Here is a simple Java tutorial which demonstrate how to parse JSONObject and JSONArrays in Java.
JSON syntax is a subset of the JavaScript object notation syntax:
- Data is in name/value pairs
- Data is separated by commas
- Curly braces hold objects
- Square brackets hold arrays
Just incase if you want to take a look at simple JSON tutorial which I’ve written sometime back. In this example we will read JSON File Crunchify_JSON.txt from file system and then we will iterate through it.
In order to run below Java project, please add below Maven Dependency to your project in pom.xml file.
<dependency> <groupId>org.json</groupId> <artifactId>json</artifactId> <version>20151123</version> </dependency>
Create this .txt file and update path in Java project:
{
"blogURL": "https://crunchify.com",
"twitter": "https://twitter.com/Crunchify",
"social": {
"facebook": "http://facebook.com/Crunchify",
"pinterest": "https://www.pinterest.com/Crunchify/crunchify-articles",
"rss": "https://crunchify.com/feed/"
}
}
Java Program:
package com.crunchify.tutorials;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import org.json.JSONException;
import org.json.JSONObject;
/**
* @author Crunchify.com
*
*/
public class CrunchifyParseJSONObject {
public static void main(String[] args) throws FileNotFoundException, JSONException {
String jsonData = "";
BufferedReader br = null;
try {
String line;
br = new BufferedReader(new FileReader("/Users/<username>/Documents/Crunchify_JSON.txt"));
while ((line = br.readLine()) != null) {
jsonData += line + "\n";
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (br != null)
br.close();
} catch (IOException ex) {
ex.printStackTrace();
}
}
// System.out.println("File Content: \n" + jsonData);
JSONObject obj = new JSONObject(jsonData);
System.out.println("blogURL: " + obj.getString("blogURL"));
System.out.println("twitter: " + obj.getString("twitter"));
System.out.println("social: " + obj.getJSONObject("social"));
}
}
Result:
blogURL: https://crunchify.com
twitter: https://twitter.com/Crunchify
social: {"facebook":"http://facebook.com/Crunchify","rss":"https://crunchify.com/feed/","pinterest":"https://www.pinterest.com/Crunchify/crunchify-articles"}