return null;
        }
        final ParameterizedClassDesc pcd = parameterizedClassDesc.getArguments()[0];
        if (pcd == null) {
            return null;
        }
        return pcd.getRawClass();
    }

    @Override
    public Class<?> getKeyClassOfMap() {
        if (!Map.class.isAssignableFrom(propertyType) || !isParameterized()) {
            return null;
        }

        final Method m1 = ArrayType.class.getMethod("arrayOfStringClass");
        final Type t1 = m1.getGenericReturnType();
        final Type t2 = GenericsUtil.getElementTypeOfArray(t1);
        assertThat(GenericsUtil.getRawClass(t2), is(sameClass(Class.class)));
        assertThat(GenericsUtil.getGenericParameter(t2, 0), is(sameClass(String.class)));
    }

    /**
     * @throws Exception
     */

        assertThat(parameterizedClassDesc, is(notNullValue()));
        assertThat(parameterizedClassDesc.isParameterizedClass(), is(true));
        assertThat(parameterizedClassDesc.getRawClass(), is(sameClass(Class.class)));
        final MyBean myBean = new MyBean();
        aaa.setFieldValue(myBean, String.class);
        assertThat(aaa.getFieldValue(myBean), is(sameClass(String.class)));
    }

    /**