如何在java中将json数据转换为字符串
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How to convert a json data to string in java
提问by ss3419670
I want to convert json data to string
我想将json数据转换为字符串
import java.io.BufferedReader;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import org.json.JSONArray;
import org.json.JSONObject;
public static void main(String[] args) throws Exception
{
URL url = new URL("http://192.168.1.13/test/ProductWb.php?productId=9");
HttpURLConnection conn ;
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setReadTimeout(60);
conn.setRequestProperty("Accept", "application/json");
String json="";
json = readUrl(conn);
System.out.println(json);
JSONObject jsonObject=new JSONObject(json);
JSONArray jarray=jsonObject.getJSONArray("modeles");
JSONObject modele= jarray.getJSONObject("modele");
for (int i=0;i<modele.length();i++) {
System.out.println(modele(i).getString("id_product"));
System.out.println(modele(i).getString("meta_title"));
System.out.println("*********");
}
}
its show me the json data but give me this the error:
它向我展示了 json 数据，但给了我这个错误：
{"modeles":[{"modele":{"id_product":"9","id_shop":"1","id_lang":"4","description":null,"description_short":"<pre>Peugeot 208<\/pre>","info_prix":"","info_1":null,"info_2":null,"info_3":null,"info_4":null,"info_5":null,"link_rewrite":"208","meta_description":"Peugeot 208","meta_keywords":"peugeot 208","meta_title":"Peugeot 208","name":"208","available_now":"","available_later":""}}]}
Exception in thread "main" java.lang.IllegalStateException: This is not a JSON Array.
at com.google.gson.JsonElement.getAsJsonArray(JsonElement.java:106)
at com.autoreduc.services.TestProduct.main(TestProduct.java:59)
help me if you have any solution. thanks in advance
如果您有任何解决方案，请帮助我。提前致谢
采纳答案by codefreaK
In your code you read the json data from a URL. I just copied your data and pasted it in a file and read the file as your url was down. Here step by step I have shown how to parse your json object and content inside it. For this I used java-json-schema.jar.
在您的代码中，您从 URL 读取 json 数据。我只是复制了您的数据并将其粘贴到一个文件中，然后在您的 url 关闭时读取了该文件。在这里，我一步一步地展示了如何解析您的 json 对象和其中的内容。为此，我使用了java-json-schema.jar.
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Iterator;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;
public class Tets {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
JSONParser parser = new JSONParser();
try{
/* URL url = new URL("http://192.168.1.13/test/ProductWb.php?productId=9");
HttpURLConnection conn ;
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setReadTimeout(60);
conn.setRequestProperty("Accept", "application/json");*/
String json="";
Object obj = parser.parse(new FileReader("C:\XXX\XX\src\javapackage\t.json"));
JSONObject jsonObject = (JSONObject) obj;
System.out.println(jsonObject.toJSONString()); //modeles object
JSONArray name = (JSONArray) jsonObject.get("modeles");
System.out.println(name.toJSONString());//array inside modeles array
for (Object o : name)
{
JSONObject person = (JSONObject) o;
JSONObject person1 = (JSONObject)person.get("modele");
System.out.println(person.get("modele"));//modele object
System.out.println(person1.get("id_lang"));//modele attribute
}
}catch(Exception e){e.printStackTrace();}
}
}
OutPut
输出
Your Json Object
你的 Json 对象
{"modeles":[{"modele":{"id_lang":"4","info_5":null,"info_4":null,"link_rewrite":"208","meta_keywords":"peugeot 208","info_3":null,"info_2":null,"info_1":null,"available_now":"","meta_description":"Peugeot 208","id_product":"9","description_short":"<pre>Peugeot 208<\/pre>","description":null,"name":"208","info_prix":"","meta_title":"Peugeot 208","available_later":"","id_shop":"1"}}]}
Your Json Array contained in json Object
您包含在 json 对象中的 Json 数组
[{"modele":{"id_lang":"4","info_5":null,"info_4":null,"link_rewrite":"208","meta_keywords":"peugeot 208","info_3":null,"info_2":null,"info_1":null,"available_now":"","meta_description":"Peugeot 208","id_product":"9","description_short":"<pre>Peugeot 208<\/pre>","description":null,"name":"208","info_prix":"","meta_title":"Peugeot 208","available_later":"","id_shop":"1"}}]
Your Json Object inside array
你在数组中的 Json 对象
{"id_lang":"4","info_5":null,"info_4":null,"link_rewrite":"208","meta_keywords":"peugeot 208","info_3":null,"info_2":null,"info_1":null,"available_now":"","meta_description":"Peugeot 208","id_product":"9","description_short":"<pre>Peugeot 208<\/pre>","description":null,"name":"208","info_prix":"","meta_title":"Peugeot 208","available_later":"","id_shop":"1"}
Your Json Object id_lang atrribute value = 4
你的 Json 对象 id_lang 属性值 = 4
4
回答by Mena
Your JSON is not an array.
您的 JSON 不是数组。
It's a JSON object with one property: modeles, whose value is the array.
它是一个具有一个属性的 JSON 对象：modeles，其值为数组。
Parse the root as JsonObject.
将根解析为JsonObject.
回答by Nambi
{->represents JSONObject and
[->represents the JSONArray,
first get the jsonObject and then get the array in it.
{->代表JSONObject和
[->代表JSONArray，先获取jsonObject再获取其中的数组。
I tried with jsonObjectpackage import the jar
我尝试使用jsonObjectpackage import the jar
JSONObject jsonObject=new JSONObject(yourstring);
JSONArray jarray=jsonObject.getJSONArray("modeles");
JSONObject modele= jarray.getJSONObject("modele");
for (int i=0;i<modele.length();i++) {
System.out.println(modele(i).getString("id_product"));
System.out.println(modele(i).getString("meta_title"));
System.out.println("*********");
}
