Summary of conversion methods between entity classes and JSON objects

This time I will bring you a summary of the conversion methods between entity classes and JSONobjects, what are the notes for converting entity classes and JSON objects, the following is a practical case, let’s take a look one time.

When we need to use JSON objects to encapsulate data, we often write a lot of code and copy and paste. In order to use the idea of ​​POJO, we can convert JSON into entity objects for operation

package myUtil;
import java.io.IOException;
import myProject.Student;
import myProject.StudentList;
import org.codehaus.jackson.map.ObjectMapper;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
/**
 * 实体类和JSON对象之间相互转化（依赖包jackson-all-1.7.6.jar、jsoup-1.5.2.jar）
 * @author wck
 *
 */
public class JSONUtil {
  /**
   * 将json转化为实体POJO
   * @param jsonStr
   * @param obj
   * @return
   */
  public static<T> Object JSONToObj(String jsonStr,Class<T> obj) {
    T t = null;
    try {
      ObjectMapper objectMapper = new ObjectMapper();
      t = objectMapper.readValue(jsonStr,
          obj);
    } catch (Exception e) {
      e.printStackTrace();
    }
    return t;
  }
  /**
   * 将实体POJO转化为JSON
   * @param obj
   * @return
   * @throws JSONException
   * @throws IOException
   */
  public static<T> JSONObject objectToJson(T obj) throws JSONException, IOException {
    ObjectMapper mapper = new ObjectMapper(); 
    // Convert object to JSON string 
    String jsonStr = "";
    try {
       jsonStr = mapper.writeValueAsString(obj);
    } catch (IOException e) {
      throw e;
    }
    return new JSONObject(jsonStr);
  }
  public static void main(String[] args) throws JSONException, IOException {
    JSONObject obj = null;
    obj = new JSONObject();
    obj.put("name", "213");
    obj.put("age", 27);
    JSONArray array = new JSONArray();
    array.put(obj);
    obj = new JSONObject();
    obj.put("name", "214");
    obj.put("age", 28);
    array.put(obj);
    Student stu = (Student) JSONToObj(obj.toString(), Student.class);
    JSONObject objList = new JSONObject();
    objList.put("student", array);
    System.out.println("objList:"+objList);
    StudentList stuList = (StudentList) JSONToObj(objList.toString(), StudentList.class);
    System.out.println("student:"+stu);
    System.out.println("stuList:"+stuList);
    System.out.println("#####################################");
    JSONObject getObj = objectToJson(stu);
    System.out.println(getObj);
  }
}

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!

Recommended reading:

How to use Json.net

##How to convert objects into json format

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