Jackson转换泛型List出现错误java.util.LinkedHashMap cannot be cast to com.xxx

ObjectMapper mapper = new ObjectMapper();

List<ConsultantDto> list = new ArrayList<ConsultantDto>();

try {

list = mapper.readValue(con.getInputStream(), ArrayList.class);

} catch (JsonGenerationException e) {

e.printStackTrace();

} catch (JsonMappingException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

System.out.println(list.get(0));
System.out.println(list.get(0).getForename());
return list;

<span style="color:#FF0000;"><strong>java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to com.xxx.xxx.web.dto.rp.ConsultantDto</strong></span>

List<ConsultantDto> myObjects =
mapper.readValue(jsonInput, new TypeReference<List<ConsultantDto>>(){});