java如何实现登录窗口

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登录窗口主类

package ccnu.paint;import java.awt.Color;import java.awt.Font;import java.awt.GridLayout;import java.awt.Point;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.util.Enumeration;import java.util.Properties;import javax.swing.ImageIcon;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JPasswordField;import javax.swing.JTextField;import ccnu.util.Answer;import ccnu.util.Verification;public class Login extends JFrame{    private static final long serialVersionUID = 1L;    private Properties pro = new Properties();    private boolean ver_code = false; // 默认输入验证码错误    private Answer answer = null;    private JPanel p1 = new JPanel(); // 添加到JPanel中的组件默认为流式布局    private JLabel luser = new JLabel("username: ");    private JTextField username = new JTextField(20);    private JPanel p2 = new JPanel();    private JLabel lpwd = new JLabel("password: ");    private JPasswordField pwd = new JPasswordField(20);    private JPanel p4 = new JPanel();    private JLabel lVer = new JLabel("verification: ");    private JTextField ver = new JTextField(10);    private JLabel img = new JLabel();    private JLabel result = new JLabel();    private JPanel p3 = new JPanel();    private JButton ok = new JButton("ok");    private JButton cancel = new JButton("cancel");    private JButton signUp = new JButton("Sign up"); // 用于账户注册    // 设置组件的监听    public void initListener()    {        username.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e)            {// JTextField的action是回车键                String name = username.getText();                // Login.this.setTitle(name);                // System.out.println(name.hashCode() + "***" +"".hashCode());                if (name.equals(""))                {                    JOptionPane.showMessageDialog(Login.this, "Please input a userName!");                } else                {                    pwd.grabFocus();                }            }        });        pwd.addActionListener(new ActionListener(){            @Override            public void actionPerformed(ActionEvent e)            {                String password = new String(pwd.getPassword());                if(password.equalsIgnoreCase(""))                {                    JOptionPane.showMessageDialog(Login.this, "please input a password!");                }else{                    ver.grabFocus();                }            }        });        ok.addActionListener(new ActionListener(){            @Override            public void actionPerformed(ActionEvent e)            {                // 重新加载最新的账户文件                try                {                    pro.load(new FileInputStream(new File("src/res/accouts.properties")));                } catch (IOException e1)                {                    e1.printStackTrace();                }                check();            }        });        // 判断验证码是否正确        ver.addActionListener(new ActionListener(){            @Override            public void actionPerformed(ActionEvent e)            {                String verCode = ver.getText();                if(verCode.equals(""))                {                    JOptionPane.showMessageDialog(Login.this, "Please input a verification!");                }else{                    if(verCode.equals(answer.getResult()))                    {                        result.setIcon(new ImageIcon(Login.this.getClass().getResource("/res/right.jpg"))); // 显示提示的图片信息(如√图片)                        ver_code = true;                        // 检查之前，重新加载最新的账户文件                        try                        {                            pro.load(new FileInputStream(new File("src/res/accouts.properties"))); // 将账户文件加载进来                        } catch (IOException e1)                        {                            e1.printStackTrace();                        }                        check();                    }else{                        result.setIcon(new ImageIcon(Login.this.getClass().getResource("/res/error.jpg"))); // 显示提示的图片信息(如×图片)                         ver_code = false;                    }                }            }        });        // 点击图片会更改验证码        img.addMouseListener(new MouseAdapter(){            @Override            public void mouseClicked(MouseEvent e)            {                answer = Verification.verification();                img.setIcon(new ImageIcon(answer.getBufferedImage())); // 设置验证码图案            }        });        cancel.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e)            {                int option = JOptionPane.showConfirmDialog(Login.this, "Are you sure to exit?");//              System.out.println("option = " + option);                if (option == 0)                {// Yes                    Login.this.dispose();                }            }        });        signUp.addActionListener(new ActionListener(){            @Override            public void actionPerformed(ActionEvent e)            {                new SignUp();            }        });    }    // 初始化登录窗口及其组件的设置监听    public Login()    {        super("Login");        // 加载账户文件        try        {            pro.load(new FileInputStream(new File("src/res/accouts.properties"))); // 从指定位置将账户文件加载进来        } catch (IOException e)        {            e.printStackTrace();        }        initListener();        answer = Verification.verification(); // 生成验证码        img.setIcon(new ImageIcon(answer.getBufferedImage())); // 设置初始验证码        this.setLocation(new Point(200, 200));        this.setSize(500, 300);        this.setLayout(new GridLayout(4, 1, 0, 20)); // 垂直间隙为20px        p1.add(luser);        p1.add(username);        p2.add(lpwd);        p2.add(pwd);        p4.add(this.lVer);        p4.add(this.ver);        p4.add(this.img);        result.setForeground(Color.red);        result.setFont(new Font("楷体", Font.BOLD, 20));        p4.add(result);        p3.add(ok);        p3.add(cancel);        p3.add(signUp);        this.add(p1);        this.add(p2);            this.add(p4);        this.add(p3);//      this.setBackground(Color.blue); // JFrame的上层还有一个ContentPane        this.getContentPane().setBackground(Color.gray);        this.setResizable(false);        this.setVisible(true);        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // 等价于Frame中的windowClosing事件    }    // 检查用户名或密码    public void check()    {        String verCode = ver.getText();        if(verCode.equals(""))        {            JOptionPane.showMessageDialog(Login.this, "Please input a verification!");            return;        }else{            if(verCode.equals(answer.getResult()))            {                result.setIcon(new ImageIcon(Login.this.getClass().getResource("/res/right.jpg")));                ver_code = true;            }else{                result.setIcon(new ImageIcon(Login.this.getClass().getResource("/res/error.jpg")));                ver_code = false;            }        }        if(ver_code == false)        {            JOptionPane.showMessageDialog(this, "verification is error!");            return;        }        String name = username.getText();        String password = new String(pwd.getPassword()); // return char[]//      if (name.equalsIgnoreCase("admin") && password.equals("123456"))        if (isPass(name, password))        {//          new PaintApp(name);            JOptionPane.showMessageDialog(this, "-^_^-   OK..."); // 此处可以加上其他的登陆成功后进一步处理的窗口            this.dispose();        } else        {            JOptionPane.showMessageDialog(this, "userName or password is incorrect!");            username.setText("");            pwd.setText("");            ver.setText("");            answer = Verification.verification();            img.setIcon(new ImageIcon(answer.getBufferedImage()));            result.setIcon(null);        }    }    // 验证用户输入的账户名和密码是否正确(通过与加载进来的账户 pro 比对)    public boolean isPass(String name, String password)    {        Enumeration en = pro.propertyNames();        while(en.hasMoreElements())        {            String curName = (String)en.nextElement();//          System.out.println(curName + "---" + pro.getProperty(curName));            if(curName.equalsIgnoreCase(name))            {                if(password.equalsIgnoreCase(pro.getProperty(curName)))                {                    return true;                }            }        }        return false;    }    public static void main(String[] args)    {        new Login();    }}

账户注册类

package ccnu.paint;import java.awt.GridLayout;import java.awt.Point;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.util.Enumeration;import java.util.Properties;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JPasswordField;import javax.swing.JTextField;public class SignUp extends JFrame{    private static final long serialVersionUID = 3054293481122038909L;    private Properties pro = new Properties(); // 最好时静态的，因为账户是共享的    private JPanel panel = new JPanel();    private JLabel label = new JLabel("username: ");    private JTextField field = new JTextField(15);    private JPanel panel2 = new JPanel();    private JLabel label2 = new JLabel("password: ");    private JPasswordField field2 = new JPasswordField(15);    private JPanel panel3 = new JPanel();    private JLabel label3 = new JLabel("confirmation: ");    private JPasswordField field3 = new JPasswordField(15);    private JPanel panel4 = new JPanel();    private JButton button = new JButton("OK");    private JButton button2 = new JButton("Cancel");    public void initListener()    {        field.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e)            {                field2.grabFocus();            }        });        field2.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e)            {                field3.grabFocus();            }        });        field3.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e)            {                ok_actionPerformed(e);            }        });        // OK        button.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e)            {                ok_actionPerformed(e);            }        });        // Cancel        button2.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e)            {                cancel_actionPerformed(e);            }        });    }    public void ok_actionPerformed(ActionEvent e)    {        String userName = field.getText();        String password = new String(field2.getPassword());        String password2 = new String(field3.getPassword());        if (userName.equals(""))        {            JOptionPane.showMessageDialog(SignUp.this, "username cannot be empty!");        } else        {            if (password.equalsIgnoreCase(""))            {                JOptionPane.showMessageDialog(SignUp.this, "password cannot be empty!");            } else            {                if (password2.equalsIgnoreCase(password))                {                    if (isExist(userName))                    {                        JOptionPane.showMessageDialog(SignUp.this, "username has been existed!");                        field.setText("");                        field2.setText("");                        field3.setText("");                    } else                    {                        pro.setProperty(userName, password);                        JOptionPane.showMessageDialog(SignUp.this, "SignUp success!");                        writeToPro(userName, password); // 将其写入到账户文件中                        SignUp.this.dispose();                    }                } else                {                    JOptionPane.showMessageDialog(SignUp.this, "password is not consistent!");                    field2.setText("");                    field3.setText("");                }            }        }    }    public void cancel_actionPerformed(ActionEvent e)    {        System.exit(0);    }    public SignUp()    {        super("Sign up");        // 加载账户文件        try        {            pro.load(new FileInputStream(new File("src/res/accouts.properties")));        } catch (IOException e)        {            e.printStackTrace();        }        // 初始化窗口组件的监听        initListener();        this.setLocation(new Point(300, 230));        this.setSize(280, 210);        this.setLayout(new GridLayout(4, 1, 0, 20)); // 垂直间隙为20px        panel.add(label);        panel.add(field);        panel2.add(label2);        panel2.add(field2);        panel3.add(label3);        panel3.add(field3);        panel4.add(button);        panel4.add(button2);        this.add(panel);        this.add(panel2);        this.add(panel3);        this.add(panel4);        this.setAlwaysOnTop(true);        this.setResizable(false);        this.setVisible(true);    }    // 如果注册始终可用,就要保存起来，否则不需要写入文件中，注册账户本次使用    // 将账户名与其对应密码保存到指定的账户文件中    public void writeToPro(String userName, String password)    {        pro.setProperty(userName, password);        try        {            pro.store(new FileOutputStream(new File("src/res/accouts.properties")), "allAccouts");        } catch (IOException e)        {            e.printStackTrace();        }    }    // 判断此用户名是否已经存在    public boolean isExist(String userName)    {        Enumeration enumer = pro.propertyNames();        while (enumer.hasMoreElements())        {            String temp = (String) enumer.nextElement();            if (temp.equals(userName))            {                return true;            }        }        return false;    }}

生成验证码类

package ccnu.util;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.Point;import java.awt.image.BufferedImage;import java.util.Random;// 用于生成验证码public class Verification{    private static Answer answer = new Answer();    private static BufferedImage bufferedImage = null;    private static String result = null;    private static String words = null;    private static String words2 = null;    // 生成验证码    public static Answer verification()    {        bufferedImage = new BufferedImage(200, 35, BufferedImage.TYPE_INT_RGB);        Graphics g = bufferedImage.getGraphics();        Random rand = new Random();        for (int i = 0; i < 20; i++)        {            Point p1 = new Point(rand.nextInt(200), rand.nextInt(30));            Point p2 = new Point(rand.nextInt(200), rand.nextInt(30));            g.drawLine(p1.x, p1.y, p2.x, p2.y);        }        g.setColor(Color.RED);        g.setFont(new Font("楷体", Font.BOLD, 22));        int plan = 2;        switch (rand.nextInt(plan))        {        case 0:            plan(g);            break;        case 1:            plan1(g);            break;        default:            break;        }        answer.setBufferedImage(bufferedImage);        answer.setResult(result);        g.dispose();        return answer;    }    // 方案一    private static void plan(Graphics g)    {        words = ReadTxt.read("/res/words.txt"); // 指定生成验证码问题的资源文件的路径        Random rand = new Random();        String first = String.valueOf(words.charAt(rand.nextInt(words.length())));        String second = String.valueOf(words.charAt(rand.nextInt(words.length())));        String third = String.valueOf(words.charAt(rand.nextInt(words.length())));        g.drawString(first, rand.nextInt(40) + 20, rand.nextInt(12) + 15);        g.drawString(second, rand.nextInt(40) + 80, rand.nextInt(12) + 15);        g.drawString(third, rand.nextInt(40) + 140, rand.nextInt(12) + 15);        result = first + second + third;    }    // 方案二    private static void plan1(Graphics g)    {        words2 = ReadTxt.read("/res/words2.txt"); // 指定生成验证码问题的资源文件的路径        Random rand = new Random();        String first = String.valueOf(words2.charAt(rand.nextInt(words2.length() - 2)));        String second = String.valueOf(words2.charAt(rand.nextInt(2) + 9));        String third = String.valueOf(words2.charAt(rand.nextInt(words2.length() - 2)));        g.drawString(first, rand.nextInt(30) + 20, rand.nextInt(12) + 15);        g.drawString(second, rand.nextInt(40) + 60, rand.nextInt(12) + 15);        g.drawString(third, rand.nextInt(30) + 110, rand.nextInt(12) + 15);        g.drawString("=", rand.nextInt(40) + 150, rand.nextInt(12) + 15);        if(second.equals("+"))        {            result = String.valueOf(Integer.valueOf(first) + Integer.valueOf(third));         }else{            result = String.valueOf(Integer.valueOf(first) - Integer.valueOf(third));         }    }}

读取生成验证码所需文件类

package ccnu.util;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;// 专门用于读取文件public class ReadTxt{    public static String read(String path) // 根据指定路径path来读取它，并返回它所包含的内容    {        StringBuffer sb = new StringBuffer();        try        {            BufferedReader br = new BufferedReader(new InputStreamReader(Verification.class.getResourceAsStream(path)));            String temp = null;            while(null != (temp = br.readLine()))            {                sb.append(temp);            }            br.close();        } catch (IOException e)        {            e.printStackTrace();        }        return sb.toString();    }}

得到生成的验证码所包含的信息类(图案、问题)

package ccnu.util;import java.awt.image.BufferedImage;// 用于将生成的验证码的图案信息以及问题结果封装public class Answer{    private BufferedImage bufferedImage = null; // 验证码图像    private String result = null; // 验证码图像问题的答案    public BufferedImage getBufferedImage()    {        return bufferedImage;    }    public void setBufferedImage(BufferedImage bufferedImage)    {        this.bufferedImage = bufferedImage;    }    public String getResult()    {        return result;    }    public void setResult(String result)    {        this.result = result;    }}

验证码生成汉字识别的问题的文件words.txt
如： 中国湖北省武汉市汉东大学政法学院

验证码生成算术运算的问题的文件words2.txt
123456789+-

提示图片

登录效果

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