### Question:
IntegerAdapter extends XmlAdapter<String, Integer> { @Override public Integer unmarshal(String value){ return NumberUtil.parseInteger(value); }  @Override Integer unmarshal(String value); @Override String marshal(Integer value);  }### Answer:
@Test public void unmarshal(){ IntegerAdapter adapter = new IntegerAdapter(); assertEquals((Integer)(-1), adapter.unmarshal("-01")); assertEquals((Integer)(-1), adapter.unmarshal("-1")); assertEquals((Integer)0, adapter.unmarshal("-0")); assertEquals((Integer)0, adapter.unmarshal("0")); assertEquals((Integer)1, adapter.unmarshal("1")); assertEquals((Integer)1, adapter.unmarshal("01")); }