JSON

jackson

import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.core.type.TypeReference;

https://gitee.com/vaq/magisk/raw/master/json/restTemplate.json

{
    "data": {
        "oneFissionReward": {
            "gold": null,
            "money": 10,
            "code": 0,
            "message": "success"
        },
        "twoFissionReward": {
            "gold": null,
            "money": 10,
            "code": 0,
            "message": "success"
        },
        "selfReward": {
            "code": 0,
            "message": "success",
            "coupons": [
                {
                    "couponCode": "123456",
                    "money": 10
                },
                {
                    "couponCode": "789789",
                    "money": 20
                }
            ]
        }
    },
    "code": 0,
    "message": "success"
}

ObjectMapper objectMapper = new ObjectMapper();
String resultString =objectMapper.writeValueAsString(obj);	//Object转String
JsonNode resultJson = objectMapper.readTree(str);	//String转JsonNode
JsonNode dataJson = resultJson.get("data");	//JsonNode获取下一子级JsonNode

if(null != dataJson){
	JsonNode selfRewardJson = dataJson.get(selfReward);
	if(null != selfRewardJson){
		String code = selfRewardJson.get("code").asText();
		String message = selfRewardJson.findValue("message").textValue();
		JsonNode couponsJson = selfRewardJson.findValue("coupons");
            if(null != couponsJson){
				List<CouponsDTO> coupons = objectMapper.readValue(couponsJson.toString(), new TypeReference<List<CouponsDTO>>(){});  //JsonNode转List,不能用couponsJson.asText(),因为这个参数必须要有双引号包裹
			}
	}
}

asText()、textValue()、toString()

String message = jsonNode.get("message").asText(); // success
String message1 = jsonNode.get("message").textValue(); // success String message2 = jsonNode.get("message").toString(); // "success"

System.out.println("success".equals(message)); true System.out.println("success".equals(message1)); true System.out.println("success".equals(message2)); false

toString会额外的前后再加上""

JsonNode

if(null != jsonNode) 判断是否存在该节点，oneFissionReward为true，gold也为true，vaq为false

修改JsonNode的结点值

要先转成ObjectNode
ObjectNode objectNode = (ObjectNode) dataJson;
objectNode.put("coupon",couponCount);

jsonNode.get()和.findValue()

? ?

String转List

1. 
import cn.hutool.json.JSONUtil;
List<PatientImgVo> list = JSONUtil.toList(JSONUtil.parseArray(jsonImgString), PatientImgVo.class);

2. 
import com.fasterxml.jackson.databind.ObjectMapper;
ObjectMapper objectMapper = new ObjectMapper();
List<PatientImgVo> imgUrlList = objectMapper.readValue(imgsUrlNode.toString(), new TypeReference<List<PatientImgVo>>(){});

List转String

import com.fasterxml.jackson.databind.ObjectMapper;
String s = objectMapper.valueToTree(list).toString();

获取数据后给对象赋值

Integer code = jsonNode.get("code").intValue(); code是Integer类型 Object data = jsonNode.get("data"); 获取的data是个JSON对象 String message = jsonNode.get("message").textValue(); message是String类型