Correction: The findBestMatch method is mentioned twice in the Makeup Assignment, but with different signatures. The correct signature is static long findBestMatch(String badNumber).

Also, please note that the createDatabase(int size, long seed) method should be called from the NumberChecker(int size, long seed) constructor. To do otherwise is to risk all my JUnit tests failing, which would result in a very low grade.

Finally, this assignment asks you to use assert statements. Remember that assert statements are ignored unless you tell Java to enable them. See the Eclipse FAQ for instructions on how to enable assertions.

Because some people are not getting the expected '\012' in their text areas for newlines, I'm providing another Translator, ShowHex.java, which you can use to find out what characters really are in your text area. It will display the hexadecimal (not octal) codes for each character, plus a two- or three-letter abbreviation for the nonprinting characters (Cr for carriage return, Lf for linefeed, etc.). To use this Translator, just add it to your project (you may have to add a package declaration to it), and add the line
     addTranslateItem(new ShowHex());
to your Translator class.

In lab, I was uncertain whether text areas would automatically become scrollable when you added enough text to them.

The answer is, java.awt.TextAreas do, but javax.swing.JTextAreas don't.

To make a JTextArea behave like a TextArea, just put it inside a JScrollPane, and use the JScrollPane where you would have used the JTextArea. Like this:

    myPanel.add(new JScrollPane(myTextArea), BorderLayout.CENTER);

/**
 * Adds a KeyListener to a text field.
 * @param textField The text field.
 * @param row The row in which the text field occurs.
 * @param column The column in which the text field occurs.
 */
 private void addListener(JTextField textField, final int row, final int column) {
    textField.addKeyListener(new KeyAdapter() {
        @Override
        public void keyTyped(KeyEvent e) {
            checkValidity(row, column, e.getKeyChar());
        }
    });
}

Abdul's office hours for next week:
      Monday 3.30 pm - 4.30 pm
     Wednesday 3.30 pm - 4.30 pm

Suppose a Car class describes a car, and a Town object describes a town.

• Does a town contain a lot of vehicles, or does a car contain a lot of vehicles? (Hint: Use your common sense here.)
• Should a Town object contain an array of vehicles, or should a Car object contain an array of vehicles? (Hint: Refer to your answer to the previous question.)
• When you are displaying an array of vehicles, are you looking at a Car, or at a Town?
• When you are driving across town, do you buy a new car at every intersection, or do you just change the location of the car you are in?
• In the "real world," do cars create other cars?

Your program will be a lot easier to write if you use your knowledge of the world to decide which classes should have which variables, and what objects of each class should be able to do. Also, there is usually a "main" class--Town, in this case--which is responsible for "global" events, such as new cars being created, and displaying results.

Also, people have been asking about paint and repaint. Here's the short, easy answer: You write the paint method for cars and for ambulances, but you call my repaint method (my repaint method (in ArrayDisplay) will call your paint method for each of your Vehicles). Again: You write the paint methods, but you call my repaint method.

Here is an example program that uses ArrayDisplay. Copy this zip file to your workspace and unzip it; then from within Eclipse, File -> Import... it.