connectdialog.java

这是Java编程艺术一书附带的源代码

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/* This class displays a dialog for entering e-mail
   server connection settings. */
public class ConnectDialog extends JDialog
{
  // These are the e-mail server types.
  private static final String[] TYPES = {"pop3", "imap"};

  // Combo box for e-mail server types.
  private JComboBox typeComboBox;

  // Server, username and SMTP server text fields.
  private JTextField serverTextField, usernameTextField;
  private JTextField smtpServerTextField;

  // Password text field.
  private JPasswordField passwordField;

  // Constructor for dialog.
  public ConnectDialog(Frame parent)
  {
    // Call super constructor, specifying that dialog is modal.
    super(parent, true);

    // Set dialog title.
    setTitle("Connect");

    // Handle closing events.
    addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        actionCancel();
      }
    });

    // Setup settings panel.
    JPanel settingsPanel = new JPanel();
    settingsPanel.setBorder(
      BorderFactory.createTitledBorder("Connection Settings"));
    GridBagConstraints constraints;
    GridBagLayout layout = new GridBagLayout();
    settingsPanel.setLayout(layout);
    JLabel typeLabel = new JLabel("Type:");
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.EAST;
    constraints.insets = new Insets(5, 5, 0, 0);
    layout.setConstraints(typeLabel, constraints);
    settingsPanel.add(typeLabel);
    typeComboBox = new JComboBox(TYPES);
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.WEST;
    constraints.gridwidth = GridBagConstraints.REMAINDER;
    constraints.insets = new Insets(5, 5, 0, 5);
    constraints.weightx = 1.0D;
    layout.setConstraints(typeComboBox, constraints);
    settingsPanel.add(typeComboBox);
    JLabel serverLabel = new JLabel("Server:");
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.EAST;
    constraints.insets = new Insets(5, 5, 0, 0);
    layout.setConstraints(serverLabel, constraints);
    settingsPanel.add(serverLabel);
    serverTextField = new JTextField(25);
    constraints = new GridBagConstraints();
    constraints.gridwidth = GridBagConstraints.REMAINDER;
    constraints.insets = new Insets(5, 5, 0, 5);
    constraints.weightx = 1.0D;
    layout.setConstraints(serverTextField, constraints);
    settingsPanel.add(serverTextField);
    JLabel usernameLabel = new JLabel("Username:");
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.EAST;
    constraints.insets = new Insets(5, 5, 0, 0);
    layout.setConstraints(usernameLabel, constraints);
    settingsPanel.add(usernameLabel);
    usernameTextField = new JTextField();
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.WEST;
    constraints.fill = GridBagConstraints.HORIZONTAL;
    constraints.gridwidth = GridBagConstraints.REMAINDER;
    constraints.insets = new Insets(5, 5, 0, 5);
    constraints.weightx = 1.0D;
    layout.setConstraints(usernameTextField, constraints);
    settingsPanel.add(usernameTextField);
    JLabel passwordLabel = new JLabel("Password:");
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.EAST;
    constraints.insets = new Insets(5, 5, 5, 0);
    layout.setConstraints(passwordLabel, constraints);
    settingsPanel.add(passwordLabel);
    passwordField = new JPasswordField();
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.WEST;
    constraints.fill = GridBagConstraints.HORIZONTAL;
    constraints.gridwidth = GridBagConstraints.REMAINDER;
    constraints.insets = new Insets(5, 5, 5, 5);
    constraints.weightx = 1.0D;
    layout.setConstraints(passwordField, constraints);
    settingsPanel.add(passwordField);
    JLabel smtpServerLabel = new JLabel("SMTP Server:");
    constraints = new GridBagConstraints();
    constraints.anchor = GridBagConstraints.EAST;
    constraints.insets = new Insets(5, 5, 5, 0);
    layout.setConstraints(smtpServerLabel, constraints);
    settingsPanel.add(smtpServerLabel);
    smtpServerTextField = new JTextField(25);
    constraints = new GridBagConstraints();
    constraints.gridwidth = GridBagConstraints.REMAINDER;
    constraints.insets = new Insets(5, 5, 5, 5);
    constraints.weightx = 1.0D;
    layout.setConstraints(smtpServerTextField, constraints);
    settingsPanel.add(smtpServerTextField);

    // Setup buttons panel.
    JPanel buttonsPanel = new JPanel();
    JButton connectButton = new JButton("Connect");
    connectButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        actionConnect();
      }
    });
    buttonsPanel.add(connectButton);
    JButton cancelButton = new JButton("Cancel");
    cancelButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        actionCancel();
      }
    });
    buttonsPanel.add(cancelButton);

    // Add panels to display.
    getContentPane().setLayout(new BorderLayout());
    getContentPane().add(settingsPanel, BorderLayout.CENTER);
    getContentPane().add(buttonsPanel, BorderLayout.SOUTH);

    // Size dialog to components.
    pack();

    // Center dialog over application.
    setLocationRelativeTo(parent);
  }

  // Validate connection settings and close dialog.
  private void actionConnect() {
    if (serverTextField.getText().trim().length() < 1
        || usernameTextField.getText().trim().length() < 1
        || passwordField.getPassword().length < 1
        || smtpServerTextField.getText().trim().length() < 1) {
      JOptionPane.showMessageDialog(this,
        "One or more settings is missing.",
        "Missing Setting(s)", JOptionPane.ERROR_MESSAGE);
      return;
    }

    // Close dialog.
    dispose();
  }

  // Cancel connecting and exit program.
  private void actionCancel() {
    System.exit(0);
  }

  // Get e-mail server type.
  public String getType() {
    return (String) typeComboBox.getSelectedItem();
  }

  // Get e-mail server.
  public String getServer() {
    return serverTextField.getText();
  }

  // Get e-mail username.
  public String getUsername() {
    return usernameTextField.getText();
  }

  // Get e-mail password.
  public String getPassword() {
    return new String(passwordField.getPassword());
  }

  // Get e-mail SMTP server.
  public String getSmtpServer() {
    return smtpServerTextField.getText();
  }
}