Java-JSON(Fastjson)

Fastjson 是常用的JSON库之一

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.78</version>
</dependency>

JAVA对象转换为JSON字符串

String text = JSON.toJSONString(obj);

更具体的示例

JSONObject obj = new JSONObject();

List<String> h1 = new ArrayList<String>();
h1.add("hello31");
h1.add("hello32");

HashMap<String, String> h2 = new HashMap<String, String>();
h2.put("a41", "hello411");
h2.put("a42", "hello421");

obj.put("a1", "hello1");
obj.put("a2", "hello2");
obj.put("a3", h1);
obj.put("a4", h2);

System.out.println(obj);
// {"a1":"hello1","a2":"hello2","a3":["hello31","hello32"],"a4":{"a42":"hello421","a41":"hello411"}}

JSON字符串转换为JAVA对象

VO vo = JSON.parseObject("{...}", VO.class);

更具体的示例

@Data
class VO {
    String a1;
    String a2;
    List<String> a3;
    HashMap<String, String> a4;
}

VO vo = JSON.parseObject("{\"a1\":\"hello1\",\"a2\":\"hello2\",\"a3\":[\"hello31\",\"hello32\"],\"a4\":{\"a42\":\"hello421\",\"a41\":\"hello411\"}}", VO.class);

System.out.println(vo);
// VO(a1=hello1, a2=hello2, a3=[hello31, hello32], a4={a42=hello421, a41=hello411})

@JSONField

设置JSON序列化和反序列化的Field名字

@Data
class VO {
    @JSONField(name="name")
    String a1;

    @JSONField(name="age")
    int a2;
}

VO vo = new VO();
vo.setA1("sin");
vo.setA2(30);

System.out.println(JSON.toJSONString(vo));
// {"age":30,"name":"sin"}

参考

• Fastjson 简明教程