### Question:
MutableByte extends AbstractMutableInteger <MutableByte> { public MutableByte (final int nValue) { this ((byte) nValue); } MutableByte(final int nValue);  MutableByte(@Nonnull final Number aValue);  MutableByte(final byte nValue); @Override byte byteValue(); @Override float floatValue(); @Override double doubleValue(); @Override int intValue(); @Override long longValue(); int inc(); int inc(final int nDelta); int inc(@Nonnull final Number aDelta); int dec(); int dec(final int nDelta); int dec(@Nonnull final Number aDelta); @Nonnull EChange set(final int nValue); @Nonnull EChange set(final byte nValue); @Nonnull EChange set(@Nonnull final Number aValue); boolean is0(); boolean isLT0(); boolean isLE0(); boolean isGT0(); boolean isGE0(); boolean isEven(); int compareTo(@Nonnull final MutableByte rhs); @Nonnull MutableByte getClone(); @Override boolean equals(final Object o); @Override int hashCode(); @Override String toString();  }### Answer:
@Test public void testMutableByte () { final MutableByte x = new MutableByte (0); assertEquals (0, x.byteValue ()); assertEquals (Byte.valueOf ((byte) 0), x.getAsByte ()); assertFalse (x.isNot0 ()); assertTrue (x.is0 ()); x.inc (); assertEquals (1, x.byteValue ()); assertNotEquals (x.hashCode (), x.byteValue ()); x.inc (5); assertEquals (6, x.byteValue ()); assertNotEquals (x.hashCode (), x.byteValue ()); x.inc (-2); assertEquals (4, x.byteValue ()); assertNotEquals (x.hashCode (), x.byteValue ()); x.dec (); assertEquals (3, x.byteValue ()); assertFalse (x.isEven ()); assertNotEquals (x.hashCode (), x.byteValue ()); x.dec (5); assertEquals (-2, x.byteValue ()); assertTrue (x.isNot0 ()); assertFalse (x.is0 ()); assertTrue (x.isEven ()); assertNotEquals (x.hashCode (), x.byteValue ()); assertTrue (x.set (255).isChanged ()); assertFalse (x.set (255).isChanged ()); assertFalse (x.isEven ()); assertEquals (-1, x.byteValue ()); assertTrue (x.set (0).isChanged ()); assertEquals (0, x.byteValue ()); assertTrue (x.set (127).isChanged ()); assertEquals (127, x.byteValue ()); assertTrue (x.set (128).isChanged ()); assertEquals (-128, x.byteValue ()); assertTrue (x.set (255).isChanged ()); assertEquals (-1, x.byteValue ()); assertTrue (x.set (256).isChanged ()); assertEquals (0, x.byteValue ()); assertTrue (x.set (257).isChanged ()); assertEquals (1, x.byteValue ()); assertEquals (-1, new MutableByte (4).compareTo (new MutableByte (5))); assertEquals (0, new MutableByte (5).compareTo (new MutableByte (5))); assertEquals (+1, new MutableByte (6).compareTo (new MutableByte (5))); assertNotNull (x.toString ()); assertTrue (x.toString ().contains (Integer.toString (x.byteValue ()))); x.set (-1); assertFalse (x.isGT0 ()); x.set (0); assertFalse (x.isGT0 ()); x.set (1); assertTrue (x.isGT0 ()); CommonsTestHelper.testDefaultImplementationWithEqualContentObject (new MutableByte (-7), new MutableByte (-7)); CommonsTestHelper.testDefaultImplementationWithDifferentContentObject (new MutableByte (6), new MutableByte (7)); CommonsTestHelper.testGetClone (new MutableByte (Integer.MAX_VALUE)); }