Download the ZIP file from this URL and extract it to get the Jar. Add the Jar to your build path. To check the available classes in this Jar use this URL.

To Add this Jar to your build path Right click the Project > Build Path > Configure build path> Select Libraries tab > Click Add External Libraries > Select the Jar file Download

I hope this will solve your problem

• Right click on the Eclipse project,
• choose Properties
• Select Java Build Path
• Click the libraries tab
• click add external jars
• find the json jar(s) and add them.

I got it to work with the following:

public static void main(String[] args) throws IOException, ParseException{
    FileReader reader = new FileReader(new File("filename.json"));


    JSONParser jsonParser = new JSONParser();
    JSONArray jsonArray = (JSONArray) jsonParser.parse(reader);
    JSONObject object = (JSONObject) jsonArray.get(0);
    long elementaryProductId = (Long) object.get("elementaryProductId");



    System.out.println("The id is: " + elementaryProductId);
}

Explanation of the above:

You know the outermost element is an array so parse straight into a JSONArray. Next you want to pull out the first element of that array which is a JSONObject (its in braces). After that the code should be fairly self explanatory :)

import org.json.simple.JSONArray;

If using Maven, add this dependency to your pom.xml

<dependency>
    <groupId>javax.json</groupId>
    <artifactId>javax.json-api</artifactId>
    <version>1.0</version>
</dependency>

For Gradle, add this to your build.gradle

compile 'javax.json:javax.json-api:1.0'

You need to use the fully-qualified class name, which includes the package:

import org.json.JSONArray;

(And yes, that is the correct way to add classes/jars to your project's classpath in Eclipse.)

In Eclipse , navigate to

Windows ->Preferences -> Java -> Build Path -> ClassPath Variables

If your classpath variable 'JSON_JARS' is not present there, add it there, alongwith its location.

This should resolve your 'unbound classpath variable' error, if you have this error.

Moreover, put your execution codes in some method, or at least in main. For example :

package test;

import org.json.simple.*;

public class JSONTest {

    public void testMethod(){
        JSONObject obj = new JSONObject();
        obj.put("name","test");

        JSONArray list = new JSONArray();
        list.add("1234");
    }

    public static void main(String [] args){
        JSONObject obj = new JSONObject();
        obj.put("name","test");

        JSONArray list = new JSONArray();
        list.add("1234");
    }
}

This doesn't throw any error.

For the code which you have attached, if I am correct, there is no way for the code to populate the object and list, to get executed. This is why you get those errors.