JAVA的驼峰和下划线互转帮助类

实体类：

 import java.io.Serializable;
 import lombok.AllArgsConstructor;
 import lombok.Data;
 import lombok.NoArgsConstructor;

 @Data
 @AllArgsConstructor
 @NoArgsConstructor
 public class User implements Serializable {
     /**
      *
      */
     private static final long serialVersionUID = -329066647199569031L;

     private String userName;

     private String orderNo;
 }

帮助类：

 import java.io.IOException;

 import com.fasterxml.jackson.annotation.JsonInclude.Include;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.PropertyNamingStrategy;

 /**
  * JSON的驼峰和下划线互转帮助类
  *
  * @author yangzhilong
  *
  */
 public class JsonUtils {

     /**
      * 将对象的大写转换为下划线加小写，例如：userName-->user_name
      *
      * @param object
      * @return
      * @throws JsonProcessingException
      */
     public static String toUnderlineJSONString(Object object) throws JsonProcessingException{
         ObjectMapper mapper = new ObjectMapper();
         mapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);
         mapper.setSerializationInclusion(Include.NON_NULL);
         String reqJson = mapper.writeValueAsString(object);
         return reqJson;
     }

     /**
      * 将下划线转换为驼峰的形式，例如：user_name-->userName
      *
      * @param json
      * @param clazz
      * @return
      * @throws IOException
      */
     public static <T> T toSnakeObject(String json, Class<T> clazz) throws IOException{
         ObjectMapper mapper = new ObjectMapper();
　　        // mapper的configure方法可以设置多种配置（例如：多字段 少字段的处理）
　　　　　　 //mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
         mapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);
         T reqJson =  mapper.readValue(json, clazz);
         return reqJson;
     }
 }

单元测试类：

 import java.io.IOException;

 import org.junit.Test;

 import com.alibaba.fastjson.JSONObject;
 import com.fasterxml.jackson.core.JsonProcessingException;

 public class JsonTest {

     @Test
     public void testToUnderlineJSONString(){
         User user = new User("张三", "1111111");
         try {
             String json = JsonUtils.toUnderlineJSONString(user);
             System.out.println(json);
         } catch (JsonProcessingException e) {
             e.printStackTrace();
         }
     }

     @Test
     public void testToSnakeObject(){
         String json = "{\"user_name\":\"张三\",\"order_no\":\"1111111\"}";
         try {
             User user = JsonUtils.toSnakeObject(json, User.class);
             System.out.println(JSONObject.toJSONString(user));
         } catch (IOException e) {
             e.printStackTrace();
         }
     }
 }

测试结果：

 {"user_name":"张三","order_no":"1111111"}

 {"orderNo":"1111111","userName":"张三"}