如何糾正？

Question

import java.awt.Container; 
import java.awt.GridBagConstraints; 
import java.awt.GridBagLayout; 
import java.awt.Insets; 
import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import java.util.ArrayList; 

import javax.swing.JButton; 
import javax.swing.JFrame; 
import javax.swing.JLabel; 
import javax.swing.JOptionPane; 
import javax.swing.JTextField; 

//public class AddressBookDemo implements ActionListener 
public class AddressBookDemo 
{ 
    ArrayList personsList; 
    //PersonDAO pDAO; 

JFrame appFrame; 

//JLabel jlbSl; 
JTextField jtfQuestion; 
JButton jbnClear, jbnForward, jbnBack, jbnFinish; 

//String name, address, email; 
//int phone; 
//int recordNumber; // used to naviagate using >> and << buttons 
Container cPane; 


public static void main(String args[]){ 
     new AddressBookDemo(); 
    } 

public void createGUI(){ 

    /*Create a frame, get its contentpane and set layout*/ 
    appFrame = new JFrame("Address Book"); 

    cPane = appFrame.getContentPane(); 
    cPane.setLayout(new GridBagLayout()); 

    //Arrange components on contentPane and set Action Listeners to each JButton 
    arrangeComponents(); 

    appFrame.setSize(240,300); 
    appFrame.setResizable(false); 
    appFrame.setVisible(true); 
    appFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

} 

public void arrangeComponents(){ 
    //jlbName = new JLabel("Name"); 

    jtfQuestion = new JTextField(20); 



    jbnClear = new JButton("Clear"); 
    jbnForward = new JButton(">>"); 
    jbnBack = new JButton("<<"); 
    jbnFinish = new JButton("Finish"); 
    //GridBagConstraints gridBagConstraintsx01 = new GridBagConstraints(); 
    //gridBagConstraintsx01.gridx = 0; 
    //gridBagConstraintsx01.gridy = 0; 
    //gridBagConstraintsx01.insets = new Insets(5, 5, 5, 5); 
    //cPane.add(jlbName, gridBagConstraintsx01); 
    GridBagConstraints gridBagConstraintsx04 = new GridBagConstraints(); 
    gridBagConstraintsx04.gridx = 1; 
    gridBagConstraintsx04.insets = new Insets(5, 5, 5, 5); 
    gridBagConstraintsx04.gridy = 1; 
    gridBagConstraintsx04.gridwidth = 2; 
    gridBagConstraintsx04.fill = GridBagConstraints.BOTH; 
    cPane.add(jtfQuestion, gridBagConstraintsx04); 

    GridBagConstraints gridBagConstraintsx12 = new GridBagConstraints(); 
    gridBagConstraintsx12.gridx = 0; 
    gridBagConstraintsx12.gridy = 5; 
    gridBagConstraintsx12.insets = new Insets(5, 5, 5, 5); 
    cPane.add(jbnBack, gridBagConstraintsx12); 

    GridBagConstraints gridBagConstraintsx14 = new GridBagConstraints(); 
    gridBagConstraintsx14.gridx = 2; 
    gridBagConstraintsx14.gridy = 5; 
    gridBagConstraintsx14.insets = new Insets(5, 5, 5, 5); 
    cPane.add(jbnForward, gridBagConstraintsx14); 

    GridBagConstraints gridBagConstraintsx15 = new GridBagConstraints(); 
    gridBagConstraintsx15.gridx = 1; 
    gridBagConstraintsx15.insets = new Insets(5, 5, 5, 5); 
    gridBagConstraintsx15.gridy = 6; 
    cPane.add(jbnClear, gridBagConstraintsx15); 
    GridBagConstraints gridBagConstraintsx16 = new GridBagConstraints(); 
    gridBagConstraintsx16.gridx = 2; 
    gridBagConstraintsx16.gridy = 6; 
    gridBagConstraintsx16.insets = new Insets(5, 5, 5, 5); 
    cPane.add(jbnFinish, gridBagConstraintsx16); 

    //jbnClear.addActionListener(this); 

    //jbnForward.addActionListener(this); 
    //jbnBack.addActionListener(this); 
    //jbnExit.addActionListener(this); 

} 
} 

這段代碼不是working.wat的錯嗎？ 該GUI包含從數據庫，完成按鈕，後退，前進button.while運行檢索數據的文本框，它並不表明我無法描繪出error.applet任何輸出 不工作

Answer 1

AddressBookDemo addrbook = new AddressBookDemo(); 
addrbook.createGUI(); 

Answer 2

更改此行：

new AddressBookDemo(); 

這樣：

new AddressBookDemo().createGUI();