### Question:
BigIntegerAccessor implements PropertyAccessor<BigInteger> { @Override public byte[] toBytes(Object object) { if (object == null) { return null; } BigInteger b = (BigInteger) object; return b.toByteArray(); }  @Override BigInteger fromBytes(Class targetClass, byte[] b); @Override byte[] toBytes(Object object); @Override String toString(Object object); @Override BigInteger fromString(Class targetClass, String s); @Override BigInteger getCopy(Object object); BigInteger getInstance(Class<?> clazz);  }### Answer:
@Test public void testToBytes() { Assert.assertNull(accessor.toString(null)); BigInteger v1 = new BigInteger("1111111111"); byte[] b = accessor.toBytes(v1); BigInteger v2 = accessor.fromBytes(BigInteger.class, b); Assert.assertEquals(v1, v2); }