//要求如下/**如何在程序中UserFrame構(gòu)造方法中第一行彈出一個(gè)類似的對(duì)話框，*其中有兩個(gè)輸入框，分別輸入用戶名和密碼，可以返回兩個(gè)String*而不采用如下split方法來(lái)分別驗(yàn)證用戶名和密碼？*我曾試圖自己寫一個(gè)對(duì)話框，但是程序在彈出對(duì)話框后沒有暫停執(zhí)行等待輸入，*而是，即使不輸入正確的用戶名和密碼，也會(huì)彈出UserFrame，代碼如下：*/import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JOptionPane;import javax.swing.JPanel;public class UserFrame extends JFrame {public UserFrame() {// 即以下此行中是否有現(xiàn)成寫好的類可以顯示一個(gè)對(duì)話框，有兩個(gè)輸入框String str = JOptionPane.showInputDialog(this, new String[] {"Please input username", "password" }, "login",DO_NOTHING_ON_CLOSE);String username = null;String password = null;try {if (str == null || "".equals(str.trim())) {System.out.println("no input");System.exit(0);}String[] info = str.split(",");username = info[0];password = info[1];} catch (Exception e) {System.exit(0);}if (username.equals("scott") && password.equals("tiger")) {this.setContentPane(getContent());this.setBounds(250, 100, 600, 480);this.setTitle("UI");this.setResizable(false);this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);} else {System.exit(0);}}public JPanel getContent() {JPanel panel = new JPanel();JButton button = new JButton("doSomething");button.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent e) {System.out.println("doSomething");}});panel.add(button);return panel;}public final static void main(String[] args) {UserFrame uf = new UserFrame();uf.setVisible(true);}}如何寫？