com.alibaba.fastjson使用總結

json的解析最主要的工作就是,javaBean對象,json對象,json格式字符串之間的相互轉換

參考博客:寫的比較全面,簡單易懂

https://segmentfault.com/a/1190000011212806

 

1. JSON格式字符串   ←→JSONObject對象

• JSON格式字符串 →JSONObject對象  

JSONObject jsonObject =JSONObject.parseObject((JSON_OBJ_STR);

JSONArray jsonArray =JSONArray.parseArray(JSON_ARRAY_STR);
    for (Object object : jsonArraystudents) {
        JSONObject jsonObjectone = (JSONObject) object;
    }

• JSONObject對象 →JSON格式字符串

    // 第一種方式
    String jsonString = JSONObject.toJSONString(jsonObject);

    // 第二種方式
    String jsonString = jsonObject.toJSONString();

 

     2. JSON格式字符串   ←→javaBean對象

 

• JSON格式字符串   →javaBean對

//第一種方式
    JSONObject jsonObject = JSONObject.parseObject(JSON_OBJ_STR);
    String studentName = jsonObject.getString("studentName");
    Integer studentAge = jsonObject.getInteger("studentAge");
    Student student = new Student(studentName, studentAge);

    List<Student> students = new ArrayList<Student>();
    Student student = null;
    for (Object object : jsonArray) {
        JSONObject jsonObjectone = (JSONObject) object;
        String studentName = jsonObjectone.getString("studentName");
        Integer studentAge = jsonObjectone.getInteger("studentAge");
        student = new Student(studentName,studentAge);
        students.add(student);
    }

//第二種方式,使用TypeReference<T>類,由於其構造方法使用protected進行修飾,故創建其子類
    Student student = JSONObject.parseObject(JSON_OBJ_STR, new TypeReference<Student>();

    List<Student> studentList = JSONArray.parseObject(JSON_ARRAY_STR, new TypeReference<ArrayList<Student>>() {});
   

//第三種方式,使用Gson的思想
    Student student = JSONObject.parseObject(JSON_OBJ_STR, Student.class);

    List<Student> studentList1 = JSONArray.parseArray(JSON_ARRAY_STR, Student.class);
    

•   javaBean對象 →JSON格式字符串

  String jsonString = JSONObject.toJSONString(student);
  
  List<Student> students = new ArrayList<Student>();
  String jsonString = JSONArray.toJSONString(students);

    3.JSONObject對象   ←→javaBean對象(以JSON字符串爲媒介)

• javaBean對象→JSONObject對象

      //方式一
      String jsonString = JSONObject.toJSONString(student);
      JSONObject jsonObject = JSONObject.parseObject(jsonString);
  
      String jsonString = JSONArray.toJSONString(students);
      JSONArray jsonArray = JSONArray.parseArray(jsonString);
  
  
      //方式二
      JSONObject jsonObject1 = (JSONObject) JSONObject.toJSON(student);
  
      JSONArray jsonArray1 = (JSONArray) JSONArray.toJSON(students);

• JSONObject→javaBean對象

      //第一種方式,使用TypeReference<T>類,由於其構造方法使用protected進行修飾,故創建其子類
      Student student = JSONObject.parseObject(jsonObject.toJSONString(), new TypeReference<Student>() {});
     
      ArrayList<Student> students = JSONArray.parseObject(jsonArray.toJSONString(),
              new TypeReference<ArrayList<Student>>() {});
  
  
      //第二種方式,使用Gson的思想
      Student student1 = JSONObject.parseObject(jsonObject.toJSONString(), Student.class);
     
      List<Student> students1 = JSONArray.parseArray(jsonArray.toJSONString(), Student.class);
  

 

另外還有以下兩個成員方法用的比較多:

JSONObject jsonObjectcourse = jsonObject.getJSONObject("course");

JSONArray jsonArraystudents = jsonObject.getJSONArray("students");

public void testComplexJSONStrToJSONObject() {

    JSONObject jsonObject = JSONObject.parseObject(COMPLEX_JSON_STR);

    String teacherName = jsonObject.getString("teacherName");
    Integer teacherAge = jsonObject.getInteger("teacherAge");

    System.out.println("teacherName:  " + teacherName + "   teacherAge:  " + teacherAge);

    JSONObject jsonObjectcourse = jsonObject.getJSONObject("course");
     //獲取JSONObject中的數據
    String courseName = jsonObjectcourse.getString("courseName");
    Integer code = jsonObjectcourse.getInteger("code");

    System.out.println("courseName:  " + courseName + "   code:  " + code);

    JSONArray jsonArraystudents = jsonObject.getJSONArray("students");

    //遍歷JSONArray
    for (Object object : jsonArraystudents) {

        JSONObject jsonObjectone = (JSONObject) object;
        String studentName = jsonObjectone.getString("studentName");
        Integer studentAge = jsonObjectone.getInteger("studentAge");

        System.out.println("studentName:  " + studentName + "   studentAge:  " + studentAge);
    }
}