JSON 解析工具的封装(Java)

JSON 解析工具的封装（Java）

　　一直想有一个属于自己的JSON工具，今天终于弄好了.....

　　　1.添加pom依赖包

• <!--json解析-->
          <dependency>
              <groupId>com.fasterxml.jackson.core</groupId>
              <artifactId>jackson-core</artifactId>
              <version>2.7.4</version>
          </dependency>
          <dependency>
              <groupId>com.fasterxml.jackson.core</groupId>
              <artifactId>jackson-databind</artifactId>
              <version>2.7.4</version>
          </dependency>

　　2.JSONUtils.java

1. import com.fasterxml.jackson.annotation.JsonInclude;
   import com.fasterxml.jackson.core.type.TypeReference;
   import com.fasterxml.jackson.databind.DeserializationFeature;
   import com.fasterxml.jackson.databind.ObjectMapper;
   import com.fasterxml.jackson.databind.SerializationFeature;
   
   import java.io.IOException;
   import java.text.SimpleDateFormat;
   import java.util.*;
   
   /**
    * Created by 杨永生 on 2017/4/26.
    */
   public class JSONUtils {
   
       private final static ObjectMapper objectMapper = new ObjectMapper();
   
       static {
           //去掉默认的时间戳格式
           objectMapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);
           //设置为中国上海时区
           objectMapper.setTimeZone(TimeZone.getTimeZone("GMT+8"));
           objectMapper.configure(SerializationFeature.WRITE_NULL_MAP_VALUES, false);
           //空值不序列化
           objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
           //反序列化时，属性不存在的兼容处理
           objectMapper.getDeserializationConfig().withoutFeatures(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
           //序列化时，日期的统一格式
           objectMapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
   
           objectMapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
           objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
           //单引号处理
           objectMapper.configure(com.fasterxml.jackson.core.JsonParser.Feature.ALLOW_SINGLE_QUOTES, true);
       }
   
       private JSONUtils() {
   
       }
   
       public static ObjectMapper getInstance() {
   
           return objectMapper;
       }
   
       /**
        * javaBean,list,array convert to json string
        */
       public static String obj2json(Object obj){
           try {
               return objectMapper.writeValueAsString(obj);
           }catch (Exception e){
               e.printStackTrace();
           }
           return "";
       }
   
       public static <T> T obj2obj(Object obj, Class<T> clazz){
           try {
              String str=obj2json(obj);
               return json2pojo(str,clazz);
           }catch (Exception e){
               e.printStackTrace();
           }
           return null;
       }
   
       /**
        * json string convert to javaBean
        */
       public static <T> T json2pojo(String jsonStr, Class<T> clazz) {
           try {
               return objectMapper.readValue(jsonStr, clazz);
           }catch (Exception e){
               e.printStackTrace();
           }
           return null;
       }
   
       /**
        * json string convert to map
        */
       public static <T> Map<String, Object> json2map(String jsonStr)
               throws Exception {
           return objectMapper.readValue(jsonStr, Map.class);
       }
   
       public static <T> T fromJson(TypeReference<T> tr,byte[] content){
           T t=null;
           try {
               t = objectMapper.readValue(content,0, content.length, tr);
           } catch (IOException e) {
               e.printStackTrace();
           }
           return t;
       }
   
       /**
        * json string convert to map with javaBean
        */
       public static <T> Map<String, T> json2map(String jsonStr, Class<T> clazz)
               throws Exception {
           Map<String, Map<String, Object>> map = objectMapper.readValue(jsonStr,
                   new TypeReference<Map<String, T>>() {
                   });
           Map<String, T> result = new HashMap<String, T>();
           for (Map.Entry<String, Map<String, Object>> entry : map.entrySet()) {
               result.put(entry.getKey(), map2pojo(entry.getValue(), clazz));
           }
           return result;
       }
   
       /**
        * json array string convert to list with javaBean
        */
       public static <T> List<T> json2list(String jsonArrayStr, Class<T> clazz)
               throws Exception {
           List<Map<String, Object>> list = objectMapper.readValue(jsonArrayStr,
                   new TypeReference<List<T>>() {
                   });
           List<T> result = new ArrayList<T>();
           for (Map<String, Object> map : list) {
               result.add(map2pojo(map, clazz));
           }
           return result;
       }
   
       /**
        * map convert to javaBean
        */
       public static <T> T map2pojo(Map map, Class<T> clazz) {
           return objectMapper.convertValue(map, clazz);
       }
   }

   3.示例:

　　　　　　Article article=JSONUtils.json2pojo(tempString, Article.class);