TestFrame.java

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.charset.Charset;

import javax.swing.JButton;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;

public class TestFrame extends JFrame implements ActionListener {

	private JPanel contentPane;

	private JButton btnOpenFile;
	private JScrollPane scrollPane;
	private JTextArea textArea;
	private JFileChooser fc;
	private JMenuBar menuBar;
	private JMenu mnFile;
	private JMenu mnSettings;
	private JMenu mnPort;
	private JMenu mnHelp;
	private JMenuItem mntmAbout;
	private JButton btnAddPort;
	private JButton btnRemovePort;
	private JButton btnClearPorts;

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					TestFrame frame = new TestFrame();
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}

	/**
	 * Create the frame.
	 */
	public TestFrame() {
		try {
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
		} catch (ClassNotFoundException | InstantiationException
				| IllegalAccessException | UnsupportedLookAndFeelException e2) {
			// TODO Auto-generated catch block
			e2.printStackTrace();
		}

		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 450, 300);

		menuBar = new JMenuBar();
		setJMenuBar(menuBar);

		mnFile = new JMenu("File");
		menuBar.add(mnFile);

		mnSettings = new JMenu("Settings");
		menuBar.add(mnSettings);

		mnPort = new JMenu("Port");
		mnSettings.add(mnPort);

		mnHelp = new JMenu("?");
		menuBar.add(mnHelp);

		mntmAbout = new JMenuItem("About");
		mnHelp.add(mntmAbout);
		contentPane = new JPanel();
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
		setContentPane(contentPane);
		contentPane.setLayout(new BorderLayout(0, 0));

		JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
		contentPane.add(tabbedPane);

		JPanel pOpen = new JPanel();
		tabbedPane.addTab("Open", null, pOpen, null);
		pOpen.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));

		fc = new JFileChooser();
		btnOpenFile = new JButton("Open File...");
		btnOpenFile.addActionListener(this);
		pOpen.add(this.btnOpenFile);

		btnAddPort = new JButton("Add Port");
		btnAddPort.addActionListener(this);
		pOpen.add(btnAddPort);

		btnRemovePort = new JButton("RemovePort");
		btnRemovePort.addActionListener(this);
		pOpen.add(btnRemovePort);

		btnClearPorts = new JButton("Clear Ports");
		btnClearPorts.addActionListener(this);
		pOpen.add(btnClearPorts);

		this.textArea = new JTextArea();
		this.textArea.setEditable(false);

		this.scrollPane = new JScrollPane(this.textArea);
		tabbedPane.addTab("View", null, scrollPane, null);
	}

	private static String readFile(File file) throws IOException {
		FileInputStream stream = new FileInputStream(file);
		try {
			FileChannel fc = stream.getChannel();
			MappedByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0,
					fc.size());
			/* Instead of using default, pass in a decoder. */
			return Charset.defaultCharset().decode(bb).toString();
		} finally {
			stream.close();
		}
	}

	@Override
	public void actionPerformed(ActionEvent e) {
		// open file:
		if (e.getSource() == btnOpenFile) {
			int returnVal = fc.showOpenDialog(this);

			String content = "";
			if (returnVal == JFileChooser.APPROVE_OPTION) {
				File file = fc.getSelectedFile();
				try {
					content = TestFrame.readFile(file);
				} catch (IOException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				}
			} else {
				// nothing to do here...
			}

			textArea.setText(content);
			textArea.setCaretPosition(0);
			// add port
		} else if (e.getSource() == btnAddPort) {
			System.out.println("adding port");
			mnPort.add(new JCheckBoxMenuItem("New Port " + mnPort.getComponentCount()));
			// remove port
		} else if (e.getSource() == btnRemovePort) {
			System.out.println("removing port");
			mnPort.remove((mnPort.getComponentCount() - 1));
			// clear ports
		} else if (e.getSource() == btnClearPorts) {
			System.out.println("clearing ports");
			mnPort.removeAll();
		}
	}
}