JSON对象转为Java类对象

本文讲述两种方法，使JSON对象转为Java类对象。基于FastJson1

对于以下的JSON对象：

{
    "message": "成功",
    "code": 1,
    "records": [
        {
            "id": 99309,
            "brokerName": "",
            "fileType": "协议",
            "effectiveDate": "20220818",
            "createDate": "20220812"
        },
        {
            "id": 99308,
            "brokerName": "",
            "fileType": "合同",
            "effectiveDate": "20220812",
            "createDate": "20220812"
        }
    ]
}

假设以上的JSON对象已通过toJSONString()方法转为String，那么有两种方法可以将其转为Java类对象，前提是已定义一个YourClass类，其成员变量可以容纳以上records内的各个字段，两种转换方法如下：

// 方法一：
JSONObject jsonResult = JSON.parseObject(result);	// result是以上JSON对象转成的String
String code = jsonResult.getString("code");
String message = jsonResult.getString("message");
JSONArray arrayData = jsonResult.getJSONArray("records");

for (Object obj : arrayData) {
    JSONObject jsonObj = (JSONObject) obj;
    YourClass agreement = JSON.toJavaObject(jsonObj, YourClass.class);
    agreement.setFilePath(concatYourClassPath(agreement.getId()));
    logger.info("单个对象:" + agreement.toString());
}


// 方法二：
JSONObject jsonResult = JSON.parseObject(result);
String code = jsonResult.getString("code");
String message = jsonResult.getString("message");
JSONArray jsonArray = jsonResult.getJSONArray("records");
List list = jsonArray.toJavaList(YourClass.class);
for (YourClass elem : list) {
    logger.info("单个对象:" + elem.toString());
}