converter.java

编译一个窗口

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



public class Converter extends JFrame implements ActionListener{
	private JLabel toB;
	private JLabel toD;
	private JTextField txtB;
	private JTextField txtD;
	private JButton btntoB;
	private JButton btntoD;
	private JButton btnclear;
	public Converter(){
		
		createComponents();
		layoutComponents();
		setTitle("Converter");
		setDefaultCloseOperation(EXIT_ON_CLOSE);
		pack();
		
	}
	private void createComponents(){
		setLocation(250,250);
		toB=new JLabel("二进制数");
		toD=new JLabel("十进制数");
		txtB=new JTextField(20);
		txtD=new JTextField(20);
		btntoB=new JButton("转二进制");
		btntoB.addActionListener(this);
		btntoD=new JButton("转十进制");	
		btntoD.addActionListener(this);
		btnclear=new JButton("清除");
		btnclear.addActionListener(this);
	
	}
	private void layoutComponents(){
		Container c=this.getContentPane();
		c.setLayout(new GridLayout(3,1));
		JPanel toBPane=new JPanel(new FlowLayout(FlowLayout.LEFT));
		toBPane.add(toB);
		toBPane.add(txtB);
		JPanel toDPane=new JPanel(new FlowLayout(FlowLayout.LEFT));
		toDPane.add(toD);
		toDPane.add(txtD);
		JPanel btnPane=new JPanel(new FlowLayout());
		btnPane.add(btntoB);
		btnPane.add(btntoD);
		btnPane.add(btnclear);
		c.add(toBPane);		
		c.add(toDPane);
		c.add(btnPane);
		
}
	
	public void actionPerformed(ActionEvent a) { 
		String str1 = a.getActionCommand();
	    if (str1.equals("转二进制")) {
	      String str2 = this.txtD.getText();
	      try
	      {
	        int i = Integer.parseInt(str2);
	       String str4= Integer.toBinaryString(i) ;
           this.txtB.setText(str4);
           
	      } catch (NumberFormatException localNumberFormatException) {
	    	  this.txtB.setText("Illegal Input!!"); }}
	      else if (str1.equals("清除")) {
	          this.txtD.setText("");
	          this.txtB.setText("");
	        }
	      else if (str1.equals("转十进制")){
	    	  String str2 = this.txtB.getText();
	    	  
	    	 try {
				String str3= Integer.valueOf(str2,2).toString() ;
				  this.txtD.setText(str3);
			} catch (NumberFormatException localNumberFormatException) {
			    	  this.txtD.setText("Illegal Input!!"); 
				
			}
			}
	    			  
	    	  
	      }
	               

	
	public static void main (String[] args){
		JFrame.setDefaultLookAndFeelDecorated(true);
		Converter converter=new Converter();
		converter.setVisible(true);
		}
	
	
}