java - 如何将此代码从小程序更改为独立应用程序

Question

有谁知道如何将这个小程序制作成应用程序吗？我删除“扩展小程序”后，它不起作用。我不知道如何将其更改为应用程序以及“扩展”后要写什么。

 import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;

    public class BlackjackGUI extends JApplet {

       public void init() {

init() 方法创建组件并布置小程序。 BlackjackCanvas 占据布局的中心位置。 底部是一个带有三个按钮的面板。这 BlackjackCanvas 对象监听来自按钮的事件 并完成程序的所有实际工作。

 setBackground( new Color(130,50,40) );

          BlackjackCanvas board = new BlackjackCanvas();
          getContentPane().add(board, BorderLayout.CENTER);

          JPanel buttonPanel = new JPanel();
          buttonPanel.setBackground( new Color(220,200,180) );
          getContentPane().add(buttonPanel, BorderLayout.SOUTH);

          JButton hit = new JButton( "Hit!" );
          hit.addActionListener(board);
          buttonPanel.add(hit);

          JButton stand = new JButton( "Stand!" );
          stand.addActionListener(board);
          buttonPanel.add(stand);

          JButton newGame = new JButton( "New Game" );
          newGame.addActionListener(board);
          buttonPanel.add(newGame);

       }  // end init()

       public Insets getInsets() {
             // Specify how much space to leave between the edges of
             // the applet and the components it contains.  The background
             // color shows through in this border.
          return new Insets(3,3,3,3);
       }


       // --- The remainder of this class consists of a nested class ---


       class BlackjackCanvas extends JPanel implements ActionListener {

             // A nested class that displays the card game and does all the work
             // of keeping track of the state and responding to user events.

          Deck deck;         // A deck of cards to be used in the game.

          BlackjackHand dealerHand;   // Hand containing the dealer's cards.
          BlackjackHand playerHand;   // Hand containing the user's cards.

          String message;  // A message drawn on the canvas, which changes
                           //    to reflect the state of the game.

          boolean gameInProgress;  // Set to true when a game begins and to false
                                   //   when the game ends.

          Font bigFont;      // Font that will be used to display the message.
          Font smallFont;    // Font that will be used to draw the cards.


          BlackjackCanvas() {
                // Constructor.  Creates fonts and starts the first game.
             setBackground( new Color(0,120,0) );
             smallFont = new Font("SansSerif", Font.PLAIN, 12);
             bigFont = new Font("Serif", Font.BOLD, 14);
             doNewGame();
          }


          public void actionPerformed(ActionEvent evt) {
                 // Respond when the user clicks on a button by calling
                 // the appropriate procedure.  Note that the canvas is
                 // registered as a listener in the BlackjackGUI class.
             String command = evt.getActionCommand();
             if (command.equals("Hit!"))
                doHit();
             else if (command.equals("Stand!"))
                doStand();
             else if (command.equals("New Game"))
                doNewGame();
          }


          void doHit() {
                 // This method is called when the user clicks the "Hit!" button.
                 // First check that a game is actually in progress.  If not, give
                 // an error message and exit.  Otherwise, give the user a card.
                 // The game can end at this point if the user goes over 21 or
                 // if the user has taken 5 cards without going over 21.
             if (gameInProgress == false) {
                message = "Click \"New Game\" to start a new game.";
                repaint();
                return;
             }
             playerHand.addCard( deck.dealCard() );
             if ( playerHand.getBlackjackValue() > 21 ) {
                message = "You've busted!  Sorry, you lose.";
                gameInProgress = false;
             }
             else if (playerHand.getCardCount() == 5) {
                message = "You win by taking 5 cards without going over 21.";
                gameInProgress = false;
             }
             else {
                message = "You have " + playerHand.getBlackjackValue() + ".  Hit or Stand?";
             }
             repaint();
          }


          void doStand() {
                  // This method is called when the user clicks the "Stand!" button.
                  // Check whether a game is actually in progress.  If it is,
                  // the game ends.  The dealer takes cards until either the
                  // dealer has 5 cards or more than 16 points.  Then the 
                  // winner of the game is determined.
             if (gameInProgress == false) {
                message = "Click \"New Game\" to start a new game.";
                repaint();
                return;
             }
             gameInProgress = false;
             while (dealerHand.getBlackjackValue() <= 16 && dealerHand.getCardCount() < 5)
                dealerHand.addCard( deck.dealCard() );
             if (dealerHand.getBlackjackValue() > 21)
                 message = "You win!  Dealer has busted with " + dealerHand.getBlackjackValue() + ".";
             else if (dealerHand.getCardCount() == 5)
                 message = "Sorry, you lose.  Dealer took 5 cards without going over 21.";
             else if (dealerHand.getBlackjackValue() > playerHand.getBlackjackValue())
                 message = "Sorry, you lose, " + dealerHand.getBlackjackValue()
                                                   + " to " + playerHand.getBlackjackValue() + ".";
             else if (dealerHand.getBlackjackValue() == playerHand.getBlackjackValue())
                 message = "Sorry, you lose.  Dealer wins on a tie.";
             else
                 message = "You win, " + playerHand.getBlackjackValue()
                                                   + " to " + dealerHand.getBlackjackValue() + "!";
             repaint();
          }


          void doNewGame() {
                 // Called by the constructor, and called by actionPerformed() if
                 // the use clicks the "New Game" button.  Start a new game.
                 // Deal two cards to each player.  The game might end right then
                 // if one of the players had blackjack.  Otherwise, gameInProgress
                 // is set to true and the game begins.
             if (gameInProgress) {
                     // If the current game is not over, it is an error to try
                     // to start a new game.
                message = "You still have to finish this game!";
                repaint();
                return;
             }
             deck = new Deck();   // Create the deck and hands to use for this game.
             dealerHand = new BlackjackHand();
             playerHand = new BlackjackHand();
             deck.shuffle();
             dealerHand.addCard( deck.dealCard() );  // Deal two cards to each player.
             dealerHand.addCard( deck.dealCard() );
             playerHand.addCard( deck.dealCard() );
             playerHand.addCard( deck.dealCard() );
             if (dealerHand.getBlackjackValue() == 21) {
                 message = "Sorry, you lose.  Dealer has Blackjack.";
                 gameInProgress = false;
             }
             else if (playerHand.getBlackjackValue() == 21) {
                 message = "You win!  You have Blackjack.";
                 gameInProgress = false;
             }
             else {
                 message = "You have " + playerHand.getBlackjackValue() + ".  Hit or stand?";
                 gameInProgress = true;
             }
             repaint();
          }  // end newGame();


          public void paintComponent(Graphics g) {
                // The paint method shows the message at the bottom of the
                // canvas, and it draws all of the dealt cards spread out
                // across the canvas.

             super.paintComponent(g); // fill with background color.

             g.setFont(bigFont);
             g.setColor(Color.green);
             g.drawString(message, 10, getSize().height - 10);

             // Draw labels for the two sets of cards.

             g.drawString("Dealer's Cards:", 10, 23);
             g.drawString("Your Cards:", 10, 153);

             // Draw dealer's cards.  Draw first card face down if
             // the game is still in progress,  It will be revealed
             // when the game ends.

             g.setFont(smallFont);
             if (gameInProgress)
                drawCard(g, null, 10, 30);
             else
                drawCard(g, dealerHand.getCard(0), 10, 30);
             for (int i = 1; i < dealerHand.getCardCount(); i++)
                drawCard(g, dealerHand.getCard(i), 10 + i * 90, 30);

             // Draw the user's cards.

             for (int i = 0; i < playerHand.getCardCount(); i++)
                drawCard(g, playerHand.getCard(i), 10 + i * 90, 160);

          }  // end paint();


          void drawCard(Graphics g, Card card, int x, int y) {
                  // Draws a card as a 80 by 100 rectangle with
                  // upper left corner at (x,y).  The card is drawn
                  // in the graphics context g.  If card is null, then
                  // a face-down card is drawn.  (The cards are 
                  // rather primitive.)
             if (card == null) {  
                    // Draw a face-down card
                g.setColor(Color.blue);
                g.fillRect(x,y,80,100);
                g.setColor(Color.white);
                g.drawRect(x+3,y+3,73,93);
                g.drawRect(x+4,y+4,71,91);
             }
             else {
                g.setColor(Color.white);
                g.fillRect(x,y,80,100);
                g.setColor(Color.gray);
                g.drawRect(x,y,79,99);
                g.drawRect(x+1,y+1,77,97);
                if (card.getSuit() == Card.DIAMONDS || card.getSuit() == Card.HEARTS)
                   g.setColor(Color.red);
                else
                   g.setColor(Color.black);
                g.drawString(card.getValueAsString(), x + 10, y + 30);
                g.drawString("of", x+ 10, y + 50);
                g.drawString(card.getSuitAsString(), x + 10, y + 70);
             }
          }  // end drawCard()


       } // end nested class BlackjackCanvas


    } // end class BlackjackGUI

Answer 1

如果您的游戏使用基于 Applet 的方法，您可能只想保持这种方式。您可以创建一个包装器窗口来容纳您的小程序，然后它就可以正常运行。您需要做的就是向您的 applet 类添加一个 main 方法，如下所示:

public static void main(String[] args) {
    JFrame mainWindow = new JFrame("Blackjack"); // You can change "Blackjack" to anything, it will display that as the window title
    mainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    mainWindow.setResizeable(false); // If your applet can handle resizing, you can remove this line
    BackjackGUI applet = new BlackjackGUI();
    applet.init();
    mainWindow.add(applet);
    mainWindow.setSize(applet.getSize());
    mainWindow.setVisible(true);
}

这将允许您的应用程序既作为小程序又作为独立应用程序运行。