Class NumberRange

src/main/java/groovy/lang/NumberRange.java:56–777

Represents an immutable list of Numbers from a value to a value with a particular step size. In general, it isn't recommended using a NumberRange as a key to a map. The range 0..3 is deemed to be equal to 0.0..3.0 but they have different hashCode values, so storing a value using one of these ranges

 * @since 2.5.0
 */
public class NumberRange extends AbstractList<Comparable> implements Range<Comparable>, Serializable {

    /**
     * The first value in the range.
     */
    @Serial private static final long serialVersionUID = 5107424833653948484L;
    private final Comparable from;

    /**
     * The last value in the range.
     */
    private final Comparable to;

    /**
     * The step size in the range.
     */
    private final Number stepSize;

    /**
     * The cached size, or -1 if not yet computed
     */
    private int size = -1;

    /**
     * The cached hashCode (once calculated)
     */
    private Integer hashCodeCache = null;

    /**
     * <code>true</code> if the range counts backwards from <code>to</code> to <code>from</code>.
     */
    private final boolean reverse;

    /**
     * <code>true</code> if the range includes the lower bound.
     */
    private final boolean inclusiveLeft;

    /**
     * <code>true</code> if the range includes the upper bound.
     */
    private final boolean inclusiveRight;

    /**
     * Creates an inclusive {@link NumberRange} with step size 1.
     * Creates a reversed range if <code>from</code> &lt; <code>to</code>.
     *
     * @param from the first value in the range
     * @param to   the last value in the range
     */
    public <T extends Number & Comparable, U extends Number & Comparable>
    NumberRange(T from, U to) {
        this(from, to, null, true, true);
    }

    /**
     * Creates a new {@link NumberRange} with step size 1.
     * Creates a reversed range if <code>from</code> &lt; <code>to</code>.