jackson将JSON字符串转换成复杂的数据类型

﹏ヽ暗。殇╰゛Y 2023-08-17 16:18 138阅读 0赞

private static ObjectMapper objectMapper = new ObjectMapper();
       /**
         * 示例1：
         *         List<Map<Integer, String>> list = Lists.newArrayList();
         *         Map<Integer, String> map = Maps.newHashMap();
         *         map.put(12, "gg");
         *         map.put(34, "sd");
         *         list.add(map);
         *         List<Map<Integer, String>> list1 = toJavaBean(JSONUtils.toJSONString(list), ArrayList.class, HashMap.class);
         * 示例2：
         *         Map<Integer, String> map = Maps.newHashMap();
         *         map.put(12, "gg");
         *         map.put(34, "sd");
         *         Map<Integer, String> map1 = toJavaBean(JSONUtils.toJSONString(map), HashMap.class, Integer.class, String.class);
         * @param jsonString JSON字符串
         * @param parametrized 数据类型最外层class或者泛型实际的class, 如List<Map<String, Integer>>的List.class 或者Map<String, Integer>中的Map.class
         * @param parameterClasses 参数内部类型，如List<Map<String, Object>中的Map.class 或者Map<String, Integer>中的String.class、Integer.class
         * @param <T>
         * @return
         */
        public static <T> T toJavaBean(String jsonString, Class<?> parametrized, Class<?>... parameterClasses){
            try{
                JavaType javaType = javaType(parametrized, parameterClasses);
                return objectMapper.readValue(jsonString, javaType);
            } catch (JsonParseException e){
                e.printStackTrace();
                LoggerUtil.error(JSONUtils.class, e.toString());
            } catch (JsonMappingException e){
                e.printStackTrace();
                LoggerUtil.error(JSONUtils.class, e.toString());
            } catch (IOException e){
                e.printStackTrace();
                LoggerUtil.error(JSONUtils.class, e.toString());
            }
            return null;
        }
        /**
         *  示例1：
         *  Map<Integer, String> map = Maps.newHashMap();
         *  JavaType javaType = javaType(Map.class, Integer.class, String.class);
         *  示例2：
         *   List<Map<Integer, String>> list = Lists.newArrayList();
         *   Map<Integer, String> map = Maps.newHashMap();
         *   map.put(12, "gg");
         *   map.put(34, "sd");
         *   list.add(map);
         *   JavaType javaType = javaType(List.class, Map.class);
         * @param parametrized 实际的数据类型，即最外层数据类型List
         * @param parameterClasses 内部参数类型，即Set.class Bean.class
         * @return
         */
        public static JavaType javaType(Class<?> parametrized, Class<?>... parameterClasses){
            return objectMapper.getTypeFactory().constructParametricType(parametrized, parameterClasses);
        }

上面只列出了工具包的部分代码，其它的可以参考我的源码；  
GitHub源码地址：[https://github.com/mingyang66/spring-parent/blob/master/sgrain-spring-boot-common/doc/JSON%E5%B7%A5%E5%85%B7%E7%B1%BB.md][https_github.com_mingyang66_spring-parent_blob_master_sgrain-spring-boot-common_doc_JSON_E5_B7_A5_E5_85_B7_E7_B1_BB.md]

[https_github.com_mingyang66_spring-parent_blob_master_sgrain-spring-boot-common_doc_JSON_E5_B7_A5_E5_85_B7_E7_B1_BB.md]: https://github.com/mingyang66/spring-parent/blob/master/sgrain-spring-boot-common/doc/JSON%E5%B7%A5%E5%85%B7%E7%B1%BB.md