However, I am scared of this:<\/p>\n
\/**<\/span>\n * @(#)Lab02aFrame.java<\/span>\n *<\/span>\n * JFC Lab02a application<\/span>\n *<\/span>\n * @author <\/span>\n * @version 1.00 2010\/4\/21<\/span>\n *\/<\/span>\nimport java.awt.*;
\nimport java.awt.event<\/span>.*;
\nimport javax.swing.*;
\nimport javax.swing.BoxLayout;<\/p>\n
\npublic<\/span> class<\/span> Lab02aFrame extends JFrame {
\n
\n\/**<\/span>
\n * The constructor<\/span>
\n *\/<\/span>
\npublic<\/span> Lab02aFrame() {
\n
\n
\n
\nJMenuBar menuBar = new<\/span> JMenuBar();
\nJMenu menuFile = new<\/span> JMenu();
\nJMenuItem menuFileExit = new<\/span> JMenuItem();
\n
\nmenuFile.setText("File"<\/span>);
\nmenuFileExit.setText("Exit"<\/span>);
\n
\n\/\/ Add action listener.for the menu button<\/span>
\nmenuFileExit.addActionListener
\n(
\nnew<\/span> ActionListener() {
\npublic<\/span> void<\/span> actionPerformed(ActionEvent e) {
\nLab02aFrame.this<\/span>.windowClosed();
\n}
\n}
\n);
\nmenuFile.add(menuFileExit);
\nmenuBar.add(menuFile);
\n
\nsetTitle("Lab02a"<\/span>);
\nsetJMenuBar(menuBar);
\nsetSize(new<\/span> Dimension(400, 400));
\n
\nJPanel panel = new<\/span> JPanel();
\npanel.setLayout(new<\/span> BoxLayout(panel,BoxLayout.Y_AXIS));
\n
\n\/\/ test cases<\/span>
\nRectangle test = new<\/span> Rectangle();
\n
\nJLabel label1 = new<\/span> JLabel();
\ntest.setLengthWidth(2,6);
\ntest.calculatePerimeter( );
\nlabel1.setText(test.print());
\npanel.add(label1);<\/p>\n JLabel label2 = new<\/span> JLabel();
\ntest.setLengthWidth(12,5);
\ntest.calculatePerimeter( );
\nlabel2.setText(test.print());
\npanel.add(label2);
\n
\n\/\/add more test cases<\/span>
\n
\n
\nthis<\/span>.add(panel);
\n\/\/ Add window listener.<\/span>
\nthis<\/span>.addWindowListener
\n(
\nnew<\/span> WindowAdapter() {
\npublic<\/span> void<\/span> windowClosing(WindowEvent e) {
\nLab02aFrame.this<\/span>.windowClosed();
\n}
\n}
\n);
\n}
\n
\n
\n\/**<\/span>
\n * Shutdown procedure when run as an application.<\/span>
\n *\/<\/span>
\nprotected<\/span> void<\/span> windowClosed() {
\n
\n\/\/ TODO: Check if it is safe to close the application<\/span>
\n
\n\/\/ Exit application.<\/span>
\nSystem.exit(0);
\n}
\n}<\/pre>\n<\/p>\n