Question

import java.io.FileWriter;
import java.io.IOException;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;

public class writejson {
    //public static void writejs(String attachmentValue)
    public static void main(String[] args) {
        String attachmentValue= "1234";
        {
            JSONObject obj = new JSONObject();
            obj.put("Attachement Id: ", attachmentValue);
            try (FileWriter file = new FileWriter("C:\\failedtestdata.json"))
            {
                file.write(obj.toJSONString());
                file.flush();
            }
            catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

在JSON文件中，不与现有记录重叠。如何在下一行创建新记录

Answer 1

1.Use Append true构造函数-类似于FileWriter（“ C：\ failedtestdata.json”，true） 2.在每次写入中添加\ n，因此默认情况下，追加将在下一行开始

Answer 2

import java.io.FileWriter;
import java.io.IOException;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;

public class WriteJson {

    public static void main(String[] args) {
        String attachmentValue= "1234";
        JSONObject obj = new JSONObject();
        obj.put("Attachement Id: ", attachmentValue);
        String loc="C:\\failedtestdata.json";
        try (FileWriter file = new FileWriter(loc,true))
        {
         //File Writer creates a file in write mode at the given location 
         file.write(obj.toJSONString());
         file.write(",");
         file.append("\n");
         file.flush();
        }
        catch (IOException e) {
            e.printStackTrace();
        }
    }
}

如何在不重叠先前数据的情况下编写JSON文件

2 个答案: