字符串生成器

今天把CDKEY生成器给完善了一下，增加了大写字母，小写字母，数字多选择性生成。

package randomString;

import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.StringSelection;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;

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

public class RandomString {
    /** 
     * 生成随机字符串
     */  
    private JFrame jFrame;  
    private JPanel jp;  
    private JButton jb;  
    private JTextField tf,tf2;  
    private JLabel  jl;
    private JCheckBox cb1;
    private JCheckBox cb2;
    private JCheckBox cb3;
    private Toolkit toolkit;
    private Clipboard clipboard;		//clipboard.setContents(Transferable contents, ClipboardOwner owner);
    private StringSelection stringSel;	//实现传输 String 所需能力的 Transferable
    private int model;
    public RandomString(){  
        jFrame = new JFrame("字符串生成工具  by:毛兴宇");  
        jp = new JPanel();  
        jb = new JButton("生成(s)");  
        tf = new JTextField(20);  
        tf2 = new JTextField("10",3);  
        jl = new JLabel("位");
        cb1 = new JCheckBox("大写字母",true);
        cb2 = new JCheckBox("小写字母",true);
        cb3 = new JCheckBox("数字",true);
        toolkit = Toolkit.getDefaultToolkit();//获得工具包
        clipboard = toolkit.getSystemClipboard();//获得系统剪贴板
        MyActionListener mal = new MyActionListener();  //监听器定义
        JCheckBox jcb[]={cb1,cb2,cb3};
        
        //UI添加
        for (int i = 0; i < jcb.length; i++) {
			jp.add(jcb[i]);
		}
        jp.add(tf);  
        jp.add(jb);  
        jp.add(tf2);  
        jp.add(jl);
        jFrame.add(jp);  
        
        //快捷键设置ALT+S
        jb.setMnemonic('s'); 
        
        //添加监听器
        jb.addActionListener(mal);  
        for (int i = 0; i < jcb.length; i++) {
			jcb[i].addActionListener(mal);
		}
        
        //UI显示 
        jFrame.pack();  
        int w = jFrame.getToolkit().getScreenSize().width;//宽度  
        int h = jFrame.getToolkit().getScreenSize().height;//高度  
        jFrame.setLocation(w/2-301,h/2-36);  
        jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
        jFrame.setVisible(true);  
    }  
    class MyActionListener implements ActionListener{  
        @Override  
        public void actionPerformed(ActionEvent e) {  
            if(e.getSource().equals(jb)){  
                try {  
                	//获取JCheckBox的值,判断并调用字符串.
                	if(cb1.isSelected() == true && cb2.isSelected() == true && cb3.isSelected() == true)
                	{
                		model = 1;
                	}else if (cb2.isSelected() == true && cb3.isSelected() == true) 
                	{
						model = 2;
					}else if (cb1.isSelected() == true && cb3.isSelected() == true) 
					{
						model = 3;
					}else if (cb1.isSelected() == true && cb2.isSelected() == true)
					{
						model = 4;
					}else if (cb3.isSelected() == true)
					{
						model = 5;
					}else if (cb2.isSelected() == true)
					{
						model = 6;
					}else if (cb1.isSelected() == true)
					{
						model = 7;
					}
                
                	//设置JTextField文字显示,并保存字符串到系统剪贴板.
                    tf.setText(RandomString.getRandomString(Integer.parseInt(tf2.getText()), model));
                    stringSel = new StringSelection(tf.getText());
                    clipboard.setContents(stringSel, null);
                } catch (Exception x) {  
                    JOptionPane.showMessageDialog(null, "请输入数字");  
                }  
            }  
        }  
    }
    public static String getRandomString(int length,int model) { //length表示生成字符串的长度  
        String base1 = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        String base2 = "abcdefghijklmnopqrstuvwxyz";
        String base3 = "0123456789";
        //根据model设置字符串由哪些组成.
        Random random = new Random();
        String base = new String();
        if(model == 1)
        {
        	base = base1 + base2 + base3;
        }else if (model == 2) {
			base = base2 + base3;
		}else if (model == 3) {
			base = base1 + base3;
		}else if (model == 4) {
			base = base1 + base2;
		}else if (model == 5) {
			base = base3;
		}else if (model == 6) {
			base = base2;
		}else if (model == 7) {
			base = base1;
		}
        StringBuffer sb = new StringBuffer();     
        for (int i = 0; i < length; i++) {     
            int number = random.nextInt(base.length());     
            sb.append(base.charAt(number));     
        }     
        return sb.toString();  
    }   
	public static void main(String[] args) {
		
		 new RandomString();  
	}

}