java对象与json对象之间互相转换实现方法示例

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
public class MainClass {
  public static void main(String[] args) {
    TestJsonBean();
    TestJsonAttribute();
    TestJsonArray();
  }
  @SuppressWarnings("rawtypes")
  private static void TestJsonArray() {
    Student student1 = new Student();
    student1.setId(1);
    student1.setName("jag");
    student1.setSex("man");
    student1.setAge(25);
    student1.setHobby(new String[]{"篮球","游戏"});
    Student student2 = new Student();
    student2.setId(2);
    student2.setName("tom");
    student2.setSex("woman");
    student2.setAge(23);
    student2.setHobby(new String[]{"上网","跑步"});
    List<Student> list = new ArrayList<Student>();
    list.add(student1);
    list.add(student2);
    JSONArray jsonArray = JSONArray.fromObject(list);
    System.out.println(jsonArray.toString());
    JSONArray new_jsonArray=JSONArray.fromObject(jsonArray.toArray());
    Collection java_collection=JSONArray.toCollection(new_jsonArray);
    if(java_collection!=null && !java_collection.isEmpty())
    {
      Iterator it=java_collection.iterator();
      while(it.hasNext())
      {
        JSONObject jsonObj=JSONObject.fromObject(it.next());
        Student stu=(Student) JSONObject.toBean(jsonObj,Student.class);
        System.out.println(stu.getName());
      }
    }
  }
  private static void TestJsonAttribute() {
    /**
     * 创建json对象并为该对象设置属性
     */
    JSONObject jsonObj = new JSONObject();
    jsonObj.put("Int_att",25);//添加int型属性
    jsonObj.put("String_att","str");//添加string型属性
    jsonObj.put("Double_att",12.25);//添加double型属性
    jsonObj.put("Boolean_att",true);//添加boolean型属性
    //添加JSONObject型属性
    JSONObject jsonObjSon = new JSONObject();
    jsonObjSon.put("id",1);
    jsonObjSon.put("name","tom");
    jsonObj.put("JSONObject_att",jsonObjSon);
    //添加JSONArray型属性
    JSONArray jsonArray = new JSONArray();
    jsonArray.add("array0");
    jsonArray.add("array1");
    jsonArray.add("array2");
    jsonArray.add("array3");
    jsonObj.put("JSONArray_att",jsonArray);
    System.out.println(jsonObj.toString());
    System.out.println("Int_att:"+jsonObj.getInt("Int_att"));
    System.out.println("String_att:"+jsonObj.getString("String_att"));
    System.out.println("Double_att:"+jsonObj.getDouble("Double_att"));
    System.out.println("Boolean_att:"+jsonObj.getBoolean("Boolean_att"));
    System.out.println("JSONObject_att:"+jsonObj.getJSONObject("JSONObject_att"));
    System.out.println("JSONArray_att:"+jsonObj.getJSONArray("JSONArray_att"));
  }
  /**
   * java对象与json对象互相转换
   */
  private static void TestJsonBean() {
    /**
     * 创建java对象
     */
    Student student = new Student();
    student.setId(1);
    student.setName("jag");
    student.setSex("man");
    student.setAge(25);
    student.setHobby(new String[]{"篮球","上网","跑步","游戏"});
    /**
     * java对象转换成json对象，并获取json对象属性
     */
    JSONObject jsonStu = JSONObject.fromObject(student);
    System.out.println(jsonStu.toString());
    System.out.println(jsonStu.getJSONArray("hobby"));
    /**
     * json对象转换成java对象，并获取java对象属性
     */
    Student stu = (Student) JSONObject.toBean(jsonStu,Student.class);
    System.out.println(stu.getName());
    /**
     * 创建json对象
     */
    JSONObject jsonObj = new JSONObject();
    jsonObj.put("id",1);
    jsonObj.put("name","张勇");
    jsonObj.put("sex","男");
    jsonObj.put("age",24);
    //jsonObj.put("hobby",new String[]{"上网","游戏","音乐"});
    //System.out.println(jsonObj.toString());
    /**
     * json对象转换成java对象
     */
    Student stud = (Student) JSONObject.toBean(jsonObj,Student.class);
    System.out.println(stud.getName());
  }
}