PassGen

/**
 Made by Classified; GUI by mjau.
 */
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class GenerateOne extends JFrame implements ActionListener {
  public static int MIN_LENGTH;
  protected static java.util.Random r = new java.util.Random();
  protected static char[] goodChar = { 'a', 'b', 'c', 'd', 'e', 'f', 'g',
      'h', 'j', 'k', 'm', 'n', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w',
      'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K',
      'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
      '2', '3', '4', '5', '6', '7', '8', '9', };
  JTextField amount = new JTextField(2);
  JButton generate = new JButton("Generate");
  JLabel length = new JLabel("Length: ");
  String lengthString;
  JTextField outField = new JTextField(15);
  public GenerateOne() {
      super("PassGen");
      setSize(200, 200);
      amount.addActionListener(this);
      generate.addActionListener(this);
          GridBagLayout gridbag = new GridBagLayout();
          GridBagConstraints constraints = new GridBagConstraints();
      setLayout(gridbag);
      constraints.weighty = 3;
      constraints.anchor = GridBagConstraints.EAST;
      constraints.gridwidth = 1;
      gridbag.setConstraints(length, constraints);
      add(length);
      constraints = new GridBagConstraints();
      constraints.gridx = 1;
      constraints.gridwidth = 2;
      constraints.weighty = 3;
      constraints.anchor = GridBagConstraints.CENTER;
      gridbag.setConstraints(amount, constraints);
      add(amount);
      constraints = new GridBagConstraints();
      constraints.gridx = 0;
      constraints.gridy = 1;
      constraints.gridwidth = 3;
      constraints.weighty = 3;
      gridbag.setConstraints(generate, constraints);
      add(generate);
      constraints.gridy = 2;
      constraints.gridwidth = 3;
      constraints.weighty = 3;
      gridbag.setConstraints(outField, constraints);
      add(outField);
      outField.setEditable(false);


  }
  public static String getNext() {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < MIN_LENGTH; i++) {
          sb.append(goodChar[r.nextInt(goodChar.length)]);
        }
        return sb.toString();
  }
  public void actionPerformed(ActionEvent evt) {
      Object source = evt.getSource();
      if (source == generate) {
          lengthString = amount.getText();
          try {
              MIN_LENGTH = Integer.parseInt(lengthString);
          } catch (Exception e) {
              JOptionPane.showMessageDialog(null, "Please enter a correct value!");
              System.err.println(e);
          }
          outField.setText(GenerateOne.getNext());
      }


}

  public static void main(String[] args) {

    GenerateOne frame = new GenerateOne();
    frame.setVisible(true);
  }
}