java 使用ObjectMapper的方式实现Json和bean的转换

迷南。 2022-06-09 20:42 165阅读 0赞

第一、将json字符串转为bean

public class JsonToJavaBean {
        public static void main(String[] args) {
            String str="{\"student\":[{\"name\":\"leilei\",\"age\":23},{\"name\":\"leilei02\",\"age\":23}]}";
            Student stu = null;
            List list = null;
            try {
                ObjectMapper objectMapper=new ObjectMapper();
     StudentList studentList=objectMapper.readValue(str,StudentList.class);
                list=studentList.getStudent();
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
              } 
            for(Student s:list){
                System.out.println(s.getName()+" "+s.getAge());
            }
        }
    }

或者

@Controller
    public class OrderController extends BaseController { 
        @Autowired
        private ObjectMapper objectMapper1;
        @RequestMapping(value = "/order/searchOrderImportByItem")
        public ResponseData searchOrderImportByItem(@RequestParam("page") Integer page,
                @RequestParam("pagesize") Integer pagesize, HttpServletRequest request) {
            try {
                String formData = request.getParameter("formData");
                OrderQueryRequest orderQueryRequest = null;
                if (StringUtils.isNotBlank(formData)) {
                    objectMapper1.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm"));
                    orderQueryRequest = objectMapper1.readValue(formData, OrderQueryRequest.class);
                } else {
                    return null;
                }
                PageHelper.startPage(page, pagesize);
                List<OrderQueryRequest> list = orderService.searchOrderImportByItem(orderQueryRequest);
                return new ResponseData(list);
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }
    }

第二、将bean转为json

public static void main(String[] args) {
            ArrayList list=new ArrayList();
            Student s1=new Student();
            s1.setName("leilei");
            s1.setAge(23);
            Student s2=new Student();
            s2.setName("leilei02");
            s2.setAge(23);
            list.add(s1);
            list.add(s2);     
            StringWriter str=new StringWriter();      
            ObjectMapper objectMapper=new ObjectMapper();
            try {
                objectMapper.writeValue(str, list);
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }   
            System.out.println(str);
        }