소드
void speak() {
System.out.println(age+" ,hi im "+name+"...");
}
void sleep() {
}
}
public class Main{
public static void main(String[] args) {
Person a = new Person(); //a 객체 생성
Person b = new Person();
a.age=10;
a.name="james";
a.speak();
b.age=30;
b.name = "Mark";
b.speak();
}
}
*/
/*
import java.util.*;
class Circle{
int radius;
String name;
//생성자 - 객체를 생성할때, 필드의 초깃값 설정
public Circle(int radius) {
this.radius=radius;
}
public Circle(int radius, String name) {
this.radius=radius;
this.name=name;
}
public double getArea() {
return 3.14*radius*radius;
}
}
public class Main{
public static void main(String[] args) {
Circle pizza=new Circle(10,"A");
double area =pizza.getArea();
System.out.println(pizza.name+"의 면적은"+area);
Circle donut=new Circle(2);
// donut.radius=2;
// donut.name="B";
// area=donut.getArea();
// System.out.println(donut.name+"의 면적은"+area);
}
}
*/
/*
class Circle {
int radius;
String name;
public Circle() {
radius = 1;
name = "";
}
public Circle(int r, String n) {
radius = r;
name = n;
}
public double getArea() {
return 3.14 * radius * radius;
}
}
class Main {
public static void main(String[] args) {
Circle pizza = new Circle(10, "A");
double area = pizza.getArea();
System.out.println(pizza.name + "의 면적은" + area);
}
}
*/
/*
import java.util.*;
class Song {
String title;
public Song(String title) {
this.title=title;
}
public String gettitle() {
return title;
}
}
public class Main{
public static void main(String[] args) {
Song mysong=new Song("Nessun Dorma");
Song yoursong= new Song("공주는 잠 못 이루고");
System.out.println("네 노래는 "+ mysong.gettitle());
System.out.println("너 노래는 "+yoursong.gettitle());
}
}
접근지정자
public 다른 모든 클래스에서 접근 가능
private 그 클래스 내부에서만 접근 가능
*/
/*
import java.util.*;
class Phone {
private String tel, name;
public Phone(String tel, String name) {
this.tel = tel;
this.name = name;
}
public String getName(){
return name;
}
public String getTel() {
return tel;
}
}
public class Main {
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int arr[50]; (X)
int arr[] = new int [50]; //(o)
//객체배열생성시 두번 해야한다
Phone parr[] = new Phone[50]; //레퍼런스변수 생성
for(int i=0; i<parr.length; i++) {
String name = sc.next();
String tel =sc.next();
parr[i] = new Phone(tel,name); //객체생성
}
System.out.print("이름과 전화번호 입력 >>");
String name = sc.next();
String tel =sc.next();
Phone mytel = new Phone(tel,name);
System.out.println("이름과 전화번호 입력 >>");
String name1=sc.next();
String tel1=sc.next();
Phone yourtel=new Phone(tel1,name1);
System.out.println(mytel.name+"의 번호"+mytel.tel);
System.out.println(mytel.getName()+"의 번호"+mytel.getTel());
System.out.println(yourtel.getName()+"의 번호"+yourtel.getTel());
}
}
*/
/*
import java.util.*;
class Book{
String title,author;
public Book(String title,String author) {
this.title=title;
this.author=author;
}
}
public class Main{
public static void main(String[] args) {
Book[]book=new Book[2];
Scanner sc=new Scanner(System.in);
for(int i=0;i<book.length;i++) {
System.out.println("제목>>");
String title=sc.nextLine();
System.out.print("저자>>");
String author=sc.nextLine();
book[i]=new Book(title,author);
}
}
}
*/
/*
import java.util.*;
class Rect{
private int width,height;
public Rect(int width,int height) {
this.width=width;
this.height=height;
}
public int getArea() {return width*height;}
}
public class Main{
public static void main(String[] args) {
Rect[]rect= new Rect[4];
Scanner sc=new Scanner(System.in);
for(int i=0;i<rect.length;i++) {
System.out.print(i+1);
System.out.print(" 너비와 높이 >>");
int width=sc.nextInt();
int height=sc.nextInt();
rect[i] = new Rect(width,height);
}
int sum=0;
for(int i=0;i<rect.length;i++) {
sum=sum+rect[i].getArea();
}
System.out.print("저장하였습니다...");
System.out.println("사각형의 전체 합은 "+sum);
}
}
*/
/*
import java.util.*;
class Phone {
private String name, tel;
public Phone(String name, String tel) {
this.name = name;
this.tel = tel;
}
public String getname() {return name;}
public String gettel() {return tel;}
}
public class Main {
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
//1.
System.out.print("인원수>>");
int n = sc.nextInt();
Phone[] phone= new Phone[n];
//2.
for(int i=0;i<phone.length;i++) {
System.out.print("이름과 전화번호(번호는 연속적으로 입력)>>");
String name=sc.next();
String tel=sc.next();
phone[i]=new Phone(name,tel);
}
System.out.println("저장되었습니다...");
//3.
while(true) {
System.out.print("검색할이름>>");
String name = sc.next();
int flag=0;
for(int i=0;i<phone.length;i++)
{
if(name.equals(phone[i].getname()))
{
flag=1;
System.out.println(name+" 의 번호는 " +phone[i].gettel()+" 입니다.");
break;
}
}
if(flag==0)
{
System.out.println(name+" 이 없습니다.");
}
if(name.equals("exit")) break;
}
System.out.println("프로그램을 종료합니다...");
}
}
*/
/*
import java.util.*;
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{
private String color;
public ColorPoint(int x,int y,String color) {
super(x,y);
this.color=color;
}
public void setPoint(int x,int y){
move(x,y);
}
public void setColor(String color) {
this.color=color;
}
public void show() {
System.out.println(color+"색으로"+"("+getX()+","+getY()+")");
}
}
class Main{
public static void main(String[] args) {
ColorPoint cp=new ColorPoint(5,5,"YELLOW"); //ColorPoint 객체 생성
cp.setPoint(10, 20);
cp.setColor("GREEN");
cp.show();
}
}
class
abstract class 추상클래스 (일부만 작성된 클래스)
interface 인터페이스 (틀만 있는 클래스)
import java.util.*;
interface StackInterface {
int length(); //추상메소드 (내용이 작성이 안된 메소드)
String pop();
boolean push(String ob);
}
class StringStack implements StackInterface {
private int top=-1; //top이 마지막 데이터의 위치
String stack[] = new String[5];
//추상메소드들 구현
public int length() {
return top+1;
}
public String pop() {
return stack[top--];
}
public boolean push(String ob) {
if(top!=4){
top++;
stack[top]=ob;
return true;
}
else return false;
}
}
class Main {
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
StringStack cp=new StringStack();
for(int i=0;i<5;i++) {
String str = sc.next();
cp.push(str);
}
for(int i=0;i<5;i++) {
System.out.print(cp.pop()+" ");
}
}
}
import java.util.*;
interface Shape {
final double PI=3.14;
void draw();
double getArea();
default public void redraw() {
System.out.println("--- 다시 그립니다. ---");
draw();
}
}
class Circle implements Shape {
private int radius;
public Circle (int radius) {
this.radius=radius;
}
public void draw() {
System.out.print("반지름 "+radius);
}
public double getArea() {
return radius*radius*PI;
}
}
public class Main {
public static void main(String[] args) {
Shape coin=new Circle(10);
coin.redraw();
System.out.print(" 코인의 면적은"+coin.getArea());
}
GUI
GRAPHIC USER INTERFACE
그래픽으로 컴퓨터랑 소통하기
컴포넌트 - Button, TextField, JLabel
컨테이너 - Frame, Panel,
contain(포함하다) +er
import java.awt.*;
import javax.swing.*;
public class Main extends JFrame {
public Main() {
//기본 셋팅
setSize(1000,300);
setVisible(true);
//프레임 이름지어주기
Container c = getContentPane();
c.setBackground(Color.yellow); // 배경색 설정
//layout 레이아웃 : 배치관리자
c.setLayout(new FlowLayout());
//컨테이너에 컴포넌트 추가 방법1
JButton b1 = new JButton("예준1");
b1.setBackground(Color.green); //버튼의 배경색 설정
b1.setForeground(Color.white); //버튼의 글자색 설정
c.add(b1);
//컨테이너에 컴포넌트 추가 방법2
c.add(new JButton("예준2"));
JLabel la = new JLabel("라벨입니다");
c.add(la);
}
public static void main(String[] args) {
Main frame=new Main();
}
}
문제 1
가로 500픽셀 세로 300픽셀
컨테이너 배경색은 white
라벨, 버튼, 버튼
라벨 "label" 글자색은 red
버튼 "버튼1" 배경색은 green 글자색 white
버튼 "버튼2" 배경색은 blue 글자색 white
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
public Main() {
setSize(300,500);
setVisible(true);
Container c=getContentPane();
c.setLayout(new FlowLayout());
c.setBackground(Color.white);
JLabel la=new JLabel("label");
la.setForeground(Color.red);
c.add(la);
JButton b1=new JButton("버튼1");
b1.setBackground(Color.green);
b1.setForeground(Color.white);
c.add(b1);
JButton b2=new JButton("버튼2");
b2.setBackground(Color.blue);
b2.setForeground(Color.white);
c.add(b2);
}
public static void main(String[] args) {
Main frame=new Main();
}
}
c.setLayout(null);
c.setBackground(Color.white);
JLabel la=new JLabel("label-0");
la.setForeground(Color.red);
la.setSize(50,50);
la.setLocation(100,50);
c.add(la);
layout(배치관리자)
1. flowlayout : 그냥 적당히 알아서 순서대로 위치, 사이즈 지정 (내가 위치와 사이즈를 정할 수 없다)
2. null : 배치관리자가 아예 없다. 꼭 사이즈와 위치를 지정해주어야 한다.
3. gridlayout : 이차원배열 형태로 순서대로 집어넣어준다 (내가 위치와 사이즈를 정할 수 없다)
4. BorderLayout : 동서남북중앙
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
public Main() {
setSize(500,300);
setVisible(true);
Container c=getContentPane();
c.setLayout(new BorderLayout());
JPanel p1 = new JPanel();
p1.setBackground(Color.red);
c.add(p1,BorderLayout.CENTER);
p1.setLayout(null);
JButton b1 = new JButton("center button");
b1.setSize(200, 100);
b1.setLocation(100, 100);
p1.add(b1);
JPanel p2 = new JPanel();
p2.setBackground(Color.white);
c.add(p2,BorderLayout.NORTH);
p2.add(new JButton("north button"));
p2.add(new JButton("north button"));
// JButton b1 = new JButton("button1");
// c.add(b1,BorderLayout.EAST);
// JButton b2 = new JButton("button2");
// c.add(b2,BorderLayout.CENTER);
// JButton b3 = new JButton("button3");
// c.add(b3,BorderLayout.WEST);
// for(int i=0;i<6;i++) {
// JButton b = new JButton("button"+i);
// c.add(b);
// }
}
public static void main(String[] args) {
Main frame=new Main();
}
}
*/
/*
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
public Main() {
setSize(400,400);
setVisible(true);
Container c=getContentPane();
c.setLayout(new BorderLayout(7,5));
JButton b1=new JButton("North");
c.add(b1,BorderLayout.NORTH);
JButton b2=new JButton("West");
c.add(b2,BorderLayout.WEST);
JButton b5=new JButton("Center");
c.add(b5,BorderLayout.CENTER);
JButton b3=new JButton("South");
c.add(b3,BorderLayout.SOUTH);
JButton b4=new JButton("East");
c.add(b4,BorderLayout.EAST);
}
public static void main(String[] args) {
Main frame=new Main();
}
}
*/
/*
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
public Main() {
setSize(800,400);
setVisible(true);
Container c=getContentPane();
c.setLayout(new GridLayout(1,10));
for(int i=0;i<10;i++) {
String si = Integer.toString(i);
//정수를 문자열로 변환할때 쓰임!!! 꼭 기억하기!!!
JButton b=new JButton(si);
c.add(b);
}
}
public static void main(String[] args) {
Main frame=new Main();
}
}*/
//527p
/*
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
public Main() {
setSize(500,600);
setVisible(true);
Container c=getContentPane();
c.setLayout(new BorderLayout());
JPanel p1=new JPanel();
p1.setBackground(Color.gray);
c.add(p1,BorderLayout.NORTH);
JPanel p2=new JPanel();
p2.setBackground(Color.lightGray);
c.add(p2,BorderLayout.CENTER);
}
public static void main(String[] args) {
Main frame=new Main();
}
}
*/
/*
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Main extends JFrame {
public Main() {
setSize(470,200);
setVisible(true);
}
public static void main(String[] args) {
Main frame=new Main();
}
}
*/
/*
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Main extends JFrame {
private JLabel la1=new JLabel("0");
private JLabel la2=new JLabel("0");
private JLabel la3=new JLabel("0");
private JLabel la4=new JLabel("시작합니다.");
public Main() {
setTitle("Open Challenge 10");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container c=getContentPane();
c.addKeyListener(new MyKeyListener());
c.setLayout(null);
c.add(la1);
c.add(la2);
c.add(la3);
c.add(la4);
la1.setBackground(Color.MAGENTA);
la1.setSize(100,40);
la1.setLocation(100,50);
la1.setOpaque(true);
la1.setHorizontalAlignment(JLabel.CENTER);
la1.setForeground(Color.YELLOW);
la1.setFont(new Font("Arial",Font.ITALIC, 40));
la2.setBackground(Color.MAGENTA);
la2.setSize(100,40);
la2.setLocation(240,50);
la2.setOpaque(true);
la2.setHorizontalAlignment(JLabel.CENTER);
la2.setForeground(Color.YELLOW);
la2.setFont(new Font("Arial",Font.ITALIC,40));
la3.setBackground(Color.MAGENTA);
la3.setSize(100,40);
la3.setLocation(380,50);
la3.setOpaque(true);
la3.setHorizontalAlignment(JLabel.CENTER);
la3.setForeground(Color.YELLOW);
la3.setFont(new Font("Arial",Font.ITALIC,40));
la4.setSize(100,10);
la4.setLocation(260,120);
c.setFocusable(true);
c.requestFocus();
setSize(600,200);
setVisible(true);
}
class MyKeyListener extends KeyAdapter {
public void keyPressed(KeyEvent e) {
if(e.getKeyCode()==10) {
int x = (int)(Math.random()*5), y = (int)(Math.random()*5), z = (int)(Math.random()*5);
la1.setText(Integer.toString(x));
la2.setText(Integer.toString(y));
la3.setText(Integer.toString(z));
if(x==y && y==z) {
la4.setText("축하합니다!!");
}
else {
la4.setText("아쉽군요");
}
}
}
}
public static void main(String[] args) {
new Main();
}
}
/*
Math.random() : 0이상 1미만의 랜덤 실수 0.8 0.12 0.7777 0.99999
Math.random()*5 : 0이상 5미만의 랜덤 실수
(int)(Math.random()*5) : 0이상 5 미만의 랜덤 정수
(int)(Math.random())*5 : 0 (x)
*/
/*
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
public Main() {
setTitle("레이블 예제");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container c=getContentPane();
c.setLayout(new FlowLayout());
JLabel textLabel =new JLabel("ㅎㅇ");
ImageIcon beauty =new ImageIcon("beauty.png");
JLabel imageLabel=new JLabel(beauty);
ImageIcon normalIcon =new ImageIcon("normalIcon.png");
JLabel label =new JLabel("normal",normalIcon,SwingConstants.CENTER);
c.add(textLabel);
c.add(imageLabel);
c.add(label);
setSize(400,600);
setVisible(true);
}
public static void main(String[] args) {
new Main();
}
}
*/
/*
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
public Main() {
setTitle("이미지 버튼 예제");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container c= getContentPane();
c.setLayout(new FlowLayout());
ImageIcon normalIcon=new ImageIcon("normalIcon2.png");
ImageIcon rolloverIcon=new ImageIcon("rolloverIcon.png");
ImageIcon pressedIcon =new ImageIcon("pressedIcon.png");
JButton btn=new JButton("call~~",normalIcon);
btn.setPressedIcon(pressedIcon);
btn.setRolloverIcon(rolloverIcon);
c.add(btn);
setSize(250,150);
setVisible(true);
}
public static void main(String[] args) {
new Main();
}
}
*/
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Main extends JFrame {
JButton btn1=new JButton(new ImageIcon("left-arrow.png"));
JButton btn2=new JButton(new ImageIcon("right-arrow.png"));
JPanel p1 = new JPanel();
int iconnum=0;
ImageIcon[] icon = new ImageIcon[4];
JLabel la = new JLabel(new ImageIcon("국기-1.png"));
Container c= getContentPane();
public Main() {
setTitle("Open Challenge 11");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
c.setLayout(new BorderLayout());
icon[0] = new ImageIcon("국기-1.png");
icon[1] = new ImageIcon("국기-2.png");
icon[2] = new ImageIcon("국기-3.png");
icon[3] = new ImageIcon("국기-4.png");
c.add(p1, BorderLayout.CENTER);
p1.add(la);
btn1.addActionListener(new MyActionListener());
btn2.addActionListener(new MyActionListener());
JPanel p2 = new JPanel();
p2.setLayout(new FlowLayout());
c.add(p2,BorderLayout.SOUTH);
p2.add(btn1);
p2.add(btn2);
setVisible(true);
setSize(500, 500);
}
//num 0 1 2 3 4 5 6 7 8 9
//num%4 0 1 2 3 0 1 2 3 0 1
class MyActionListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
JButton pressed_btn = (JButton)e.getSource();
if(pressed_btn.equals(btn2)) {// ->
iconnum=(iconnum+1)%4;
la.setIcon(icon[iconnum]);
c.repaint();
}
else {// <-
if(iconnum==0) iconnum=3;
else iconnum=(iconnum-1);
la.setIcon(icon[iconnum]);
c.repaint();
}
}
}
public static void main(String[] args) {
new Main();
}
}