Java Error错误的sym类型:setDefaultCloseOperation

时间:2013-10-31 08:28:35

标签: java swing user-interface jframe

我对Java很陌生,特别是在构建JFrame时。我一直在收到上述错误,问题似乎来自Generated Code。 请协助我清除错误并了解导致错误的原因。

package calculator;

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


public class CalcForm {

    /**
     * Creates new form CalcForm
     */
    public CalcForm() {
        initComponents();
   }



     //The Auto-Generated Code begins here
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

        jLabel1 = new javax.swing.JLabel();
        input1 = new javax.swing.JTextField();
        jLabel2 = new javax.swing.JLabel();
        input2 = new javax.swing.JTextField();
        btnAdd = new javax.swing.JButton();
        btnLess = new javax.swing.JButton();
        btnEquals = new javax.swing.JButton();
        jLabel3 = new javax.swing.JLabel();
        disp = new javax.swing.JTextField();

        //The two lines below are highlighted in RED
        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Simple Calcucator");

        jLabel1.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel1.setText("First Input:");

        input1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                input1ActionPerformed(evt);
            }
        });

        jLabel2.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel2.setText("Second Input:");

        input2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                input2ActionPerformed(evt);
            }
        });

        btnAdd.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        btnAdd.setText("+");
        btnAdd.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnAddActionPerformed(evt);
            }
        });

        btnLess.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        btnLess.setText("-");
        btnLess.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnLessActionPerformed(evt);
            }
        });

        btnEquals.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        btnEquals.setText("=");
        btnEquals.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnEqualsActionPerformed(evt);
            }
        });

        jLabel3.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel3.setText("Your Answer is:");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(79, 79, 79)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                    .addComponent(btnEquals, javax.swing.GroupLayout.PREFERRED_SIZE, 181, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addGroup(layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                                .addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                .addComponent(jLabel2, javax.swing.GroupLayout.DEFAULT_SIZE, 123, Short.MAX_VALUE))
                            .addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 137, javax.swing.GroupLayout.PREFERRED_SIZE))
                        .addGap(61, 61, 61)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(input1)
                            .addComponent(btnAdd, javax.swing.GroupLayout.PREFERRED_SIZE, 75, javax.swing.GroupLayout.PREFERRED_SIZE)
                            .addGroup(layout.createSequentialGroup()
                                .addGap(116, 116, 116)
                                .addComponent(btnLess, javax.swing.GroupLayout.PREFERRED_SIZE, 65, javax.swing.GroupLayout.PREFERRED_SIZE))
                            .addComponent(input2)
                            .addComponent(disp))))
                .addContainerGap(94, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(34, 34, 34)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 35, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(input1, javax.swing.GroupLayout.PREFERRED_SIZE, 47, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(42, 42, 42)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(btnAdd, javax.swing.GroupLayout.PREFERRED_SIZE, 55, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnLess, javax.swing.GroupLayout.PREFERRED_SIZE, 55, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(31, 31, 31)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 62, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(input2, javax.swing.GroupLayout.PREFERRED_SIZE, 44, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addComponent(btnEquals, javax.swing.GroupLayout.PREFERRED_SIZE, 64, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(25, 25, 25)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 48, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(disp, javax.swing.GroupLayout.PREFERRED_SIZE, 48, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addContainerGap(29, Short.MAX_VALUE))
        );
       //This also has a Red underline
        pack();
    }// </editor-fold>



    private void input1ActionPerformed(java.awt.event.ActionEvent evt) {                                       
        // TODO add your handling code here:
    }                                      

    private void input2ActionPerformed(java.awt.event.ActionEvent evt) {                                       
    }                                      

    private void btnAddActionPerformed(java.awt.event.ActionEvent evt) {                                       

        btnAdd.setActionCommand("+");


    }                                      

    private void btnLessActionPerformed(java.awt.event.ActionEvent evt) {                                        

        btnLess.setActionCommand("-");

    }                                       

    private void btnEqualsActionPerformed(java.awt.event.ActionEvent evt) {                                          

        btnEquals.setActionCommand("=");
        String less = btnLess.getActionCommand();
        String more = btnAdd.getActionCommand();
        double t = 0;
        String x = input2.getText();
        //parseDouble is a method used to read the given object as a double value
        double y = Double.parseDouble(x);

        String a = input1.getText();
        double b = Double.parseDouble(a);
        if (less.equals(evt)) {

            t = b - y;
            disp.setText(String.valueOf(t));

        } else {

            t = b + y;
            disp.setText(String.valueOf(t));

        }

    }                                         

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {



        /*
         * Create and display the form
         */

        java.awt.EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new CalcForm();



            }
        });

    }
    // Variables declaration - do not modify
    private javax.swing.JButton btnAdd;
    private javax.swing.JButton btnEquals;
    private javax.swing.JButton btnLess;
    private javax.swing.JTextField disp;
    private javax.swing.JTextField input1;
    private javax.swing.JTextField input2;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    // End of variables declaration
}

显示的错误是:

Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: Uncompilable source code - Erroneous sym type: setDefaultCloseOperation
    at calculator.CalcForm.initComponents(CalcForm.java:43)
    at calculator.CalcForm.<init>(CalcForm.java:21)
    at calculator.CalcForm$6.run(CalcForm.java:232)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

非常感谢帮助。

1 个答案:

答案 0 :(得分:1)

如果Eclipse的 Problems 视图中仍然存在编译错误,请不要尝试运行您的应用。

您的类不会扩展JFrame,因此它没有任何setDefaultCloseOperation()方法。它也没有任何setTitle()add() pack()等方法。您错过了班级声明中的extends JFrame部分。