當我嘗試運行它時，為什么我的程序會凍結/崩潰？

Question

這不是一個完整的程序，但我想知道為什么當我按下“JButton”時它凍結。 我目前正在制作一個骰子游戲，到目前為止一切正常，但我不明白為什么它不會在此刻運行。 感謝您事先的幫助:)

PS。 我在方法diceLogic中添加了while循環后問題就開始了。

 /* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package dicegame_leonardasp; /** * * @author LeoAsp */ import java.awt.Dimension; import java.awt.Image; import javax.swing.JLabel; import javax.swing.ImageIcon; import java.util.Random; import javafx.scene.control.Cell; public class DiceGameGui extends javax.swing.JFrame { //Instansvariabel //Skapa instans av Randomklassen Random rand = new Random(); public DiceGameGui() { initComponents(); } public String doMessage() { String message = ""; return message; } public String doReDice() { String image = ""; int randNum = rand.nextInt(6 - 1) + 1; if (randNum == 1) { image = "one.gif"; } else if (randNum == 2) { image = "two.gif"; } else if (randNum == 3) { image = "three.gif"; } else if (randNum == 4) { image = "four.gif"; } else if (randNum == 5) { image = "five.gif"; } else if (randNum == 6) { image = "six.gif"; } else { dispose(); } return image; } public void diceLogic(int players, int dice) { jDiceResult.removeAll(); jDiceResult.setLayout(new java.awt.GridLayout(6, 5)); JLabel playersArray[][] = new JLabel[players][dice]; int j; int i; for (i = 0; i <= players; i++) { for (j = 0; j < dice; j++) { playersArray[i][j] = new JLabel(); playersArray[i][j].setIcon(new ImageIcon(doReDice())); playersArray[i][j].setPreferredSize(new Dimension(60, 50)); // playersArray[i][j].setPreferredSize(new Dimension(20, 20)); //playersArray[i][j].setMinimumSize(new Dimension(20, 20)); //playersArray[i][j].setMaximumSize(new Dimension(20, 20)); jDiceResult.add(playersArray[i][j]); jDiceResult.revalidate(); jDiceResult.repaint(); } while (j <= 6) { jDiceResult.add(javax.swing.Box.createGlue()); } } } /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @ SuppressWarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="Generated Code"> private void initComponents() { jLabel1 = new javax.swing.JLabel(); jLabel2 = new javax.swing.JLabel(); jLabel3 = new javax.swing.JLabel(); jBoxPlayers = new javax.swing.JComboBox(); jBoxDice = new javax.swing.JComboBox(); jBtnRoll = new javax.swing.JButton(); jScrollPane1 = new javax.swing.JScrollPane(); jTextArea1 = new javax.swing.JTextArea(); jButton1 = new javax.swing.JButton(); jDiceResult = new javax.swing.JPanel(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); jLabel1.setFont(new java.awt.Font("Menlo", 0, 18)); // NOI18N jLabel1.setText("Players:"); jLabel2.setFont(new java.awt.Font("Menlo", 0, 18)); // NOI18N jLabel2.setText("Dice:"); jLabel3.setFont(new java.awt.Font("Menlo", 0, 18)); // NOI18N jBoxPlayers.setFont(new java.awt.Font("Menlo", 1, 14)); // NOI18N jBoxPlayers.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "1", "2", "3", "4", "5" })); jBoxPlayers.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jBoxPlayersActionPerformed(evt); } }); jBoxDice.setFont(new java.awt.Font("Menlo", 1, 14)); // NOI18N jBoxDice.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "1", "2", "3", "4", "5", "6" })); jBoxDice.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jBoxDiceActionPerformed(evt); } }); jBtnRoll.setFont(new java.awt.Font("Menlo", 0, 18)); // NOI18N jBtnRoll.setText("Roll the Dice"); jBtnRoll.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jBtnRollActionPerformed(evt); } }); jTextArea1.setEditable(false); jTextArea1.setColumns(20); jTextArea1.setRows(5); jScrollPane1.setViewportView(jTextArea1); jButton1.setFont(new java.awt.Font("Menlo", 0, 14)); // NOI18N jButton1.setText("Show Highscore"); jDiceResult.setBorder(javax.swing.BorderFactory.createBevelBorder(javax.swing.border.BevelBorder.RAISED)); jDiceResult.setPreferredSize(new java.awt.Dimension(250, 300)); javax.swing.GroupLayout jDiceResultLayout = new javax.swing.GroupLayout(jDiceResult); jDiceResult.setLayout(jDiceResultLayout); jDiceResultLayout.setHorizontalGroup( jDiceResultLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGap(0, 246, Short.MAX_VALUE) ); jDiceResultLayout.setVerticalGroup( jDiceResultLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGap(0, 296, Short.MAX_VALUE) ); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addContainerGap() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 175, javax.swing.GroupLayout.PREFERRED_SIZE) .addGap(0, 0, Short.MAX_VALUE)) .addGroup(layout.createSequentialGroup() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false) .addComponent(jBoxPlayers, 0, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)) .addGap(91, 91, 91) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addComponent(jLabel2) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(jLabel3)) .addComponent(jBoxDice, javax.swing.GroupLayout.PREFERRED_SIZE, 88, javax.swing.GroupLayout.PREFERRED_SIZE))) .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGap(18, 18, 18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jBtnRoll, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addComponent(jDiceResult, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))) .addContainerGap()) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addContainerGap() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel1) .addComponent(jLabel2) .addComponent(jLabel3)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jBoxPlayers, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addComponent(jBoxDice, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))) .addComponent(jBtnRoll, javax.swing.GroupLayout.PREFERRED_SIZE, 57, javax.swing.GroupLayout.PREFERRED_SIZE)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING) .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 347, javax.swing.GroupLayout.PREFERRED_SIZE) .addComponent(jDiceResult, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(jButton1) .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)) ); pack(); } // </editor-fold> private void jBoxPlayersActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: } private void jBoxDiceActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: } private void jBtnRollActionPerformed(java.awt.event.ActionEvent evt) { int dice = Integer.parseInt(jBoxDice.getSelectedItem().toString()); int players = Integer.parseInt(jBoxPlayers.getSelectedItem().toString()); diceLogic(players, dice); } /** * @param args the command line arguments */ public static void main(String args[]) { //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "> /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info: javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (ClassNotFoundException ex) { java.util.logging.Logger.getLogger(DiceGameGui.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (InstantiationException ex) { java.util.logging.Logger.getLogger(DiceGameGui.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (IllegalAccessException ex) { java.util.logging.Logger.getLogger(DiceGameGui.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (javax.swing.UnsupportedLookAndFeelException ex) { java.util.logging.Logger.getLogger(DiceGameGui.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } //</editor-fold> /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new DiceGameGui().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JComboBox jBoxDice; private javax.swing.JComboBox jBoxPlayers; private javax.swing.JButton jBtnRoll; private javax.swing.JButton jButton1; private javax.swing.JPanel jDiceResult; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel2; private javax.swing.JLabel jLabel3; private javax.swing.JScrollPane jScrollPane1; private javax.swing.JTextArea jTextArea1; // End of variables declaration } 

Answer 1

這就是問題：

while (j <= 6) {
    jDiceResult.add(javax.swing.Box.createGlue());
}

使用此行，您可以創建無限循環，因為您檢查j<=6但是不更改j的值，因此j<=6始終為true 。
我猜你想改變while對if 。

Answer 2

我猜：

while (j <= 6) {
    jDiceResult.add(javax.swing.Box.createGlue());
}

我想可能應該是：

if (j <= 6) {
    jDiceResult.add(javax.swing.Box.createGlue());
}