我正在尝试使用 Java 解析 json 文件。下面给出了我的 json 文件格式。如果操作是“注释”,我试图打印一条消息并打印 Performed_at。但是,以下代码没有输出。
预先感谢您的建议和您的时间。非常感谢。
{
"data": {
"name": "John"
},
"activities_data": [{
"performed_at": "April",
"id": 630,
"action": {
"address": "N/A",
"issue_type": "F A"
}
},
{
"performed_at": "March",
"id": 687,
"action": {
"note": {
"id": 26519,
"type": 4
}
}
}
]
}
Java代码:
import java.io.FileReader;
import java.io.IOException;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;
import java.io.Reader;
import java.util.Iterator;
import java.util.Map;
public class Readjsonfile {
public static void main(String[] args) throws Exception {
JSONParser parser = new JSONParser();
JSONObject ticketObject = (JSONObject) parser.parse(new FileReader("activity.json"));
JSONArray jsonArray= (JSONArray) ticketObject.get("activities_data");
for(int i=0; i<jsonArray.size(); i++){
Map activityobject = ((Map)jsonArray.get(i));
System.out.println(activityobject);
if (activityobject.containsKey("note"))
{
System.out.println("its a note");
\\and print performed_at here
}
}
}
}
最佳答案
您应该嵌套更深的一层才能获得注释。
for(int i=0; i<jsonArray.size(); i++){
Map activityobject = ((Map)jsonArray.get(i));
System.out.println(activityobject);
if (activityobject.containsKey("action")) {
Map actionObject = ((Map)activityobject.get("action"));
if (actionObject.containsKey("note")) {
System.out.println("its a note");
System.out.println("note" + actionObject.get("note"));
System.out.println("Performed at " + activityobject.get("performed_at"));
}
}
}
输出
{"performed_at":"April","action":{"address":"N\/A","issue_type":"F A"},"id":630}
{"performed_at":"March","action":{"note":{"id":26519,"type":4}},"id":687}
its a note
note{"id":26519,"type":4}
Performed at March
关于java - 解析json数据时如何判断key是否存在,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/56090583/