JAVA comprehensive example

// OddEven.java
import javax.swing.JOptionPane;

public class OddEven {
    // "input" is the number that the user gives to the computer
    private int input; // a whole number("int" means integer)

    /*
     * This is the constructor method. It gets called when an object of the OddEven type
     * is being created.
     */
    public OddEven() {
    /*
     * In most Java programs constructors can initialize objects with default values, or create
     * other objects that this object might use to perform its functions. In some Java programs, the
     * constructor may simply be an empty function if nothing needs to be initialized prior to the
     * functioning of the object.  In this program's case, an empty constructor would suffice, even if
     * it is empty. A constructor must exist, however if the user doesn't put one in then the compiler
     * will create an empty one.
     */
    }

    // This is the main method. It gets called when this class is run through a Java interpreter.
    public static void main(String[] args) {
        /*
         * This line of code creates a new instance of this class called "number" (also known as an
         * Object) and initializes it by calling the constructor.  The next line of code calls
         * the "showDialog()" method, which brings up a prompt to ask you for a number
         */
        OddEven number = new OddEven();
        number.showDialog();
    }

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