Can I make a Java Number subclass automatically box and unbox?

I am creating some classes to represent Unsigned numbers for Java and deriving them from Number. One of my goals is to make them box and unbox primitive values but I can't get this to work nor find any discussion of how to achieve this elsewhere. Can this be done and if so how? Here is my not working code! ``` public class Unsigned8 extends Number implements Comparable<Unsigned8>{ public static final long MAX_VALUE = 256L; public static final long MIN_VALUE = 0; private long _Value; public Unsigned8(long value) { this._Value = value; } @Override public byte byteValue() { return (byte) _Value; } @Override public short shortValue() { return (short) _Value; } @Override public int intValue() { return (int) _Value; } @Override public long longValue() { return (long) _Value; } @Override public double doubleValue() { return _Value; } @Override public float floatValue() { return _Value; } @Override public int compareTo(Unsigned8 target) { return (int) (_Value - target._Value); } ``` }