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    <p>First, I would create a class <code>InputData</code> that would store the inputs from the user:</p> <pre><code>class InputData { public int number1; public int number2; public int number3; } </code></pre> <p>This in itself is a useful general technique: collect several related values into a single data structure. You can then either rewrite your <code>main</code> method to use this class instead of three separate <code>int</code> variables, or you can go one step further and add some behavior to the <code>InputData</code> class. The obvious first behavior to add would be to compute the average:</p> <pre><code>class InputData { public int number1; public int number2; public int number3; public int average() { return (number1 + number2 + number3) / 3; } } </code></pre> <p>With this, you could rewrite your <code>main</code> as follows:</p> <pre><code>public class Average3 { static class InputData { public int number1; public int number2; public int number3; public int average() { return (number1 + number2 + number3) / 3; } } /** * @param args */ public static void main(String[] args) { InputData input = new InputData(); System.out.println("Enter the first integer."); Scanner keyboard = new Scanner(System.in); input.number1 = keyboard.nextInt(); System.out.println("Enter the second integer."); input.number2 = keyboard.nextInt(); System.out.println("Enter the third integer."); input.number3 = keyboard.nextInt(); System.out.println("The average of NUMBER1, NUMBER2, and NUMBER3 = " + input.average()); } } </code></pre> <p>Notice that I've made <code>InputData</code> a <a href="http://docs.oracle.com/javase/tutorial/java/javaOO/nested.html" rel="nofollow"><em>static inner class</em></a> of <code>Average3</code>. It could also have been a separate, top-level class in the same file (as long as it wasn't <code>public</code>) or a class in a separate file.</p> <p>An improvement on this would be to use an array instead of separate <code>int</code> fields in the <code>InputData</code> class. Your program might then look like this:</p> <pre><code>public class Average3 { static class InputData { public int[] numbers; InputData(int size) { numbers = new int[size]; } public int average() { int sum = 0; for (int number : numbers) { sum += number; } return sum / numbers.length; } } /** * @param args */ public static void main(String[] args) { String[] prompts = { "first", "second", "third" }; InputData input = new InputData(3); Scanner keyboard = new Scanner(System.in); for (int i = 0; i &lt; prompts.length; ++i) { System.out.println("Enter the " + prompts[i] + " integer."); input.numbers[i] = keyboard.nextInt(); } System.out.println("The average of NUMBER1, NUMBER2, and NUMBER3 = " + input.average()); } } </code></pre> <p>Here I've added a constructor to <code>InputData</code> to initialize the array and given it an argument to set the size of the array.</p> <p>You could then introduce additional improvements like making the number of input values dynamic (using an <code>ArrayList&lt;Integer&gt;</code> instead of an <code>int</code> array). But this goes beyond the specific requirements of the assignment. Some people (many, actually) tend to do this kind of generalization automatically. However, advocates of <a href="http://en.wikipedia.org/wiki/Extreme_programming" rel="nofollow">Extreme Programming</a> will point out that it is generally better to keep things simple: design and code for the needs of today instead of those of tomorrow, next week, or next month.</p> <p>In other words, you don't know what the next assignment will bring, so however you generalize beyond the immediate assignment might be wasted work.</p>
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