import java.awt.Color;
import java.awt.Font;

// 方格類
public class Check {
 public int value;

 Font font1 = new Font("宋體", Font.BOLD, 46);
 Font font2 = new Font("宋體", Font.BOLD, 40);
 Font font3 = new Font("宋體", Font.BOLD, 34);
 Font font4 = new Font("宋體", Font.BOLD, 28);
 Font font5 = new Font("宋體", Font.BOLD, 22);

 public Check() {
 value = 0; //value為方格中數(shù)字
 }
 //字體顏色
 public Color getForeground() {
 switch (value) {
 case 0:
 return new Color(0xcdc1b4);//0的顏色與背景色一致，相當于沒有數(shù)字
 case 2:
 case 4:
 return Color.BLACK;
 default:
 return Color.WHITE;
 }
 }

 //字體背景顏色，即方格顏色
 public Color getBackground() {
 switch (value) {
 case 0:
 return new Color(0xcdc1b4);
 case 2:
 return new Color(0xeee4da);
 case 4:
 return new Color(0xede0c8);
 case 8:
 return new Color(0xf2b179);
 case 16:
 return new Color(0xf59563);
 case 32:
 return new Color(0xf67c5f);
 case 64:
 return new Color(0xf65e3b);
 case 128:
 return new Color(0xedcf72);
 case 256:
 return new Color(0xedcc61);
 case 512:
 return new Color(0xedc850);
 case 1024:
 return new Color(0xedc53f);
 case 2048:
 return new Color(0xedc22e);
 case 4096:
 return new Color(0x65da92);
 case 8192:
 return new Color(0x5abc65);
 case 16384:
 return new Color(0x248c51);
 default:
 return new Color(0x248c51);
 }
 }

 public Font getCheckFont() {
 if (value < 10) {
 return font1;
 }
 if (value < 100) {
 return font2;
 }
 if (value < 1000) {
 return font3;
 }
 if (value < 10000) {
 return font4;
 }

 return font5;
 }

}

import java.awt.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class GameView{
 private static final int jframeWidth = 405;//窗口寬高
 private static final int jframeHeight = 530;
 private static int score = 0;

 Font topicFont = new Font("微軟雅黑", Font.BOLD, 50);//主題字體
 Font scoreFont = new Font("微軟雅黑", Font.BOLD, 28);//得分字體
 Font explainFont = new Font("宋體", Font.PLAIN,20);//提示字體

 private JFrame jframeMain;
 private JLabel jlblTitle;
 private JLabel jlblScoreName;
 private JLabel jlblScore;
 private JLabel jlblTip;
 private GameBoard gameBoard;

 public GameView() {
 init();
 }

 public void init() {
 //1、創(chuàng)建窗口
 jframeMain = new JFrame("2048小游戲");
 jframeMain.setSize(jframeWidth, jframeHeight);
 jframeMain.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 jframeMain.setLocationRelativeTo(null);//窗口顯示位置居中
 jframeMain.setResizable(false);
 jframeMain.setLayout(null);//設(shè)置絕對布局，以便后面可以用setBounds設(shè)置位置

 jlblTitle = new JLabel("2048", JLabel.CENTER);
 jlblTitle.setFont(topicFont);
 jlblTitle.setForeground(Color.BLACK);
 jlblTitle.setBounds(50, 0, 150, 60);
 jframeMain.add(jlblTitle);


 //2、框架窗口搭建好，則需向里面開始添加內(nèi)容
 //設(shè)置字體及其顏色、位置
 jlblScoreName = new JLabel("得 分", JLabel.CENTER);
 jlblScoreName.setFont(scoreFont);
 jlblScoreName.setForeground(Color.WHITE);
 jlblScoreName.setOpaque(true);
 jlblScoreName.setBackground(Color.GRAY);
 jlblScoreName.setBounds(250, 0, 120, 30);
 jframeMain.add(jlblScoreName);

 //3、得分區(qū)(得分名+分數(shù))
 jlblScore = new JLabel("0", JLabel.CENTER);
 jlblScore.setFont(scoreFont);
 jlblScore.setForeground(Color.WHITE);
 jlblScore.setOpaque(true);
 jlblScore.setBackground(Color.GRAY);
 jlblScore.setBounds(250, 30, 120, 30);
 jframeMain.add(jlblScore);

 //4、提示說明區(qū)
 jlblTip = new JLabel("操作: ↑ ↓ ← →, 按esc鍵重新開始 ",
 JLabel.CENTER);
 jlblTip.setFont(explainFont);
 jlblTip.setForeground(Color.DARK_GRAY);
 jlblTip.setBounds(0, 60, 400, 40);
 jframeMain.add(jlblTip);

 //5、主游戲面板區(qū)
 gameBoard = new GameBoard();
 gameBoard.setBounds(0, 100, 400, 400);
 gameBoard.setBackground(Color.GRAY);
 gameBoard.setFocusable(true);//焦點即當前正在操作的組件，也就是移動的數(shù)字
 gameBoard.setLayout(new FlowLayout());
 jframeMain.add(gameBoard);
 }

 // 游戲面板
 class GameBoard extends JPanel implements KeyListener {
 private static final int CHECK_GAP = 10;//方格之間的間隙
 private static final int CHECK_SIZE = 85;//方格大小
 private static final int CHECK_ARC = 20;//方格弧度

 private Check[][] checks = new Check[4][4];
 private boolean isadd = true;

 public GameBoard() {
 initGame();
 addKeyListener(this);
 }

 private void initGame() {
 score = 0;
 for (int indexRow = 0; indexRow < 4; indexRow++) {
 for (int indexCol = 0; indexCol < 4; indexCol++) {
 checks[indexRow][indexCol] = new Check();
 }
 }
 // 最開始時生成兩個數(shù)
 isadd = true;
 createCheck();
 isadd = true;
 createCheck();
 }

 @Override
 public void keyPressed(KeyEvent e) {
 switch (e.getKeyCode()) {
 case KeyEvent.VK_ESCAPE:
 initGame();//重新開始游戲（初始化游戲）
 break;
 case KeyEvent.VK_LEFT:
 moveLeft();
 createCheck();//調(diào)用一次方法創(chuàng)建一個方格數(shù)字
 judgeGameOver();//創(chuàng)建后判斷是否GameOver，若所有格子均滿即跳出GameOver
 break;
 case KeyEvent.VK_RIGHT:
 moveRight();
 createCheck();
 judgeGameOver();
 break;
 case KeyEvent.VK_UP:
 moveUp();
 createCheck();
 judgeGameOver();
 break;
 case KeyEvent.VK_DOWN:
 moveDown();
 createCheck();
 judgeGameOver();
 break;
 default:
 break;//按其他鍵沒有反應(yīng)
 }
 repaint();//刷新，會自動調(diào)用paint()方法，重新繪制移動后的圖
 }


 private void createCheck() {
 List<Check> list = getEmptyChecks();

 if (!list.isEmpty() && isadd) {
 Random random = new Random();
 int index = random.nextInt(list.size());
 Check check = list.get(index);
 // 2, 4出現(xiàn)概率3:1
 int randomValue = random.nextInt(4);
 check.value = ( randomValue % 3 == 0 || randomValue % 3 == 1) ? 2 : 4;//只有[0,4)中的2才能生成4
 isadd = false;
 }
 }

 // 獲取空白方格
 private List<Check> getEmptyChecks() {
 List<Check> checkList = new ArrayList<>();
 for (int i = 0; i < 4; i++) {
 for (int j = 0; j < 4; j++) {
 if (checks[i][j].value == 0) {
 checkList.add(checks[i][j]);
 }
 }
 }
 return checkList;
 }
 //是否全部格子占滿，全部占滿則GameOver
 private boolean judgeGameOver() {
 jlblScore.setText(score + "");

 if (!getEmptyChecks().isEmpty()) {
 return false;
 }

 for (int i = 0; i < 3; i++) {
 for (int j = 0; j < 3; j++) {
 //判斷是否存在可合并的方格
 if (checks[i][j].value == checks[i][j + 1].value
 || checks[i][j].value == checks[i + 1][j].value) {
 return false;
 }
 }
 }

 return true;
 }

 private void moveLeft() {
 //找到一個非空格子后checks[i][j].value > 0，可分為三種情況處理
 for (int i = 0; i < 4; i++) {
 for (int j = 1, index = 0; j < 4; j++) {
 if (checks[i][j].value > 0) {
 //第一種情況：checks[i][j]（非第1列）與checks[i][index]的數(shù)相等，則合并乘以2，且得分增加
 if (checks[i][j].value == checks[i][index].value) {
 score += checks[i][index].value *= 2;
 checks[i][j].value = 0;
 isadd = true;
 } else if (checks[i][index].value == 0) {
 //第二種：若checks[i][index]為空格子，checks[i][j]就直接移到最左邊checks[i][index]
 checks[i][index].value = checks[i][j].value;
 checks[i][j].value = 0;
 isadd = true;
 } else if (checks[i][++index].value == 0) {
 //第三種：若checks[i][index]不為空格子，并且數(shù)字也不相等，若其旁邊為空格子，則移到其旁邊
 checks[i][index].value = checks[i][j].value;
 checks[i][j].value = 0;
 isadd = true;
 }
 }
 }
 }
 }

 private void moveRight() {
 for (int i = 0; i < 4; i++) {
 for (int j = 2, index = 3; j >= 0; j--) {
 if (checks[i][j].value > 0) {
 if (checks[i][j].value == checks[i][index].value) {
 score += checks[i][index].value *= 2;
 checks[i][j].value = 0;
 isadd = true;
 } else if (checks[i][index].value == 0) {
 checks[i][index].value = checks[i][j].value;
 checks[i][j].value = 0;
 isadd = true;
 } else if (checks[i][--index].value == 0) {
 checks[i][index].value = checks[i][j].value;
 checks[i][j].value = 0;
 isadd = true;
 }
 }
 }
 }
 }

 private void moveUp() {
 for (int i = 0; i < 4; i++) {
 for (int j = 1, index = 0; j < 4; j++) {
 if (checks[j][i].value > 0) {
 if (checks[j][i].value == checks[index][i].value) {
 score += checks[index][i].value *= 2;
 checks[j][i].value = 0;
 isadd = true;
 } else if (checks[index][i].value == 0) {
 checks[index][i].value = checks[j][i].value;
 checks[j][i].value = 0;
 isadd = true;
 } else if (checks[++index][i].value == 0){
 checks[index][i].value = checks[j][i].value;
 checks[j][i].value = 0;
 isadd = true;
 }
 }
 }
 }
 }

 private void moveDown() {
 for (int i = 0; i < 4; i++) {
 for (int j = 2, index = 3; j >= 0; j--) {
 if (checks[j][i].value > 0) {
 if (checks[j][i].value == checks[index][i].value) {
 score += checks[index][i].value *= 2;
 checks[j][i].value = 0;
 isadd = true;
 } else if (checks[index][i].value == 0) {
 checks[index][i].value = checks[j][i].value;
 checks[j][i].value = 0;
 isadd = true;
 } else if (checks[--index][i].value == 0) {
 checks[index][i].value = checks[j][i].value;
 checks[j][i].value = 0;
 isadd = true;
 }
 }
 }
 }
 }

 @Override
 public void paint(Graphics g) {
 super.paint(g);
 for (int i = 0; i < 4; i++) {
 for (int j = 0; j < 4; j++) {
 drawCheck(g, i, j);
 }
 }

 // GameOver
 if (judgeGameOver()) {
 g.setColor(new Color(64, 64, 64, 100));//RGBA最后一個A可以視為透明度
 g.fillRect(0, 0, getWidth(), getHeight());//填充矩形（游戲面板），將暗黑色填充上去
 g.setColor(Color.WHITE);
 g.setFont(topicFont);
 FontMetrics fms = getFontMetrics(topicFont);//FontMetrics字體測量，該類是Paint的內(nèi)部類，通過getFontMetrics()方法可獲取字體相關(guān)屬性
 String value = "Game Over!";
 g.drawString(value, (getWidth()-fms.stringWidth(value)) / 2, getHeight() / 2);//字體居中顯示
 }
 }

 // 繪制方格
 // Graphics2D 類是Graphics 子類，擁有強大的二維圖形處理能力
 private void drawCheck(Graphics g, int i, int j) {
 Graphics2D gg = (Graphics2D) g;
 //下面兩句是抗鋸齒模式，計算和優(yōu)化消除文字鋸齒，字體更清晰順滑
 gg.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
 gg.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_NORMALIZE);
 //獲取方格
 Check check = checks[i][j];
 //不同數(shù)字設(shè)置背景色
 gg.setColor(check.getBackground());
 // 繪制圓角
 gg.fillRoundRect(CHECK_GAP + (CHECK_GAP + CHECK_SIZE) * j,
 CHECK_GAP + (CHECK_GAP + CHECK_SIZE) * i,
 CHECK_SIZE, CHECK_SIZE, CHECK_ARC, CHECK_ARC);
 //繪制字體及其顏色
 gg.setColor(check.getForeground());
 gg.setFont(check.getCheckFont());

 // 文字測量，并對文字進行繪制
 FontMetrics fms = getFontMetrics(check.getCheckFont());
 String value = String.valueOf(check.value);
 //使用此圖形上下文的當前顏色繪制由指定迭代器給定的文本。
 //getAscent()是FontMetrics中的一個方法，
 //getDescent() 為降部
 gg.drawString(value,
 CHECK_GAP + (CHECK_GAP + CHECK_SIZE) * j +
 (CHECK_SIZE - fms.stringWidth(value)) / 2,
 CHECK_GAP + (CHECK_GAP + CHECK_SIZE) * i +
 (CHECK_SIZE - fms.getAscent() - fms.getDescent()) / 2
 + fms.getAscent());//讓數(shù)字居中顯示
 }

 @Override
 public void keyReleased(KeyEvent e) {
 }

 @Override
 public void keyTyped(KeyEvent e) {
 }

 }

 public void showView() {
 jframeMain.setVisible(true);
 }

}

public class Main {
 public static void main(String[] args) {
 new GameView().showView();
 }
}

Graphics2D gg = (Graphics2D) g;
gg.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
gg.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL,RenderingHints.VALUE_STROKE_NORMALIZE);