package java.lang;

/**
 * The abstract class <code>Number</code> is the superclass of classes <code>BigDecimal</code>,
 * <code>BigInteger</code>, <code>Byte</code>, <code>Double</code>, <code>Float</code>,
 * <code>Integer</code>, <code>Long</code>, and <code>Short</code>.
 * <p>
 * Subclasses of <code>Number</code> must provide methods to convert the represented numeric value
 * to <code>byte</code>, <code>double</code>, <code>float</code>, <code>int</code>,
 * <code>long</code>, and <code>short</code>.
 *
 * @see java.lang.Byte
 * @see java.lang.Double
 * @see java.lang.Float
 * @see java.lang.Integer
 * @see java.lang.Long
 * @see java.lang.Short
 */
public abstract class Number implements java.io.Serializable {

    /**
     * Returns the value of the specified number as a <code>byte</code>. This may involve rounding or
     * truncation.
     *
     * @return the numeric value represented by this object after conversion to type <code>byte</code>.
     */
    public byte byteValue() {
        throw new RuntimeException();
    }

    /**
     * Returns the value of the specified number as a <code>double</code>. This may involve rounding.
     *
     * @return the numeric value represented by this object after conversion to type
     *         <code>double</code>.
     */
    public abstract double doubleValue();

    /**
     * Returns the value of the specified number as a <code>float</code>. This may involve rounding.
     *
     * @return the numeric value represented by this object after conversion to type <code>float</code>.
     */
    public abstract float floatValue();

    /**
     * Returns the value of the specified number as an <code>int</code>. This may involve rounding or
     * truncation.
     *
     * @return the numeric value represented by this object after conversion to type <code>int</code>.
     */
    public abstract int intValue();

    /**
     * Returns the value of the specified number as a <code>long</code>. This may involve rounding or
     * truncation.
     *
     * @return the numeric value represented by this object after conversion to type <code>long</code>.
     */
    public abstract long longValue();

    /**
     * Returns the value of the specified number as a <code>short</code>. This may involve rounding or
     * truncation.
     *
     * @return the numeric value represented by this object after conversion to type <code>short</code>.
     */
    public short shortValue() {
        throw new RuntimeException();
    }
}