JTextField中添加DocumentListener事件后出现问题

Question

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class Welcome extends JFrame implements ActionListener,ChangeListener,DocumentListener
{
private JSlider inputSlider;
private JTextField inputField;
private JLabel inputLabel;
private JTextField outputField;
private JSlider outputSlider;
private JLabel outputLabel;
private void creatGUI()
{
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container window= this.getContentPane();
window.setLayout(null);
inputSlider= new JSlider(JSlider.HORIZONTAL,0,100,50);
inputSlider.setSize(new Dimension(250,20));
inputSlider.setLocation(25, 20);
inputSlider.addChangeListener(this);
window.add(inputSlider);
inputLabel= new JLabel("摄氏度:");
inputLabel.setSize(new Dimension(100,40));
inputLabel.setHorizontalAlignment(SwingConstants.CENTER);
inputLabel.setLocation(25, 50);
window.add(inputLabel);
inputField= new JTextField(Integer.toString(50));
inputField.setSize(new Dimension(100,30));
inputField.setHorizontalAlignment(SwingConstants.CENTER);
inputField.setLocation(150, 50);
inputField.getDocument().addDocumentListener(this);
window.add(inputField);
inputField.getDocument().addDocumentListener(this);
int lowTemp=(int)sheshiToHuashi(0);
int highTemp=(int)sheshiToHuashi(100)+1;
outputSlider= new JSlider(JSlider.HORIZONTAL,lowTemp,highTemp,(lowTemp+highTemp)/2);
outputSlider.setSize(new Dimension(250,20));
outputSlider.setLocation(25, 150);
outputSlider.setEnabled(false);
window.add(outputSlider);
outputLabel= new JLabel("华氏度:");
outputLabel.setSize(new Dimension(100,40));
outputLabel.setHorizontalAlignment(SwingConstants.CENTER);
outputLabel.setLocation(25, 180);
window.add(outputLabel);
outputField= new JTextField(Integer.toString((lowTemp+highTemp)/2));
outputField.setSize(new Dimension(100,30));
outputField.setHorizontalAlignment(SwingConstants.CENTER);
outputField.setLocation(150, 180);
outputField.setEditable(false);
window.add(outputField);
}
private double sheshiToHuashi(double sheshiTem)
{
return (sheshiTem*9)/5+32;
}        //实现ActionListener接口
public void actionPerformed(ActionEvent event)
{

}        //实现ChangeListener接口
public void stateChanged(ChangeEvent event)
{
int intOfSlider=inputSlider.getValue();
inputField.setText(Integer.toString(intOfSlider));
double tempOfTemp=this.sheshiToHuashi(intOfSlider);
outputSlider.setValue((int)tempOfTemp);
String tempOfTempString=String.format("%.2f", tempOfTemp);
outputField.setText(tempOfTempString);
}
        //实现DocumentListener接口
public void changedUpdate(DocumentEvent e)
{

}  
public void removeUpdate(DocumentEvent e)
{
inputSlider.setValue(0);
}
public void insertUpdate(DocumentEvent e)
{
double douOfField=Double.parseDouble(inputField.getText());
inputSlider.setValue((int)douOfField);
}
        //主函数
public static void main(String [] args)
{
Welcome frame= new Welcome();
frame.setSize(300,300);
frame.creatGUI();
frame.setVisible(true);
}
}哪位有时间的话帮我运行下这个程序，这个程序的主要问题是，inputTextField在添加DocumentListener监听之后无法正常输入文本，比如原来想输入52，但是输入之后却变成25；另外有其他什么问题还望大家可以不吝赐教下。

Answer 1

未实现DocumentListener接口时，JTextField不会出现问题

Answer 2

import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*; 
import javax.swing.event.*; 
public class Welcome extends JFrame implements ActionListener,ChangeListener,KeyListener
{ 
private JSlider inputSlider; 
private JTextField inputField; 
private JLabel inputLabel; 
private JTextField outputField; 
private JSlider outputSlider; 
private JLabel outputLabel; 
private void creatGUI() 
{ 
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
Container window= this.getContentPane(); 
window.setLayout(null); 
inputSlider= new JSlider(JSlider.HORIZONTAL,0,100,50); 
inputSlider.setSize(new Dimension(250,20)); 
inputSlider.setLocation(25, 20); 
inputSlider.addChangeListener(this); 
window.add(inputSlider); 
inputLabel= new JLabel("摄氏度:"); 
inputLabel.setSize(new Dimension(100,40)); 
inputLabel.setHorizontalAlignment(SwingConstants.CENTER); 
inputLabel.setLocation(25, 50); 
window.add(inputLabel); 
inputField= new JTextField(Integer.toString(50)); 
inputField.setSize(new Dimension(100,30)); 
inputField.setHorizontalAlignment(SwingConstants.CENTER); 
inputField.setLocation(150, 50); 
inputField.addKeyListener(this); 
window.add(inputField); 
//inputField.getDocument().addDocumentListener(this); 
int lowTemp=(int)sheshiToHuashi(0); 
int highTemp=(int)sheshiToHuashi(100)+1; 
outputSlider= new JSlider(JSlider.HORIZONTAL,lowTemp,highTemp,(lowTemp+highTemp)/2); 
outputSlider.setSize(new Dimension(250,20)); 
outputSlider.setLocation(25, 150); 
outputSlider.setEnabled(false); 
window.add(outputSlider); 
outputLabel= new JLabel("华氏度:"); 
outputLabel.setSize(new Dimension(100,40)); 
outputLabel.setHorizontalAlignment(SwingConstants.CENTER); 
outputLabel.setLocation(25, 180); 
window.add(outputLabel); 
outputField= new JTextField(Integer.toString((lowTemp+highTemp)/2)); 
outputField.setSize(new Dimension(100,30)); 
outputField.setHorizontalAlignment(SwingConstants.CENTER); 
outputField.setLocation(150, 180); 
outputField.setEditable(false); 
window.add(outputField); 
} 
private double sheshiToHuashi(double sheshiTem) 
{ 
return (sheshiTem*9)/5+32; 
} 

        //实现ActionListener接口 
public void actionPerformed(ActionEvent event) 
{ 

} 

        //实现ChangeListener接口 
public void stateChanged(ChangeEvent event) 
{ 
int intOfSlider=inputSlider.getValue(); 
inputField.setText(Integer.toString(intOfSlider)); 
double tempOfTemp=this.sheshiToHuashi(intOfSlider); 
outputSlider.setValue((int)tempOfTemp); 
String tempOfTempString=String.format("%.2f", tempOfTemp); 
outputField.setText(tempOfTempString); 
} 
/*
        //实现DocumentListener接口 
public void changedUpdate(DocumentEvent e) 
{ 

}  
public void removeUpdate(DocumentEvent e) 
{ 
inputSlider.setValue(0); 
} 
public void insertUpdate(DocumentEvent e) 
{ 
double douOfField=Double.parseDouble(inputField.getText()); 
inputSlider.setValue((int)douOfField); 
} */

//实现KeyListener接口
public void keyTyped(KeyEvent e)
{
double douOfField=Double.parseDouble(inputField.getText()); 
inputSlider.setValue((int)douOfField); 
}
public void keyPressed(KeyEvent e)
{ 
double douOfField=Double.parseDouble(inputField.getText()); 
inputSlider.setValue((int)douOfField); 
} 
public void keyReleased(KeyEvent e)
{ 
double douOfField=Double.parseDouble(inputField.getText()); 
inputSlider.setValue((int)douOfField); 
} 

        //主函数 
public static void main(String [] args) 
{ 
Welcome frame= new Welcome(); 
frame.setSize(300,300); 
frame.creatGUI(); 
frame.setVisible(true); 
} 
} 若输入文本框被删至为空后会出错，如果不采用异常处理应该怎么办？？