com.alibaba.fastjson.JSONObject之对象与JSON转换方法（转）

https://www.cnblogs.com/ibigboy/p/11124524.html#_label0

com.alibaba.fastjson.JSONObject时经常会用到它的转换方法，包括Java对象转成JSON串、JSON对象，JSON串转成java对象、JSON对象，JSON对象转换Java对象、JSON串等，使用方法总结如下

1、Java对象-->JSON对象

(JSONObject)JSONObject.toJSON(Java对象实例)

public class JSON2JavaTest{
    public static void main(String[] args) {
        Student stu = new Student("公众号编程大道", "m", 2);

        //Java对象转化为JSON对象
        JSONObject jsonObject = (JSONObject) JSONObject.toJSON(stu);
        System.out.println("Java对象转化为JSON对象
" + jsonObject);//{"name":"公众号编程大道","age":2,"sex":"m"}

    }
}

2、Java对象-->JSON字符串

JSONObject.toJSONString(Java对象实例)

public class JSON2JavaTest{
    public static void main(String[] args) {
        Student stu = new Student("公众号编程大道", "m", 2);

        //Java对象转换成JSON字符串
        String stuString = JSONObject.toJSONString(stu);
        System.out.println("Java对象转换成JSON字符串
" + stuString);//{"age":2,"name":"公众号编程大道","sex":"m"}
    }
}

3、JSON对象-->JSON字符串

JSONObject.toJSONString();

public class JSON2JavaTest{
    public static void main(String[] args) {
        Student stu = new Student("公众号编程大道", "m", 2);

        //先转成JSON对象
        JSONObject jsonObject = (JSONObject) JSONObject.toJSON(stu);

        //JSON对象转换为JSON字符串
        String jsonString = jsonObject.toJSONString();
        System.out.println("JSON对象转换为JSON字符串
" + jsonString);//{"name":"公众号编程大道","age":2,"sex":"m"}

    }
}

4、JSON对象-->Java对象

 JSONObject.toJavaObject(JSON对象实例, Java对象.class);

public class JSON2JavaTest{
    public static void main(String[] args) {
        Student stu = new Student("公众号编程大道", "m", 2);

        //先转成JSON对象
        JSONObject jsonObject = (JSONObject) JSONObject.toJSON(stu);
        
        //JSON对象转换成Java对象
        Student student = JSONObject.toJavaObject(jsonObject, Student.class);
        System.out.println("JSON对象转换成Java对象
" + student);//Student{name='公众号编程大道', sex='m', age=2}
    }
}

5、JSON字符串-->JSON对象

JSONObject.parseObject(JSON字符串)

public class JSON2JavaTest{
    public static void main(String[] args) {
        String stuString = "{"age":2,"name":"公众号编程大道","sex":"m"}";

        //JSON字符串转换成JSON对象
        JSONObject jsonObject1 = JSONObject.parseObject(stuString);
        System.out.println("JSON字符串转换成JSON对象
" + jsonObject1);//{"sex":"m","name":"公众号编程大道","age":2}
    }
}

6、JSON字符串-->Java对象

JSONObject.parseObject(JSON字符串, Java对象.class);

public class JSON2JavaTest{
    public static void main(String[] args) {
        String stuString = "{"age":2,"name":"公众号编程大道","sex":"m"}";

        //JSON字符串转换成Java对象
        Student student1 = JSONObject.parseObject(stuString, Student.class);
        System.out.println("JSON字符串转换成Java对象
" + student1);//Student{name='公众号编程大道', sex='m', age=2}
    }
}

---