java 错误 NoClassDefFoundError 可能是由于长脚本？

Question

你好我的项目需要帮助。 我写了一个长文件。现在，当我运行它时出现错误，但是当我删除一个部件时，我可以正常运行它。例如，当我删除代码的顶部时，它运行良好，没有错误。当我读取顶部并移除底部时，它也可以正常工作。

但是当我运行完整文件时出现以下错误

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: Formule_Form/Formule_Form_4
    at Form.Form_1.<init>(Form_1.java:49)
    at Main.Main.<init>(Main.java:34)
    at Main.Main$2.run(Main.java:133)
    at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:318)
    at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:773)
    at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720)
    at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
    at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
    at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742)
    at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Caused by: java.lang.ClassNotFoundException: Formule_Form.Formule_Form_4
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    ... 16 more

    
        public class Formule_Form_4 extends javax.swing.JPanel implements MouseListener,ActionListener,FocusListener,KeyListener {
    
    
          
    
        public Formule_Form_4() {
            initComponents();
    //        formuleUitkomstKnop01.addMouseListener(this);
            rekenMachineTextVeld1.addMouseListener(this);
            rekenMachineTextVeld1.addKeyListener(this);
    
            rekenMachineTextVeld1.addFocusListener(this);
            rekenMachineTextVeld2.addFocusListener(this);
    //        formuleUitkomstKnop01.setVisible(true);
     
        }
    
            @Override
        public void mouseClicked(MouseEvent e) {
           
        }
    
        @Override
        public void mousePressed(MouseEvent e) {
            
    //        double num_1 = Double.parseDouble(rekenMachineTextVeld1.getText());
     
        }        
    
        @Override
        public void mouseReleased(MouseEvent e) {
            
        }
    
        @Override
        public void mouseEntered(MouseEvent e) {
            
        }
    
        @Override
        public void mouseExited(MouseEvent e) {
            
        }
    
        @Override
        public void actionPerformed(ActionEvent e) {
            
        }
    
        @Override
        public void focusGained(FocusEvent e) {
            if(e.getSource() == rekenMachineTextVeld1) { 
                rekenMachineTextVeld1.setText("");
                rekenMachineTextVeld2.setText("");
            } 
            if(e.getSource() == rekenMachineTextVeld2) { 
                rekenMachineTextVeld1.setText("");
                rekenMachineTextVeld2.setText("");
            }                
        }
    
        @Override
        public void focusLost(FocusEvent e) {
            if(e.getSource() == rekenMachineTextVeld1) {        
                rekenMachineTextVeld2.setText("");
            }  
    //        if(e.getSource() == rekenMachineTextVeld2) {        
    //            rekenMachineTextVeld1.setText("");
    //        }        
        }
    
        @Override
        public void keyTyped(KeyEvent e) {
          
        }
    
        @Override
        public void keyPressed(KeyEvent e) {
     
        }
        @Override
        public void keyReleased(KeyEvent e) {
            double num_1 = Double.parseDouble(rekenMachineTextVeld1.getText()); 
            
            //-------------------------------------------------[GRAM]-------------------------------------------------\\
            
            //--------------------------------------\\
            //||||||||||||||||||||||||||||||||||||||\\
            //||||||||||||||||||||||||||||||||||||||\\
            //<------------(GRAM -> GRAM)------------>        
            double gram = 1;
          
            switch(e.getKeyChar()){
                case KeyEvent.VK_0:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }
            }
            switch(e.getKeyChar()){
                case KeyEvent.VK_1:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            }
            switch(e.getKeyChar()){
                case KeyEvent.VK_2:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            } 
            switch(e.getKeyChar()){
                case KeyEvent.VK_3:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            }
            switch(e.getKeyChar()){
                case KeyEvent.VK_4:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            }
            switch(e.getKeyChar()){
                case KeyEvent.VK_5:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            } 
            switch(e.getKeyChar()){
                case KeyEvent.VK_6:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            }
            switch(e.getKeyChar()){
                case KeyEvent.VK_7:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            }
            switch(e.getKeyChar()){
                case KeyEvent.VK_8:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            }
            switch(e.getKeyChar()){
                case KeyEvent.VK_9:{
                    if(jComboBox1.getSelectedItem().equals("gram(g)") && jComboBox2.getSelectedItem().equals("gram(g)")) {
                        double result = num_1 * gram;
                        rekenMachineTextVeld2.setText(String.valueOf(result));
                        break;
                    }                 
                }        
            }'

Answer 1

你们都是对的……但奇怪的是，我相信类在正确的路径中，因为当我删除它加载的脚本的一部分（Formule_Form_4 的一部分）时没有任何问题。 顶部或底部但是当我重新添加它时找不到路径。它告诉我 Formule_Form_4 没有主要方法。这就是为什么我认为可能是因为长度，但事实并非如此。