fastjson java 字段排序_fastjson toJSONString() 属性排序

最近使用fastjson序列化对象时，发现输出的json字符串中是按属性进行了排序。

public class Person {

private String name;

private Integer age;

private String gender;

private Double height;

private Double weight;

//省略get,set方法

}

public class FastJsonTest {

public static void main(String[] args) {

Person person = new Person();

person.setName("Tom");

person.setAge(20);

person.setGender("Male");

person.setHeight(180.5);

person.setWeight(80.5);

System.out.println(JSON.toJSONString(person));

}

}

输出：

{"age":20,"gender":"Male","height":180.5,"name":"Tom","weight":80.5}

通过@JSONType,@JSONField注解可以定义属性的顺序

@JSONType(orders={"name","age","gender","height","weight"})

public class Person {

private String name;

private Integer age;

private String gender;

private Double height;

private Double weight;

}

或者

public class Person {

@JSONField(ordinal = 1)

private String name;

@JSONField(ordinal = 2)

private Integer age;

@JSONField(ordinal = 3)

private String gender;

@JSONField(ordinal = 4)

private Double height;

@JSONField(ordinal = 5)

private Double weight;

}

输出：

{"name":"Tom","age":20,"gender":"Male","height":180.5,"weight":80.5}

如果每个VO都显示的指定顺序会比较繁琐。所以，我的问题是：

1、fastjson设计为按顺序输出的目的是什么？

2、有没有全局的配置，来取消属性排序的功能？