MD5 Encrypter - MD5GUI.java

/*
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 * and open the template in the editor.
 */
package md5;

/**
 *
 * @author thieumao
 */
import java.awt.Button;
import java.awt.Component;
import java.awt.Desktop;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Label;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.math.BigInteger;
import java.net.URI;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;

public class MD5GUI extends JFrame implements ActionListener {

    private GridBagLayout gb;
    private GridBagConstraints gbc;
    private Label lbForm, lbUser, lbPass;
    private TextField tfUser, tfPass;
    private Button btRegister, btCancel;
    JMenuBar mymbar;
    JMenu jmFile, jmHelp;

    public static String encryptMD5(String input) {
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] messageDigest = md.digest(input.getBytes());
            BigInteger number = new BigInteger(1, messageDigest);
            String hashtext = number.toString(16);
            while (hashtext.length() < 32) {
                hashtext = "0" + hashtext;
            }
            return hashtext;
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        }
    }

    public void Them(Component comp, int x, int y, int rong, int cao) {
        gbc = new GridBagConstraints();
        gbc.gridx = x;
        gbc.gridy = y;
        gbc.gridwidth = rong;
        gbc.gridheight = cao;
        gb.setConstraints(comp, gbc);
        this.add(comp);
    }

    public MD5GUI(String title) {
        super(title);
        this.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent we) {
                System.exit(0);
            }
        });

        mymbar = new JMenuBar();
        jmFile = new JMenu("File");
        JMenuItem exit = new JMenuItem("Exit");
        exit.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
        });
        jmFile.add(exit);
        mymbar.add(jmFile);

        jmHelp = new JMenu("Help");
        JMenuItem creator = new JMenuItem("Author");
        creator.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(null, "Author: Thieu Mao - KSEC");
            }
        });
        JMenuItem instruction = new JMenuItem("Website");
        instruction.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                Desktop desktop = Desktop.getDesktop();
                try {
                    desktop.browse(new URI("http://thieumao.blogspot.com/"));
                } catch (Exception ex) {
                    System.out.println("Error!");
                }
            }
        });
        jmHelp.add(creator);
        jmHelp.addSeparator();
        jmHelp.add(instruction);
        mymbar.add(jmHelp);

        setJMenuBar(mymbar);


        lbForm = new Label("MD5 Encrypter");
        lbUser = new Label("Text:");
        lbPass = new Label("MD5:");
        tfUser = new TextField(35);
        tfPass = new TextField(35);
        tfPass.disable();
        btRegister = new Button("Calculate");
        btCancel = new Button("Clear");

        gb = new GridBagLayout();
        this.setLayout(gb);
        Them(lbForm, 1, 0, 2, 1);
        Them(lbUser, 0, 1, 1, 1);
        Them(tfUser, 1, 1, 2, 1);
        Them(lbPass, 0, 2, 1, 1);
        Them(tfPass, 1, 2, 2, 1);
        Them(btRegister, 1, 3, 1, 1);
        Them(btCancel, 2, 3, 1, 1);

        btRegister.addActionListener(this);
        btCancel.addActionListener(this);
    }

    public static void main(String[] args) throws Exception {
        MD5GUI fr = new MD5GUI("MD5 Encrypter - Thieu Mao");
        fr.setSize(440, 200);
        fr.setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent ae) {
        if (ae.getSource() == btRegister) {
            tfPass.setText(encryptMD5(tfUser.getText()));
        }
        if (ae.getSource() == btCancel) {
            tfUser.setText("");
            tfPass.setText("");
        }
    }
}