To know more about JSON , read “What is JSON and Understanding JSON syntax with simple example” and “Cloud Technologies”
In this post, we will show you how to write a simple JSON Array by writing code in JAVA. This post is related to our previous post “Example of creating simple JSON in JAVA”
$ vim simpleJsonArrayExample.java
import org.json.simple.JSONObject;
import org.json.simple.JSONArray;
public class simpleJsonArrayExample {
public static void main(String args[]) {
JSONObject myObject = new JSONObject();
myObject.put("myname", "lynxbee");
myObject.put("myurl", "www.lynxbee.com");
JSONArray myArray = new JSONArray();
JSONObject firstObjectInsideArray = new JSONObject();
firstObjectInsideArray.put("cms", "wordpress");
myArray.add(firstObjectInsideArray);
JSONObject secondObjectInsideArray = new JSONObject();
secondObjectInsideArray.put("platform", "linux");
myArray.add(secondObjectInsideArray);
myObject.put("technology", myArray);
System.out.println("We created JSON Array as example : " + myObject);
}
}
Lets try to understand few things, the JSON array has been created by using following code,
JSONArray myArray = new JSONArray();
and JSON objects which we add to array are created using following code,
JSONObject firstObjectInsideArray = new JSONObject();
firstObjectInsideArray.put("cms", "wordpress");
JSONObject secondObjectInsideArray = new JSONObject();
secondObjectInsideArray.put("platform", "linux");
Here, we tried to created two JSON objects which we will add to array as,
myArray.add(firstObjectInsideArray);
myArray.add(secondObjectInsideArray);
Now, Compile this program using javac compiler in Ubuntu as,
$ javac simpleJsonArrayExample.java
Error we received when tried to compile this program on Ubuntu,
javac simpleJsonArrayExample.java
simpleJsonArrayExample.java:1: error: package org.json.simple does not exist
import org.json.simple.JSONObject;
this error means, there is no JSON package is installed on your Ubuntu machine, so lets try and resolve this error…
$ sudo apt-get install libjson-simple-java
you can see this JSON library is installed as,
$ ls -alh /usr/share/java/json*
/usr/share/java/json-simple-2.3.0.jar -> json-simple.jar
/usr/share/java/json-simple.jar
Now we need to add this library to classpath as,
$ export CLASSPATH=$CLASSPATH:/usr/share/java/json-simple.jar
$ echo $CLASSPATH
:/usr/share/java/json-simple.jar
Now, lets again compile this program as,
$ javac simpleJsonArrayExample.java
Now, if we run the compiled JAVA program, we can see that we created simple JSON with only one object as below,
$ java simpleJsonArrayExample
We created JSON Array as example : {"myname":"lynxbee","myurl":"www.lynxbee.com","technology":[{"cms":"wordpress"},{"platform":"linux"}]}
As you can see, when we properly lint the JSON we can clearly see we are able to create an array of JSON objects i.e. “technology” is an array of objects…
{
"myname": "lynxbee",
"myurl": "www.lynxbee.com",
"technology": [{
"cms": "wordpress"
}, {
"platform": "linux"
}]
}